Configuration keys

Configuration keys are entry point configurations that allow users and admins to dynamically fine-tune HAProxy status. HAProxy Ingress reads configuration keys from Kubernetes resources, and this can be done in a couple of ways:

• Globally, from a ConfigMap
• Per IngressClass, from a ConfigMap linked in the IngressClass’ parameters field
• Per Ingress, configuring or annotating Ingress resources
• Per backend, annotating Service resources

The list above also describes the precedence if the same configuration key is used in more than one resource: Global configurations can be overridden by IngressClass configurations, that can be overridden by Ingress resource configurations and so on. This hierarchy creates a flexible model, where commonly used configurations can be made in a higher level and overridden by local changes.

The following sections describe in a few more details how HAProxy Ingress classifies an Ingress to be part of the final configuration, and how it reads the configuration from Kubernetes resources.

Class matter

HAProxy Ingress by default does not listen to Ingress resources, until one or more of the following conditions are met:

• Ingress resources have the annotation kubernetes.io/ingress.class with the value haproxy
• Ingress resources have its ingressClassName field assigning an IngressClass resource whose controller name is haproxy-ingress.github.io/controller
• HAProxy Ingress was started with --watch-ingress-without-class command-line option

See Ingress Class command-line doc for customization options.

The first two options give more control on which Ingress resources should be part of the final configuration. Class annotation and the IngressClass name can be changed on a running controller, the configuration will be adjusted on the fly to reflect the new status. If both options are configured in an Ingress resource, and they conflict - i.e. one of them says the controller belongs to HAProxy Ingress and the other says that it does not belong - the annotation value wins and a warning is logged.

Adding a class annotation or defining an IngressClass name means “classify” an Ingress resource. The third and latest option asks HAProxy Ingress to also add “unclassified” Ingress to the final configuration - i.e. add Ingress resources that does not have the kubernetes.io/ingress.class annotation and also does not have the ingressClassName field. Note that this is a new behavior since v0.12. Up to v0.11 HAProxy Ingress listen to “unclassified” Ingress by default.

Strategies

HAProxy Ingress reads configuration on three distinct ways:

• ConfigMap key/value data. ConfigMaps are assigned either via --configmap command-line option (used by Global options), or via parameters field of an IngressClass
• Annotations from classified Ingress resources and also from Services that these Ingress are linking to
• Spec configurations from classified Ingress resources

HAProxy Ingress follows Ingress v1 spec, so any Ingress spec configuration should work as stated by the Kubernetes documentation.

Annotations and ConfigMap customizations extend the Ingress spec via the configuration keys, and this is what the rest of this documentation page is all about.

The following sections describe in a few more details about configuration strategies.

ConfigMap

ConfigMap key/value options are read in the following conditions:

• Global config, using --configmap command-line option. The installation process configures a Global config ConfigMap named haproxy-ingress in the controller namespace. This is the only way to configure keys from the Global scope. See about scopes later in this page. Note, --configmap needs to be in the following format: <namespace>/<configmap-name>.
• IngressClass config, using its parameters field linked to a ConfigMap declared in the same namespace of the controller. See about IngressClass later in this same section.

A configuration key is used verbatim as the ConfigMap key name, without any prefix. The ConfigMap spec expects a string as the key value, so declare numbers and booleans as strings, HAProxy Ingress will convert them when needed.

apiVersion: v1
data:
  balance-algorithm: leastconn
  max-connections: "10000"
  ssl-redirect: "true"
kind: ConfigMap
metadata:
  name: haproxy-ingress
  namespace: ingress-controller

Annotation

Annotations are read in the following conditions:

• From classified Ingress resources, see about classification in the Class matter section. Ingresses accept keys from the Host, Backend, Path and TCP scopes. See about scopes later in this page.
• From Services that classified Ingress resources are linking to. Services only accept keys from the Backend scope.

A configuration key needs a prefix in front of its name to use as an annotation key. The default prefix is haproxy-ingress.github.io, and ingress.kubernetes.io is also supported for backward compatibility. Change the prefix with the --annotations-prefix command-line option. The annotation value spec expects a string as the key value, so declare numbers and booleans as strings, HAProxy Ingress will convert them when needed.

apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  annotations:
    haproxy-ingress.github.io/balance-algorithm: roundrobin
    haproxy-ingress.github.io/maxconn-server: "500"
    haproxy-ingress.github.io/ssl-redirect: "false"
  name: app
  namespace: default
spec:
  ...

IngressClass

IngressClass configurations are read when the ingressClassName field of an Ingress resource links to an IngressClass that configures its parameters field.

The IngressClass’ parameters field currently only accepts ConfigMap resources, and the ConfigMap must be declared in the same namespace of the controller.

The following resources create the same final configuration of the Annotation section above, with the benefit of allowing the reuse of the IngressClass+ConfigMap configuration.

apiVersion: networking.k8s.io/v1
kind: IngressClass
metadata:
  name: my-class
spec:
  controller: haproxy-ingress.github.io/controller
  parameters:
    kind: ConfigMap
    name: my-options

apiVersion: v1
data:
  balance-algorithm: roundrobin
  maxconn-server: "500"
  ssl-redirect: "false"
kind: ConfigMap
metadata:
  name: my-options
  namespace: ingress-controller

apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: app
  namespace: default
spec:
  ingressClassName: my-class
  ...

Updates

Changes to any configuration in any classified Ingress resources (annotations or spec), Service resources (annotations) or any referenced ConfigMap will reflect in the update of the final HAProxy configuration.

If the new state cannot be dynamically applied and requires HAProxy to be reloaded, this will happen preserving the in progress requests and the long running connections.

Fragmentation

Ingress resources can be fragmented in order to add distinct configurations to distinct routes. For example:

apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: app-front
spec:
  rules:
  - host: app.local
    http:
      paths:
      - path: /
        pathType: Prefix
        backend:
          service:
            name: frontend
            port:
              number: 8080

apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  annotations:
    haproxy-ingress.github.io/rewrite-target: /
  name: app-back
spec:
  rules:
  - host: app.local
    http:
      paths:
      - path: /api
        pathType: Prefix
        backend:
          service:
            name: backend
            port:
              number: 8080

HAProxy Ingress will merge all the resources, so there is no difference if the configuration is in the same or in distinct Ingress. Distinct Ingress however might lead to conflicting configuration, more about conflict in the scope section below.

There is no hard limit to the number of Ingresses or Services - clusters with tens of thousands of Ingress and Service resources report to work smoothly and fast with HAProxy Ingress.

Scope

HAProxy Ingress configuration keys may be in one of five distinct scopes: Global, Host, Backend, Path, TCP. A scope defines where a configuration key can be declared and how it interacts with Ingress and Service resources.

Configuration keys declared in Ingress resources might conflict. More about the scenarios in the Host, Backend and TCP scopes below. A warning will be logged in the case of a conflict, and the used value will be of the Ingress resource that was created first.

Global

Defines configuration keys that apply for all hostnames and backend services, and should be declared only in the Global config ConfigMap resource. Configuration keys of the Global scope declared as Ingress or Service annotations, and also in the IngressClass ConfigMap are ignored. Configuration keys of the Global scope never conflict.

Host

Defines configuration keys that bind to the hostname. Configuration keys of the host scope can be declared in any ConfigMap, or in any Ingress resource. A conflict happens when the same host configuration key with distinct values are declared in distinct Ingress resources but to the same hostname.

Backend

Defines configuration keys that bind to the Service resource, which is converted to a HAProxy backend after the configuration parsing. Configuration keys of the backend scope can be declared in any ConfigMap or as Ingress or Service annotation. A conflict happens when the same backend configuration key with distinct values are declared in distinct Ingress resources but to the same Service or HAProxy backend.

Path

Defines configuration keys that bind to the hostname and the HTTP path. Configuration keys of the Path scope can be declared in any ConfigMap as a default value, or as Ingress or Service annotation. Configuration keys of the Path scope never conflict.

TCP

Defines configuration keys that bind on the port number of a TCP service. Configuration keys of the TCP scope can be declared in any ConfigMap as a default value, or as Ingress annotation. A conflict happens when the same TCP configuration key with distinct values are declared in distinct Ingress resources but to the same TCP port number.

Keys

The table below describes all supported configuration keys.

Acme

Configures dynamic options used to authorize and sign certificates against a server which implements the acme protocol, version 2.

The popular Let’s Encrypt certificate authority implements acme-v2.

Supported acme configuration keys:

• acme-emails: mandatory, a comma-separated list of emails used to configure the client account. The account will be updated if this option is changed.
• acme-endpoint: mandatory, endpoint of the acme environment. v2-staging and v02-staging are alias to https://acme-staging-v02.api.letsencrypt.org, while v2 and v02 are alias to https://acme-v02.api.letsencrypt.org.
• acme-expiring: how many days before expiring a certificate should be considered old and should be updated. Defaults to 30 days.
• acme-preferred-chain: optional, defines the Issuer’s CN (Common Name) of the topmost certificate in the chain, if the acme server offers multiple certificate chains. The default certificate chain will be used if empty or no match is found. Note that changing this option will not force a new certificate to be issued if a valid one is already in place and actual and preferred chains differ. A new certificate can be emitted by changing the secret name in the ingress resource, or removing the secret being referenced.
• acme-shared: defines if another certificate signer is running in the cluster. If false, the default value, any request to /.well-known/acme-challenge/ is sent to the local acme server despite any ingress object configuration. Otherwise, if true, a configured ingress object would take precedence.
• acme-terms-agreed: mandatory, it should be defined as true, otherwise certificates won’t be issued.
• cert-signer: defines the certificate signer that should be used to authorize and sign new certificates. The only supported value is "acme". Add this config as an annotation in the ingress object that should have its certificate managed by haproxy-ingress and signed by the configured acme environment. The annotation kubernetes.io/tls-acme: "true" is also supported if the command-line option --acme-track-tls-annotation is used.

Minimum setup

The command-line option --acme-server need to be declared to start the local server and the work queue used to authorize and sign new certificates. See other command-line options here.

The following configuration keys are mandatory: acme-emails, acme-endpoint, acme-terms-agreed.

A cluster-wide permission to create and update the secrets resources should also be made.

How it works

All haproxy-ingress instances should declare --acme-server command-line option, which will start a local server to answer acme challenges, a work queue to enqueue the domain authorization and certificate signing, and will also start a leader election to define which haproxy-ingress instance should perform authorizations and certificate signing.

The haproxy-ingress leader tracks ingress objects that declares the annotation haproxy-ingress.github.io/cert-signer with value acme and a configured secret name for TLS certificate. The annotation kubernetes.io/tls-acme with value "true" will also be used if the command-line option --acme-track-tls-annotation is declared. The secret does not need to exist. A new certificate will be issued if the certificate is old, the secret does not exist or has an invalid certificate, or the domains of the certificate doesn’t cover all the domains configured in the ingress.

Every 24h or the duration configured in the --acme-check-period, and also when the leader changes, all the certificates from all the tracked ingress will be verified. The certificate is also verified whenever the list of the domains or the secret name changes, so the periodic check will, in fact, only issue new certificates when there is 30 days or less to the certificate expires. This duration can be changed with acme-expiring configuration key.

If an authorization fails, the certificate request is re-enqueued to be tried again after 5m. This duration can be changed with --acme-fail-initial-duration command-line option. If the request fails again, it will be re-enqueued after the double of the time, in this case, after 10m. The duration will exponentially increase up to 8h or the duration defined by the command-line option --acme-fail-max-duration. The request will continue in the work queue until it is successfully processed and stored, or when the ingress object is untracked, either removing the annotation, removing the secret name or removing the ingress object itself.

See also:

• acme command-line options doc.

Affinity

Configure if HAProxy should maintain client requests to the same backend server.

• affinity: the only supported option is cookie. If declared, clients will receive a cookie with a hash of the server it should be fidelized to.
• cookie-key: defines a secret key used with the IP address and port number of a backend server to dynamically create a cookie to that server. Defaults to Ingress if not provided.
• session-cookie-domain: configures the domain to which the persistence cookie should be sent. All subdomains of the configured domain will also receive the cookie. The ingress’ hostname must match this configuration, or should be a subdomain, otherwise modern browsers will refuse to accept the cookie. E.g. if the ingress is configured as sub.example.com, the session-cookie-domain value must be only sub.example.com or example.com. If example.com is used, all of its subdomains will receive the cookie. This option has precedence over session-cookie-shared. Note that, although hostname related, this is a backend scoped configuration key, so the configuration will conflict if used in two or more distinct ingress, with distinct values, pointing to the same Kubernetes service. See backend scope for further information about configuration conflict.
• session-cookie-dynamic: indicates whether or not dynamic cookie value will be used. With the default of true, a cookie value will be generated by HAProxy using a hash of the server IP address, TCP port, and dynamic cookie secret key. When false, the server name will be used as the cookie name. Note that setting this to false will have no impact if use-resolver is set.
• session-cookie-keywords: additional options to the cookie option like nocache, httponly. For the sake of backwards compatibility the default is indirect nocache httponly if not declared and strategy is insert.
• session-cookie-name: the name of the cookie. INGRESSCOOKIE is the default value if not declared.
• session-cookie-preserve: indicates whether the session cookie will be set to preserve mode. If this mode is enabled, haproxy will allow backend servers to use a Set-Cookie HTTP header to emit their own persistence cookie value, meaning the backend servers have knowledge of which cookie value should route to which server. Since the cookie value is tightly coupled with a particular backend server in this scenario, this mode will cause dynamic updating to understand that it must keep the same cookie value associated with the same backend server. If this is disabled, dynamic updating is free to assign servers in a way that can make their cookie value no longer matching.
• session-cookie-same-site: if true, adds the SameSite=None; Secure attributes, which configures the browser to send the persistence cookie with both cross-site and same-site requests. The default value is false, which means only same-site requests will send the persistence cookie.
• session-cookie-shared: defines if the persistence cookie should be shared between all domains that uses this backend. Defaults to false. If true the Set-Cookie response will declare all the domains that shares this backend, indicating to the HTTP agent that all of them should use the same backend server. Note that this option is active only for backward compatibility: modern browsers accept only one domain attribute, deprecating how this option builds the persistence cookie configuration. Use session-cookie-domain instead.
• session-cookie-strategy: the cookie strategy to use (insert, rewrite, prefix). insert is the default value if not declared.
• session-cookie-value-strategy: the strategy to use to calculate the cookie value of a server (server-name, pod-uid). server-name is the default if not declared, and indicates that the cookie will be set based on the name defined in backend-server-naming. pod-uid indicates that the cookie will be set to the UID of the pod running the target server.

Note for dynamic-scaling users only, v0.5 or older: the hash of the server is built based on it’s name. When the slots are scaled down, the remaining servers might change it’s server name on HAProxy configuration. In order to circumvent this, always configure the slot increment at least as much as the number of replicas of the deployment that need to use affinity. This limitation was removed on v0.6.

See also:

• https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Set-Cookie
• https://docs.haproxy.org/2.4/configuration.html#4-cookie
• https://docs.haproxy.org/2.4/configuration.html#5.2-cookie
• https://www.haproxy.com/blog/load-balancing-affinity-persistence-sticky-sessions-what-you-need-to-know/
• https://docs.haproxy.org/2.4/configuration.html#dynamic-cookie-key

Agent check

Allows HAProxy agent checks to be defined for a backend. This is an auxiliary check that is run independently of a regular health check and can be used to control the reported status of a server as well as the weight to be used for load balancing.

• agent-check-port: Defines the port on which the agent is listening. This option is required in order to use an agent check.
• agent-check-addr: Defines the address for agent checks. If omitted, the server address will be used.
• agent-check-interval: Defines the interval between agent checks. If omitted, the default of 2 seconds will be used.
• agent-check-send: Defines a string to be sent to the agent upon connection.

The following limitations are known when using agent-check to change the weight of a backend server:

• If using drain-support, the backend server will have its initial weight defined as 0 (zero) if the server is terminating when haproxy is restarted, making the weight update useless
• Blue/green annotation might be dynamically applied, which will temporarily overwrite the weight defined from the agent

See also:

• https://docs.haproxy.org/2.4/configuration.html#5.2-agent-check
• https://docs.haproxy.org/2.4/configuration.html#5.2-agent-port
• https://docs.haproxy.org/2.4/configuration.html#5.2-agent-inter
• https://docs.haproxy.org/2.4/configuration.html#5.2-agent-send

Allowlist

Defines a comma-separated list of source IPs or CIDRs allowed or denied to connect. The default behavior is to allow all source IPs if neither the allow list nor the deny list are declared. The lists support IPv4 and IPv6.

This is a path scoped configuration: distinct paths in the same hostname can have distinct configurations. However this doesn’t happen if the backend has ssl-passthrough, which uses HAProxy’s TCP mode, in this case the allow and deny lists act as a backend scoped config.

Since v0.12 IPs or CIDRs can be prefixed with !, which means an exception to the rule, so an allow list with "10.0.0.0/8,!10.100.0.0/16" will allow only IPs from the range 10.x.x.x, except the range 10.100.x.x which will continue to be denied.

• allowlist-source-range: Used to deny requests by default, allowing only the IPs and CIDRs in the list, except IPs and CIDRs prefixed with ! which will continue to be denied. whitelist-source-range is an alias to preserve backward compatibility, and will be ignored if allowlist-source-range is declared.
• denylist-source-range: Used to allow requests by default, denying only the IPs and CIDRs in the list, except IPs and CIDRs prefixed with ! which will continue to be allowed.
• allowlist-source-header: Used to define a header from which source IP will be taken in order to compare with the allow and deny list. If not defined a normal source will be used. This option is useful when ingress is hidden behind reverse proxy but you still want to control access to separate paths from ingress configuration.

Allowlist and denylist can be used together. The request will be denied if the configurations overlap and a source IP matches both the allowlist and denylist.

See also:

• https://docs.haproxy.org/2.4/configuration.html#4.2-http-request%20deny
• https://docs.haproxy.org/2.4/configuration.html#4.2-http-request%20set-src

App root

Defines a distinct application root path. HAProxy will redirect requests to the configured path, using 302 status code, when the HTTP client sends a request to the root context of the configured domain. app-root key binds to the root context path, so it needs to be declared in the same Ingress that configures it.

See also:

• Redirect configuration keys.

Auth Basic

Configures Basic Authentication options.

• auth-secret: A secret name with users and passwords used to configure basic authentication. The secret can be in the same namespace of the Ingress resource, or any other namespace if cross namespace is enabled. Secret in the same namespace does not need to be prepended with namespace/. A filename prefixed with file:// can be used containing the list of users and passwords, eg file:///dir/users.list.
• auth-realm: Optional, configures the authentication realm string. localhost will be used if not provided.

The secret referenced by auth-secret should have a key named auth with users and passwords, one per line. The following two formats are supported and both are supported in the same secret or file:

• <user>::<password>: User and password are separated by 2 (two) colons. The password will be copied verbatim, stored in the configuration file in an insecure way.
• <user>:<password-hash>: User and password are separated by 1 (one) colon. This syntax needs a password hash that can be generated with mkpasswd.

See also:

• –allow-cross-namespace command-line option
• Auth TLS configuration keys
• Auth Basic example page

Auth External

Configures External Authentication options.

• auth-url: Configures the endpoint(s) of the authentication service. All requests made to the target backend server will be validated by the authentication service before continue, which should respond with 2xx HTTP status code, otherwise the request is considered as failed. In the case of a failure, the backend server is not used and the client receives the response from the authentication service.
• auth-external-placement: Defines where the external service call should be configured. Options are backend and frontend. Default value is backend and this is the value that has the better performance. Use frontend if the external service create HTTP headers used on early stages, e.g. HTTP header routing constraints. Note that placing the external authentication configuration in the frontend comes with a performance penalty, because all the incomming requests will need to evaluate the ACLs of this configuration. Avoid placing too much (dozens) paths in the frontend on high loaded proxies.
• auth-method: Configures the HTTP method used in the request to the external authentication service. Use an asterisk * to copy the same method used in the client request. The default value is GET.
• auth-headers-request: Configures a comma-separated list of header names that should be copied from the client to the authentication service. All HTTP headers will be copied if not declared.
• auth-headers-succeed: Configures a comma-separated list of header names that should be copied from the authentication service to the backend server if the authentication succeed. All HTTP headers will be copied if not declared.
• auth-headers-fail: Configures a comma-separated list of header names that should be copied from the authentication service to the client if the authentication fail. This option is ignored if auth-signin is used. All HTTP headers will be copied if not declared.
• auth-signin: Optional, configures the endpoint of the sign in server used to redirect failed requests. The content is parsed by haproxy as a log-format string and the result is copied verbatim to the Location header of a HTTP 302 response. The default behavior is to use the authentication service response.
• auth-proxy: Optional, changes the name of a frontend proxy and a free TCP port range, used by auth-request.lua script to query the external authentication endpoint.

External service URL

auth-url is the only mandatory option and receives the external authentication service endpoint. The url format is <proto>://<name>[:<port>][<path>], which means:

• <proto>: can be http, https, service or svc.
• <name>: the IP or hostname if http or https, or the name of a service if service. svc is an alias to service. Note that the hostname is resolved to a list of IP when the ingress is parsed and will not be dynamically updated later if the DNS record changes.
• <port>: the port number, must be provided if a service is used and can be omitted if using http or https. If the service uses named ports, use the service’s port.targetPort field value instead.
• <path>: optional, the fully qualified path to the authentication service.

http and https protocols are straightforward: use them to connect to an IP or hostname without any further configuration. http adds the HTTP Host header if a hostname is used, and https adds also the sni extension. Note that https connects in an insecure way and currently cannot be customized. Do NOT use neither http nor https if haproxy -> authentication service communication has untrusted networks.

svc protocol allows to use a Kubernetes service declared in the same namespace of the ingress or the service being annotated. Services on other namespaces can also be used in the form svc://namespace/servicename:port/path if global config cross-namespace-services was configured as allow. The service can be of any type and a port must always be declared - both in the auth-url configuration and in the service resource. Using svc protocol allows to configure a secure connection, see secure configuration keys and annotate them in the target service.

Configuration examples:

• auth-url: "http://10.0.0.2": Authentication service accepts plain HTTP connection, TCP port 80 and root path are used.
• auth-url: "https://10.0.0.2/auth": Authentication service accepts HTTPS connection, TCP port 443 and path /auth are used.
• auth-url: "https://auth.local:8443": Domain auth.local is resolved during configuration building, and requests will be distributed among all its IPs, using the default load balance algorithm. Authentication service accepts HTTPS connection, TCP port 8443 and root path are used. SNI extension and Host header are added to the request.
• auth-url: "svc://auth-cluster:8443/auth": A service named auth-cluster will be used as the destination of the request, service port 8443 and path /auth. The service can be annotated with Backend and Path scoped configuration keys, eg secure-backends to provide a secure connection.

Forwarding headers

There are three distinct configurations to forward header names:

• auth-headers-request: headers from the client to the authentication service.
• auth-headers-succeed: headers from the authentication service to the backend server.
• auth-headers-fail: headers from the authentication service to the client.

The first option will always be used, the second one only on succeeded requests, the last one only on failures.

These configuration keys can be defined as a comma-separated list of header names. All HTTP headers will be copied if not declared. Each header name can use wildcard. Using a dash - or an empty string instructs the controller not to copy any header.

Configuration examples:

• auth-headers-request: "X-*": copy only headers started with X- from the client to the authentication service. All headers provided by the authentication service will be copied to the backend server if the authentication succeed, or to the client if the authentication fail.
• auth-headers-request: "X-*" and auth-headers-succeed: "X-Token,X-User-*": just like the config above, copy only headers started with X- from the client to the authentication service. If the request succeed, headers started with X-User- and also the header X-Token is copied to the backend server. If the request fail, all the provided headers are copied from the authentication server to the client.

Dependencies and port range

HAProxy Ingress uses auth-request.lua script, which in turn uses HAProxy Technologies’ haproxy-lua-http to perform the authentication request and wait for the response. The request is managed by an internal haproxy frontend/backend pair, which can be fine tuned with auth-proxy. The default value is _front__auth:14415-14499: _front__auth is the name of the frontend helper and 14415-14499 is an unassigned TCP port range that haproxy-lua-http uses to connect and send the authentication request. Requests to this proxy can be added to the log, see auth-log-format configuration key.

See also:

• Auth TLS configuration keys
• OAuth configuration keys
• external-has-lua configuration key.

Auth TLS

Configure client authentication with X509 certificate. The following headers are added to the request:

• X-SSL-Client-SHA1: Hex encoding of the SHA-1 fingerprint of the X509 certificate. The default output uses uppercase hexadecimal digits, configure ssl-fingerprint-lower to true to use lowercase digits instead.
• X-SSL-Client-DN: Distinguished name of the certificate
• X-SSL-Client-CN: Common name of the certificate

These headers can also be added depending on the configuration:

• X-SSL-Client-SHA2: Only if ssl-fingerprint-sha2-bits is declared. Hex encoding of the SHA-2 fingerprint of the X509 certificate. Valid ssl-fingerprint-sha2-bits values are 224, 256, 384 or 512. The default output uses uppercase hexadecimal digits, configure ssl-fingerprint-lower to true to use lowercase digits instead.
• X-SSL-Client-Cert: Only if auth-tls-cert-header is true. Base64 encoding of the X509 certificate in DER format.

The prefix of the header names can be configured with ssl-headers-prefix key. The default value is to X-SSL, which will create a X-SSL-Client-DN header with the DN of the certificate.

The following keys are supported:

• auth-tls-cert-header: If true HAProxy will add X-SSL-Client-Cert http header with a base64 encoding of the X509 certificate provided by the client. Default is to not provide the client certificate.
• auth-tls-error-page: Optional URL of the page to redirect the user if he doesn’t provide a certificate or the certificate is invalid.
• auth-tls-secret: Mandatory secret name with ca.crt key providing all certificate authority bundles used to validate client certificates. Since v0.9, an optional ca.crl key can also provide a CRL in PEM format for the server to verify against. A filename prefixed with file:// can be used containing the CA bundle in PEM format, and optionally followed by a comma and the filename with the crl, eg file:///dir/ca.pem or file:///dir/ca.pem,/dir/crl.pem.
• auth-tls-strict: Defines if a wrong or incomplete configuration, eg missing secret with ca.crt, should forbid connection attempts. If false, a wrong or incomplete configuration will ignore the authentication config, allowing anonymous connection. If true, a strict configuration is used: all requests will be rejected with HTTP 495 or 496, or redirected to the error page if configured, until a proper ca.crt is provided. Strict configuration will only be used if auth-tls-secret has a secret name and auth-tls-verify-client is missing or is not configured as off. This options used to have false as the default value up to v0.13, changing its default to true since v0.14 to improve security.
• auth-tls-verify-client: Optional configuration of Client Verification behavior. Supported values are off, on, optional and optional_no_ca. The default value is on if a valid secret is provided, off otherwise. optional makes the certificate optional but validates it when provided by the client. From v0.8 to v0.13 controller versions, optional_no_ca used to validate the certificate as well, since v0.14 it makes the proxy bypass any validation.
• ssl-fingerprint-lower: Defines if the certificate fingerprint should be in lowercase hexadecimal digits. The default value is false, which uses uppercase digits.
• ssl-fingerprint-sha2-bits: Defines the number of bits of the SHA-2 fingerprint of the client certificate. Valid values are 224, 256, 384 or 512. The header X-SSL-Client-SHA2 will only be added if this option is declared.
• ssl-headers-prefix: Configures which prefix should be used on HTTP headers. Since RFC 6648 X- prefix on unstandardized headers changed from a convention to deprecation. This configuration allows to select which pattern should be used on header names.

See also:

• example page.

Backend protocol

Defines the HTTP protocol version of the backend. Note that HTTP/2 is only supported if HTX is enabled. A case insensitive match is used, so either h1 or H1 configures HTTP/1 protocol. A non SSL/TLS configuration does not overrides secure-backends, so h1 and secure-backends true will still configures SSL/TLS.

Options:

• h1: the default value, configures HTTP/1 protocol. http is an alias to h1.
• h1-ssl: configures HTTP/1 over SSL/TLS. https is an alias to h1-ssl.
• h2: configures HTTP/2 protocol. grpc is an alias to h2.
• h2-ssl: configures HTTP/2 over SSL/TLS. grpcs is an alias to h2-ssl.

See also:

• use-htx configuration key to enable HTTP/2 backends.
• secure-backend configuration keys to configure optional client certificate and certificate authority bundle of SSL/TLS connections.
• https://docs.haproxy.org/2.4/configuration.html#5.2-proto

Backend server naming

Configures how to name backend servers.

• sequence: Names backend servers with a prefixed number sequence: srv001, srv002, and so on. This is the default configuration and the preferred option if dynamic update is used. seq is an alias to sequence.
• pod: Uses the k8s pod name as the backend server name. This option doesn’t work on backends whose service-upstream is true, falling back to sequence.
• ip: Uses target’s <ip>:<port> as the server name.

Backend server ID

When true, each backend server will receive an id in HAProxy config based on the Kubernetes UID of the pod backing it. When using a hash-based balance-algorithm (for example uri or source) together with consistent hashing, this will maintain the stability of assignments when pods are added or removed — that is, a given URI component or source IP will mostly keep hashing to the same server. When this setting is false, an addition or deletion in the server list may disturb the hash assignments of some or all of the remaining servers.

Server IDs can’t dynamically updated, so if this option is enabled, adding or removing a server will cause a reload even when dynamic-scaling is true.

Balance algorithm

Defines a valid HAProxy load balancing algorithm. The default value is roundrobin.

See also:

• https://docs.haproxy.org/2.4/configuration.html#4-balance

Bind

Configures listening IP and port for HTTP/s incoming requests. These configuration keys have backward compatibility with Bind IP addr, Bind port and Fronting proxy keys. The bind configuration keys in this section have precedence if declared.

Any HAProxy supported option can be used, this will be copied verbatim to the bind keyword. See HAProxy bind keyword doc.

Configuration examples:

• bind-http: ":::80" and bind-https: ":::443": Listen all IPv6 addresses
• bind-http: ":80,:::80" and bind-https: ":443,:::443": Listen all IPv4 and IPv6 addresses
• bind-https: ":443,:8443": accept https connections on 443 and also 8443 port numbers

See also:

• https://docs.haproxy.org/2.4/configuration.html#4-bind
• Bind IP addr
• Bind port

Bind IP addr

Define listening IPv4/IPv6 address on public HAProxy frontends. Since v0.10 the default value changed from * to an empty string, which haproxy interprets in the same way and binds on all IPv4 address.

• bind-ip-addr-tcp: IP address of all ConfigMap based TCP services declared on tcp-services-configmap command-line option.
• bind-ip-addr-healthz: IP address of the health check URL.
• bind-ip-addr-http: IP address of all HTTP/s frontends, port :80 and :443, and also fronting-proxy-port if declared.
• bind-ip-addr-prometheus: IP address of the haproxy’s internal Prometheus exporter.
• bind-ip-addr-stats: IP address of the statistics page. See also stats-port.

See also:

• https://docs.haproxy.org/2.4/configuration.html#4-bind
• Bind
• Bind port

Bind port

• healthz-port: Define the port number HAProxy should listen to in order to answer for health checking requests. Use /healthz as the request path.
• http-port: Define the port number of unencrypted HTTP connections.
• https-port: Define the port number of encrypted HTTPS connections.
• prometheus-port: Define the port number of the haproxy’s internal Prometheus exporter. Defaults to not create the listener. A listener without being scraped does not use system resources, except for the listening port. The internal exporter supports scope filter as a query string, eg /metrics?scope=frontend&scope=backend will only export frontends and backends. See the full description in the HAProxy’s Prometheus exporter doc.

See also:

• Bind configuration key
• https://docs.haproxy.org/2.4/configuration.html#4-monitor-uri (healthz-port)
• https://git.haproxy.org/?p=haproxy-2.0.git;a=blob;f=contrib/prometheus-exporter/README;hb=HEAD (prometheus-port)

Blue-green

Configure backend server groups based on the weight of the group - blue/green balance - or a group selection based on http header or cookie value - blue/green selector.

Both blue/green configurations can be used together: if the http header or cookie isn’t provided or doesn’t match a group, the blue/green balance will be used.

Blue/green reads endpoint weight from the pod lister. However the --disable-pod-list command-line option can be safely used to save some memory on clusters with a huge amount of pods. If pod list is disabled, pods are read straight from the k8s api, only when needed, without changing blue/green behavior.

See below the description of the two blue/green configuration options.

Blue/green balance

Configures weight of a blue/green deployment. The annotation accepts a comma separated list of label name/value pair and a numeric weight. Concatenate label name, label value and weight with an equal sign, without spaces. The label name/value pair will be used to match corresponding pods or deploys. There is no limit to the number of label/weight balance configurations.

The endpoints of a single backend are selected using service selectors, which also uses labels. Because of that, in order to use blue/green deployment, the deployment, daemon set or replication controller template should have at least two label name/value pairs - one that matches the service selector and another that matches the blue/green selector.

• blue-green-balance: comma separated list of labels and weights
• blue-green-deploy: deprecated on v0.7, this is an alias to blue-green-balance.
• blue-green-mode: defaults to deploy on v0.7, defines how to apply the weights, might be pod or deploy

The following configuration group=blue=1,group=green=4 will redirect 20% of the load to the group=blue group and 80% of the load to group=green group.

Applying the weights depends on the blue/green mode. v0.6 has only pod mode which means that every single pod receives the same weight as configured on blue/green balance. This means that a balance configuration with 50% to each group will redirect twice as much requests to a backend that has the double of replicas. v0.7 has also deploy mode which rebalance the weights based on the number of replicas of each deployment.

In short, regarding blue/green mode: use pod if you want to redirect more requests to a deployment updating the number of replicas; use deploy if you want to control the load of each side updating the blue/green balance annotation.

Value of 0 (zero) can also be used as weight. This will let the endpoint configured in the backend accepting persistent connections - see affinity - but will not participate in the load balancing. The maximum weight value is 256.

Blue/green selector

Configures header or cookie name and also a pod label name used to tag the group of backend servers.

• blue-green-cookie: the CookieName:LabelName pair
• blue-green-header: the HeaderName:LabelName pair

The CookieName or HeaderName is the name of the http cookie or header used in the request to match a group name. The LabelName is the name of the pod label used to read the group name of the backend server.

The following configuration X-Server:group on blue-green-header configures HAProxy to try to match a backend server based on the value of its label group. A request with header X-Server: green will match a pod labeled group=green. Cookie configuration follows the same rules.

The name of the header and the label follow the k8s label naming convention: must consist of alphanumeric characters, -, _ or ., and must start and end with an alphanumeric character.

Both cookie and header based configurations can be used together in the same backend (k8s service), provided that the label name is the same. If the request uses the configured header and cookie, the header will take precedence, and the cookie would be used if the header value provided doesn’t match a healthy backend server.

Note that blue/green selector should be used only on controlled testing scenarios because it doesn’t provide a proper load balancing: the first healthy backend server that match header or cookie configuration will be used despite if a proper load balance algorithm would choose another one. This can be changed in the future. Blue/green balance doesn’t have this limitation and properly uses the chosen load balance algorithm.

See also:

• example page.
• disable-pod-list command-line option doc.
• https://docs.haproxy.org/2.4/configuration.html#5.2-weight (weight based balance)
• https://docs.haproxy.org/2.4/configuration.html#4-use-server (use-server based selector)

Close sessions duration

Defines the amount of time used to close active sessions before a stopping instance times out and terminates. A stopping instance is an haproxy that doesn’t listen sockets anymore, has an old configuration, and it’s just waiting remaining connections to terminate.

Long lived sessions, like websockets or TCP connections, are usually closed only when the timeout-stop of the old instance expires. Depending on how the clients are configured, all the disconnected clients will reconnect almost at the same time. close-sessions-duration configures the amount of time used to fairly distribute the sessions shutdown, so distributing client reconnections to the new HAProxy instance.

The default behavior is to not anticipate the disconnections, so all the active sessions will be closed at the same time when timeout-stop expires. close-sessions-duration will only take effect if timeout-stop configuration key and --track-old-instances command-line option are also configured.

The duration needs a suffix, which can be a time suffix like s (seconds), m (minutes) or h (hours), or a % that represents a percentage of the timeout-stop configuration:

• 10m means that the last 10 minutes of the timeout-stop will be used to distribute sessions shutdown
• 10% and a timeout-stop of 1h, means that the last 6 minutes of the timeout-stop will be used to distribute sessions shutdown

If the suffix is a time unit, the resulting value should be lower than the timeout-stop configuration. If the suffix is a percentage, the value should be between 2% and 98%.

See also:

• track-old-instances command-line option
• timeout-stop configuration key

Configuration snippet

Add HAProxy configuration snippet to the configuration file. Use multiline content to add more than one line of configuration.

• config-backend: Adds a configuration snippet to a HAProxy backend section.
• config-defaults: Adds a configuration snippet to the end of the HAProxy defaults section.
• config-frontend: Adds a configuration snippet to the HTTP and HTTPS frontend sections, alias for config-frontend-late.
• config-frontend-early: Adds a configuration snippet to the HTTP and HTTPS frontend sections, before any builtin logic.
• config-frontend-late: Adds a configuration snippet to the HTTP and HTTPS frontend sections, same as config-frontend.
• config-global: Adds a configuration snippet to the end of the HAProxy global section.
• config-proxy: Adds a configuration snippet to any HAProxy proxy - listen, frontend or backend. It accepts a multi section configuration, where the name of the section is the name of a HAProxy proxy without the listen/frontend/backend prefix. A section whose proxy is not found is ignored. The content of each section should be indented, the first line without indentation is the start of a new section which will configure another proxy.
• config-sections: Allows to declare new HAProxy sections. The configuration is used verbatim, without any indentation or validation.
• config-tcp: Adds a configuration snippet to the ConfigMap based TCP sections.
• config-tcp-service: Adds a configuration snippet to a TCP service section.

Examples - ConfigMap:

    config-global: |
      tune.bufsize 32768      

    config-defaults: |
      option redispatch      

    config-tcp: |
      tcp-request content reject if !{ src 10.0.0.0/8 }      

    config-proxy: |
      _tcp_default_postgresql_5432
          tcp-request content reject if !{ src 10.0.0.0/8 }
      _front__tls
          tcp-request content reject if !{ src 10.0.0.0/8 } { req.ssl_sni -m reg ^intra\..* }      

    config-sections: |
      cache icons
          total-max-size 4
          max-age 240
      ring myring
          format rfc3164
          maxlen 1200
          size 32764
          timeout connect 5s
          timeout server 10s
          server syslogsrv 127.0.0.1:6514 log-proto octet-count      

    config-frontend: |
      capture request header X-User-Id len 32      

    config-frontend-early: |
      tcp-request connection reject if !{ src 10.0.0.0/8 }      

    config-frontend-late: |
      capture request header X-User-Id len 32      

Annotations:

    annotations:
      haproxy-ingress.github.io/config-backend: |
        acl bar-url path /bar
        http-request deny if bar-url
        http-request set-var(txn.path) path
        http-request cache-use icons if { var(txn.path) -m end .ico }
        http-response cache-store icons if { var(txn.path) -m end .ico }        

    annotations:
      haproxy-ingress.github.io/config-tcp-service: |
        timeout client 1m
        timeout connect 15s        

Connection

Configuration of connection limits.

• max-connections: Define the maximum concurrent connections on all proxies. Defaults to 2000 connections, which is also the HAProxy default configuration.
• maxconn-server: Defines the maximum concurrent connections each server of a backend should receive. If not specified or a value lesser than or equal zero is used, an unlimited number of connections will be allowed. When the limit is reached, new connections will wait on a queue.
• maxqueue-server: Defines the maximum number of connections should wait in the queue of a server. When this number is reached, new requests will be redispatched to another server, breaking sticky session if configured. The queue will be unlimited if the annotation is not specified or a value lesser than or equal to zero is used.

See also:

• https://docs.haproxy.org/2.4/configuration.html#3.2-maxconn (max-connections)
• https://docs.haproxy.org/2.4/configuration.html#5.2-maxconn (maxconn-server)
• https://docs.haproxy.org/2.4/configuration.html#5.2-maxqueue (maxqueue-server)

CORS

Add CORS headers on OPTIONS http command (preflight) and reponses.

• cors-enable: Enable CORS if defined as true.
• cors-allow-origin: Optional, configures Access-Control-Allow-Origin header which defines the URL that may access the resource. Defaults to *. This option accepts a comma-separated list of origins, the response will be dynamically built based on the Origin request header. If Origin belogs to the list, its content will be sent back to the client in the Access-Control-Allow-Origin header, otherwise the first item of the list will be used.
• cors-allow-origin-regex: Optional, like cors-allow-origin but with regex matching. Defaults to empty. This option accepts a space-separated list of origin regexes, the response will be dynamically built based on the Origin request header. If Origin matches any regex in the list, its content will be sent back to the client in the Access-Control-Allow-Origin header, otherwise cors-allow-origin will be considered. This is why you must also set cors-allow-origin (probably to something other than *) when using this option.
• cors-allow-methods: Optional, configures Access-Control-Allow-Methods header which defines the allowed methods. Default value is GET, PUT, POST, DELETE, PATCH, OPTIONS.
• cors-allow-headers: Optional, configures Access-Control-Allow-Headers header which defines the allowed headers. Default value is DNT,X-CustomHeader,Keep-Alive,User-Agent,X-Requested-With,If-Modified-Since,Cache-Control,Content-Type,Authorization.
• cors-allow-credentials: Optional, configures Access-Control-Allow-Credentials header which defines whether or not credentials (cookies, authorization headers or client certificates) should be exposed. Defaults to true.
• cors-max-age: Optional, configures Access-Control-Max-Age header which defines the time in seconds the result should be cached. Defaults to 86400 (1 day).
• cors-expose-headers: Optional, configures Access-Control-Expose-Headers header which defines what headers are allowed to be passed through to the CORS application. Defaults to not add the header.

See also:

• https://developer.mozilla.org/en-US/docs/Web/HTTP/CORS

CPU map

Define how processes/threads map to CPUs. The default value is generated based on nbthread and nbproc.

• cpu-map: Custom override specifying the cpu mapping behaviour in the format described here.
• use-cpu-map: Set to false to prevent any cpu mapping

See also:

• nbthread configuration key
• nbproc configuration key
• https://docs.haproxy.org/2.4/configuration.html#3.1-cpu-map

Cross Namespace

Defines if resources declared on a namespace can read resources declared on another namespace. Supported values are allow or deny. The default configuration denies access from all cross namespace access.

• cross-namespace-secrets-ca: Allows or denies cross namespace reading of CA bundles and CRL files, used by auth-tls-secret and secure-verify-ca-secret configuration keys.
• cross-namespace-secrets-crt: Allows or denies cross namespace reading of x509 certificates and private keys, used by gateway’s, httpRoute’s and ingress’ tls attribute, and also secure-crt-secret configuration key.
• cross-namespace-secrets-passwd: Allows or denies cross namespace reading of password files, used by auth-secret configuration key.
• cross-namespace-services: Allows or denies cross namespace reading of Kubernetes Service resources, used by auth-url configuration key.

Default Redirect

Define a redirect location of the HAProxy for unknown resources.

• default-backend-redirect: Defines a location in which Ingress should redirect an user if the incoming request doesn’t match any hostname, or the requested path doesn’t match any location within the desired hostname. An internal 404 error page is used if not declared and also if default-backend-service was not configured on command line.

• default-backend-redirect-code: Defines the return code to be used when redirecting a user. Defaults to 302 (Moved Temporarily)

DNS resolvers

Configure dynamic backend server update using DNS service discovery.

The following keys are supported:

• dns-resolvers: Multiline list of DNS resolvers in resolvername=ip:port format
• dns-accepted-payload-size: Maximum payload size announced to the name servers
• dns-timeout-retry: Time between two consecutive queries when no valid response was received, defaults to 1s
• dns-hold-valid: Time a resolution is considered valid. Keep in sync with DNS cache timeout. Defaults to 1s
• dns-hold-obsolete: Time to keep valid a missing IP from a new DNS query, defaults to 0s
• dns-cluster-domain: K8s cluster domain, defaults to cluster.local
• use-resolver: Name of the resolver that the backend should use

See also:

• example page.
• https://docs.haproxy.org/2.4/configuration.html#5.3.2
• https://docs.haproxy.org/2.4/configuration.html#5.2-resolvers
• https://kubernetes.io/docs/concepts/services-networking/dns-pod-service/
• https://kubernetes.io/docs/concepts/services-networking/service/#headless-services

Drain support

Set drain-support to true if you wish to use HAProxy’s drain support for pods that are NotReady (e.g., failing a k8s readiness check) or are in the process of terminating. This option only makes sense with cookie affinity configured as it allows persistent traffic to be directed to pods that are in a not ready or terminating state.

By default, sessions will be redispatched on a failed upstream connection once the target pod is terminated. You can control this behavior by setting drain-support-redispatch flag to false to instead return a 503 failure.

See also:

• disable-pod-list command-line option doc.

Dynamic scaling

The dynamic-scaling option defines if backend updates should always be made starting a new HAProxy instance that will read the new config file (false), or updating the running HAProxy via a Unix socket (true) whenever possible. Despite the configuration, the config files will stay in sync with in memory config. The default value was false up to v0.7 if not declared, changed to true since v0.8.

dynamic-scaling is ignored if the backend uses DNS resolver.

If true HAProxy Ingress will create at least backend-server-slots-increment servers on each backend and update them via a Unix socket without reloading HAProxy. Unused servers will stay in a disabled state. If the change cannot be made via socket, a new HAProxy instance will be started.

Starting on v0.8, a new ConfigMap option slots-min-free can be used to configure the minimum number of free/empty servers per backend. If HAProxy need to be restarted and an backend has less than slots-min-free available servers, another backend-server-slots-increment new empty servers would be created.

Starting on v0.6, dynamic-scaling config will only force a reloading of HAProxy if the number of servers on a backend need to be increased. Before v0.6 a reload will also happen when the number of servers could be reduced.

The following keys are supported:

• dynamic-scaling: Define if dynamic scaling should be used whenever possible
• backend-server-slots-increment: Configures the minimum number of servers, the size of the increment when growing and the size of the decrement when shrinking of each HAProxy backend
• slots-min-free: Configures the minimum number of empty servers a backend should have on every HAProxy restarts

See also:

• https://docs.haproxy.org/2.4/management.html#9.3

External

Defines features that can be found in the external haproxy deployment, if an external deployment is used. These options have no effect if using the embedded haproxy.

• external-has-lua: Define as true if the external haproxy has Lua libraries installed in the operating system. Currently Auth External and OAuth need Lua json module installed (Alpine’s lua-json4 package) and will not work if external-has-lua is not enabled.

See also:

• Auth External configuration keys.
• OAuth configuration keys.
• master-socket command-line option

Forwardfor

Defines X-Forwarded-For header and source address handling.

• forwardfor: Defines how X-Forwarded-For header should be handled, options are add, update, ignore and ifmissing. See details below.
• original-forwarded-for-hdr: Defines a header name for the original X-Forwarded-For header value, if present. Defaults to X-Original-Forwarded-For header, and an empty string disables this header declaration.
• real-ip-hdr: Defines a header name that should receive the source IP address, despite of any X-Forwarded-For configuration. Defaults to X-Real-IP header, and an empty string disables this header declaration.

forwardfor options:

• add: haproxy should generate a X-Forwarded-For header with the source IP address. This is the default option and should be used on untrusted networks.
• update: haproxy should preserve any X-Forwarded-For header, if provided, updating with the source IP address, which should be a fronting TCP or HTTP proxy/load balancer.
• ignore: Do nothing - only send the X-Forwarded-For header if the client provided one, without updating its content.
• ifmissing: Add X-Forwarded-For header only if the incoming request doesn’t provide one.

See also:

• https://docs.haproxy.org/2.4/configuration.html#4-option%20forwardfor
• https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/X-Forwarded-For

Fronting proxy port

A port number to listen to http requests from a fronting proxy that does the ssl offload, eg haproxy ingress behind a cloud load balancers that manages the TLS certificates. https-to-http-port is an alias to fronting-proxy-port.

fronting-proxy-port and http-port can share the same port number, see below what changes in the behaviour.

use-forwarded-proto defines if haproxy should use X-Forwarded-Proto header to decide how to handle requests made to fronting-proxy-port port number.

If use-forwarded-proto is false, the request takes the https route and is handled as if X-Forwarded-Proto header is https, see below. The actual header content is ignored by haproxy and forwarded to the backend if provided.

If use-forwarded-proto is true, the default value, requests made to fronting-proxy-port port number evaluate the X-Forwarded-Proto header to decide how to handle the request:

• If X-Forwarded-Proto header is https:
  • HAProxy will handle the request just like the ssl-offload was made by HAProxy itself - HSTS header is provided if configured and X-SSL-* headers won’t be changed or removed if provided.
• If X-Forwarded-Proto header is http or any other value except https:
  • HAProxy will redirect scheme to https
• If X-Forwarded-Proto header is missing:
  • If fronting-proxy-port has its own port — HAProxy will redirect scheme to https
  • If fronting-proxy-port shares the HTTP port — the request will be handled as plain http, being redirected to https only if ssl-redirect is true, just like if fronting-proxy-port wasn’t configured.

See also:

• Bind
• Bind port

Headers

Configures a list of HTTP header names and the value it should be configured with. More than one header can be configured using a multi-line configuration value. The name of the header and its value should be separated with a colon and/or any amount of spaces.

The following variables can be used in the value:

• %[namespace]: namespace of the ingress or service
• %[service]: name of the service which received the request

Configuration example:

    annotations:
      haproxy-ingress.github.io/headers: |
        x-path: /
        host: %[service].%[namespace].svc.cluster.local        

Health check

Controls server health checks on a per-backend basis.

• health-check-uri: If specified, this changes the default TCP health into an HTTP health check.
• health-check-addr: Defines the address for health checks. If omitted, the server addr will be used.
• health-check-port: Defines the port for health checks. If omitted, the server port will be used.
• health-check-interval: Defines the interval between health checks. The default value 2s is used if omitted.
• health-check-rise-count: The number of successful health checks that must occur before a server is marked operational. If omitted, the default value is 2.
• health-check-fall-count: The number of failed health checks that must occur before a server is marked as dead. If omitted, the default value is 3.
• backend-check-interval: Deprecated, use health-check-interval instead.

See also:

• https://docs.haproxy.org/2.4/configuration.html#4.2-option%20httpchk
• https://docs.haproxy.org/2.4/configuration.html#5.2-addr
• https://docs.haproxy.org/2.4/configuration.html#5.2-port
• https://docs.haproxy.org/2.4/configuration.html#5.2-inter
• https://docs.haproxy.org/2.4/configuration.html#5.2-rise
• https://docs.haproxy.org/2.4/configuration.html#5.2-fall

HSTS

Configure HSTS - HTTP Strict Transport Security. The following keys are supported:

• hsts: true if HSTS response header should be added
• hsts-include-subdomains: true if it should apply to subdomains as well
• hsts-max-age: time in seconds the browser should remember this configuration
• hsts-preload: true if the browser should include the domain to HSTS preload list

See also:

• https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Strict-Transport-Security

HTTP Match

Add HTTP constraints for request routing.

• http-header-match: Add HTTP header with exact match, one header name and value pair per line. The first white space, or colon followed by an optional white space, separates the header name and the match value. the header name is case insensitive while the value is case sensitive.
• http-header-match-regex: Same as http-header-match but using regex match. Anchors are not added, so the value bar would match with foobar and barbaz, while ^bar would only match with barbaz.

More than one annotation can be used at the same time, and more than one match can be used in the same annotation. All the matches from all the annotations will be grouped together, and all of them must evaluate to true in order to the request be accepted and sent to the backend.

Note that any match that potentially changes the backend of a request, like HTTP match, must be running in the HAProxy frontend, so earlier than most of other matching rules. External authentication is an example. See auth-external-placement configuration key if using external authentication to provide headers to HTTP match rules.

Examples

Match the header X-Env with value staging - header name is case insensitive, header value is case sensitive:

    annotations:
      haproxy-ingress.github.io/http-header-match: "X-Env: staging"

Match the header X-Env with value staging, and header X-User with value admin:

    annotations:
      haproxy-ingress.github.io/http-header-match: |
        X-Env: staging
        X-User: admin        

Match the header X-Env with value that matches the regex ^(test|staging)$:

    annotations:
      haproxy-ingress.github.io/http-header-match-regex: |
        X-Env: ^(test|staging)$        

See also:

• auth-external-placement configuration key

HTTP Response

Overwrites the default response payload for all the HAProxy’s generated HTTP responses.

• http-response-<code>: represents all the payload of HAProxy or HAProxy Ingress generated HTTP responses. Change <code> to one of the supported HTTP status code, see Supported codes below.
• http-response-prometheus-root: response used on requests sent to the root context of the prometheus exporter port.

Supported codes

The following list has all the HTTP status codes supported by the controller:

All descriptions with [haproxy] refers to internal HAProxy responses, described in the HAProxy documentation or in the MDN. All the others are handled and issued by HAProxy Ingress configurations.

Syntax

A multi-line configuration is used to customize the response payload on all the configuration keys:

• The very first line: Optional, the HTTP status code of the response, optionally followed by the status reason used on HTTP/1.1 responses. The default value is used if missing. Valid inputs are e.g. 404 or 404 Not Found.
• Lines before the first empty line: Optional HTTP headers, one per line, whose name and value are separated by a colon :. It is recommended to always add content-type header. content-length is always calculated and should not be used.
• Lines after the first empty line: Optional HTTP body. It will be copied verbatim to a Lua script. Any char is allowed here except the ]==] string which is reserved by the controller.

Some general hints about response overwriting:

• Do not create huge responses, the whole overwrite must fit into the internal buffer, which is 16k by default, leaving some room to configured downstream rules to operate. See HAProxy’s errorfile doc.
• Take care with external links, e.g. the overwrite of a 503 error page might lead to another 503 error.
• Only add the status code line if changing the code, otherwise let the controller configure with default values.
• A missing status code and status reason will lead to default values, but missing headers and missing body will lead to, respectively, only the content-length header and an empty body.
• Always add at least the HTTP header content-type with the correct value.
• The HTTP header content-length will be overwritten if used.

Examples

Change the payload type and content, using the default status code and status reason:

  data:
    http-response-404: |
      content-type: text/plain
      connection: close

      404 not found      

Overwrite the Status Code - always add the status reason (see MDN) if changing the status code:

  data:
    http-response-404: |
      302 Found
      location: https://this.other.local      

Response without header and with an empty body:

  data:
    http-response-404: |
      404 Not Found      

Response with the headers only:

  data:
    http-response-404: |
      connection: close      

Response with only the body - discouraged, at least the content-type should be added:

  data:
    http-response-404: |

      not found

See also:

• --default-backend-service command-line option
• proxy-body-size configuration key
• mTLS related configuration keys
• https://docs.haproxy.org/2.4/configuration.html#4-errorfile
• HAProxy’s HTTP response at HAProxy documentation
• HTTP response status codes at MDN

Initial weight

Configures the weight value of each backend server - either the enabled and also the disabled servers. The default value is 1. Changing this value has no effect on the proportional value between each server of a single backend, thus this doesn’t change the balance between the servers.

Change the default value to a higher number, eg 100, if using with agent-check and the agent is used to change the weight of the server.

Blue/green on deploy mode also uses initial-weight as its minimum weight value, provided that the maximum is lesser than or equal 256.

See also:

• agent-check
• https://docs.haproxy.org/2.4/configuration.html#5.2-weight

Limit

Configure rate limit and concurrent connections per client IP address in order to mitigate DDoS attack. If several users are hidden behind the same IP (NAT or proxy), this configuration may have a negative impact for them. Whitelist can be used to these IPs.

The following annotations are supported:

• limit-connections: Maximum number os concurrent connections per client IP
• limit-rps: Maximum number of connections per second of the same IP
• limit-whitelist: Comma separated list of CIDRs that should be removed from the rate limit and concurrent connections check

Load server state

Define if HAProxy should save and reload it’s current state between server reloads, like uptime of backends, qty of requests and so on.

This is an experimental feature and has currently some issues if using with dynamic-scaling: an old state with disabled servers will disable them in the new configuration.

See also:

• https://docs.haproxy.org/2.4/configuration.html#3.1-server-state-file
• https://docs.haproxy.org/2.4/configuration.html#4-load-server-state-from-file

Log format

Customize the tcp, http or https log format using log format variables. Only used if syslog-endpoint is also configured.

• auth-log-format: log format of all auth external frontends. Use default to configure default HTTP log format, defaults to not log.
• http-log-format: log format of all HTTP proxies, defaults to HAProxy default HTTP log format.
• https-log-format: log format of TCP proxy used to inspect SNI extension. Use default to configure default TCP log format, defaults to not log.
• tcp-log-format: log format of the ConfigMap based TCP proxies. Defaults to HAProxy default TCP log format. See also --tcp-services-configmap command-line option.
• tcp-service-log-format: log format of TCP frontends, configured via ingress resources and tcp-service-port configuration key. Defaults to HAProxy default TCP log format.

See also:

• https://docs.haproxy.org/2.4/configuration.html#8.2.4
• syslog
• Auth External configuration keys.
• TCP Services configuration keys.

Master-worker

Configures master-worker related options. These options are only used when --master-worker command-line option is configured as true.

• master-exit-on-failure: If true, kill all the remaining workers and exit from master in the case of an unexpected failure of a worker, eg a segfault.
• worker-max-reloads: Defines how many reloads a haproxy worker should survive before receive a SIGTERM. The default value is 0 which means unlimited. This option limits the number of active workers and the haproxy’s pod memory usage. Useful on workloads with long running connections, eg websockets, and clusters that frequently changes and forces haproxy to reload.

See also:

• External HAProxy example page
• https://docs.haproxy.org/2.4/configuration.html#3.1-master-worker
• https://docs.haproxy.org/2.4/configuration.html#mworker-max-reloads
• master-socket and master-worker command-line options

Modsecurity

Configure modsecurity agent. These options only have effect if modsecurity-endpoints is configured.

Configure modsecurity-endpoints with a comma-separated list of IP:port of HAProxy agents (SPOA) for ModSecurity. The default configuration expects the contrib/modsecurity implementation from HAProxy source code.

Up to v0.7 all http requests will be parsed by the ModSecurity agent, even if the ingress resource wasn’t configured to deny requests based on ModSecurity response. Since v0.8 the spoe filter is configured on a per-backend basis.

The following keys are supported:

• modsecurity-args: Space separated list of arguments that HAProxy will send to the modsecurity agent. You can override this to e.g. prevent sending the request body to modsecurity which will improve performance, but reduce security. The arguments must be valid HAProxy sample fetch methods.
• modsecurity-endpoints: Comma separated list of ModSecurity agent endpoints.
• modsecurity-timeout-connect: Defines the maximum time to wait for the connection to the agent be established. Configures the haproxy’s timeout connect. Defaults to 5s if not configured.
• modsecurity-timeout-hello: Defines the maximum time to wait for the AGENT-HELLO frame from the agent. Default value is 100ms.
• modsecurity-timeout-idle: Defines the maximum time to wait before close an idle connection. Default value is 30s.
• modsecurity-timeout-processing: Defines the maximum time to wait for the whole ModSecurity processing. Default value is 1s.
• modsecurity-timeout-server: Defines the maximum time to wait for an agent response. Configures the haproxy’s timeout server. Defaults to 5s if not configured.
• modsecurity-use-coraza: Defines whether the generated SPOE config should include Coraza-specific values. In order to use Coraza instead of Modsecurity, you must set this to “true” and also set modsecurity-args based on the instructions in the coraza-spoa repository. A full example can be found here.

See also:

• modsecurity example page.
• waf configuration key.
• https://www.haproxy.org/download/2.0/doc/SPOE.txt
• https://docs.haproxy.org/2.4/configuration.html#9.3
• https://github.com/jcmoraisjr/modsecurity-spoa

Nbproc

Define the number of dedicated HAProxy process to the SSL/TLS handshake and offloading. The default value is 0 (zero) which means HAProxy should process all the SSL/TLS offloading, as well as the header inspection and load balancing within the same HAProxy process.

The recommended value depends on how much CPU a single HAProxy process is spending. Use 0 (zero) if the amount of processing has low CPU usage. This will avoid a more complex topology and an inter-process communication. Use the number of cores of a dedicated host minus 1 (one) to distribute the SSL/TLS offloading process. Leave one core dedicated to header inspection and load balancing.

If splitting HAProxy into two or more process and the number of threads is one, cpu-map is used to bind each process on its own CPU core.

See also:

• nbthread configuration key
• cpu-map configuration key
• https://docs.haproxy.org/2.4/configuration.html#3.1-nbproc
• https://docs.haproxy.org/2.4/configuration.html#4-bind-process
• https://docs.haproxy.org/2.4/configuration.html#3.1-cpu-map

Nbthread

Define the number of threads a single HAProxy process should use to all its processing. If not declared, the number of threads will be adjusted to the number of available CPUs on platforms that support CPU affinity.

If using two or more threads, cpu-map is used by default to bind each thread on its own CPU core.

See also:

• cpu-map configuration key
• https://docs.haproxy.org/2.4/configuration.html#3.1-nbthread
• https://docs.haproxy.org/2.4/configuration.html#3.1-cpu-map

OAuth

Configure OAuth2 via Bitly’s oauth2_proxy. These options have less precedence if used with auth-url.

• oauth: Defines the oauth implementation. The only supported option is oauth2_proxy or its alias oauth2-proxy.
• oauth-uri-prefix: Defines the URI prefix of the oauth service. The default value is /oauth2. There should be a backend with this path in the ingress resource.
• oauth-headers: Defines an optional comma-separated list of <header>[:<source>] used to configure request headers to the upstream backend. The default value is X-Auth-Request-Email which copies this HTTP header from oauth2-proxy service response to the backend service. An optional <source> can be provided with another HTTP header or an internal HAProxy variable.

OAuth2 expects oauth2-proxy, or any other compatible implementation running as a backend of the same domain that should be protected. oauth2-proxy has support to GitHub, Google, Facebook, OIDC and others.

Since v0.13 these same options can be used with Auth External configuration keys. Change <oauth2-proxy-service> below with the oauth2-proxy service name, and <hostname> to the hostname of the oauth2-proxy and the backend servers:

• auth-url: "svc://<oauth2-proxy-service>/oauth2/auth".
• auth-signin: "https://<hostname>/oauth2/start?rd=%[path]" - the content is parsed by haproxy as a log-format string and the result is copied verbatim to the Location header of a HTTP 302 response. The rd query field asks oauth2-proxy to preserve the path provided by the client.
• auth-headers-succeed: "X-Auth-Request-Email" - copy the X-Auth-Request-Email HTTP header with the user email from oauth2-proxy to the backend server.

Configure oauth2 on a distinct ingress, without the auth-url annotation, otherwise it will endless loop in a HTTP 403 error.

See also:

• Auth External configuration keys.
• external-has-lua configuration key.
• example page.

Path type

Defines how the path of an incoming request should match a declared path in the ingress object.

• path-type: Configures the path type. Case insensitive, so Begin and begin configures the same path type option. The ingress spec has priority, this option will only be used if the pathType attribute from the ingress spec is declared as ImplementationSpecific.
• path-type-order: Defines a comma-separated list of the order that non overlapping paths should be matched, which means that /dir/sub will always be checked before /dir despite their type and the configured order. Mostly used to define when regex path types should be checked for incoming requests, since HAProxy Ingress doesn’t calculate overlapping from regex paths. All path types must be provided. Case insensitive, use all path types in lowercase.

Supported path-type values:

• begin: Case insensitive, matches the beginning of the path from the incoming request. This is the default value if not declared.
• exact: Case sensitive, matches the whole path. Implements the Exact path type from the ingress spec.
• prefix: Case sensitive, matches a whole subdirectory from the incoming path. A declared /app path matches /app and /app/1 but does not match /app1. Implements the Prefix path type from the ingress spec.
• regex: Case sensitive, matches the incoming path using POSIX extended regular expression. The regular expression has an implicit start ^ and no ending $ boundary, so a declared /app[0-9]+/? will match paths starting with this pattern. Add a trailing $ if an exact match is desired.

Request and match examples:

Proxy body size

Define the maximum number of bytes HAProxy will allow on the body of requests. Default is to not check, which means requests of unlimited size. This limit can be changed per ingress resource.

Since 0.4 a suffix can be added to the size, so 10m means 10 * 1024 * 1024 bytes. Supported suffix are: k, m and g.

Since 0.7 unlimited can also be used to overwrite any global body size limit.

See also:

• https://docs.haproxy.org/2.4/configuration.html#7.3.6-req.body_size

Proxy protocol

Configures PROXY protocol in frontends and backends.

• proxy-protocol: Define if the upstream backends support proxy protocol and what version of the protocol should be used. Supported values are v1, v2, v2-ssl, v2-ssl-cn or no. The default behavior if not declared is that the protocol is not supported by the backends and should not be used.
• use-proxy-protocol: Define if HTTP services are behind another proxy that uses the PROXY protocol. If true, HTTP ports which defaults to 80 and 443 will expect the PROXY protocol, version 1 or 2. The stats endpoint (defaults to port 1936) has its own stats-proxy-protocol configuration key.
• tcp-service-proxy-protocol: Define if the TCP service is behind another proxy that uses the PROXY protocol. Configures as "true" if the proxy should expect requests using the PROXY protocol, version 1 or 2. The default value is "false".

See also:

• https://www.haproxy.org/download/2.0/doc/proxy-protocol.txt
• https://docs.haproxy.org/2.4/configuration.html#5.1-accept-proxy
• https://docs.haproxy.org/2.4/configuration.html#5.2-send-proxy
• https://docs.haproxy.org/2.4/configuration.html#5.2-send-proxy-v2
• https://docs.haproxy.org/2.4/configuration.html#5.2-send-proxy-v2-ssl
• https://docs.haproxy.org/2.4/configuration.html#5.2-send-proxy-v2-ssl-cn

Redirect

Configures HTTP redirect. Redirect from matches source hostnames that should be redirected to the hostname declared in the ingress spec. Redirect to uses the hostname declared in the ingress spec as the matching source and redirects the request to the configured URL. See examples below.

• redirect-from: Defines a source domain using hostname-like syntax, so wildcard domains can also be used. The request is redirected to the configured hostname, preserving protocol, path and query string.
• redirect-from-regex: Defines a POSIX extended regular expression used to match a source domain. The regex will be used verbatim, so add ^ and $ if strict hostname is desired and escape \. dots in order to strictly match them.
• redirect-from-code: Which HTTP status code should be used in the redirect from. A 302 response is used by default if not configured.
• redirect-to: Defines the destination URL to redirect the incoming request. The declared hostname and path are used only to match the request, the backend will not be used and it’s only needed to be declared to satisfy ingress spec validation.
• redirect-to-code: Which HTTP status code should be used in the redirect to. A 302 response is used by default if not configured.
• no-redirect-locations: Defines a comma-separated list of paths that should be ignored by all the redirects. Default value is /.well-known/acme-challenge, used by ACME protocol. Configure as an empty string to make the redirect happen on all paths, including the ACME challenge.

Using redirect-from

The following configuration redirects app.local to www.app.local, preserving protocol, path and query string:

apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  annotations:
    haproxy-ingress.github.io/redirect-from: "app.local"
  name: app
spec:
  rules:
  - host: www.app.local
    http:
      paths:
      - path: /
        pathType: Prefix
        backend:
          service:
            name: app
            port:
              number: 8080

The same source domain can be configured just once, and a target domain can be assigned just once as well, which means that this configuration can only be used on ingress resources that defines just one hostname. The redirect configuration has the lesser precedence, so if a source domain is also configured as a hostname on an ingress spec, or as an alias using annotation, the redirect will not happen.

Using redirect-to

The following configuration redirects app.local/... to https://www.app.local/login, without preserving protocol, path or query string:

Note: www.app.local should be configured on another ingress resource, and app service below will not be used.

apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  annotations:
    haproxy-ingress.github.io/redirect-to: "https://www.app.local/login"
  name: app
spec:
  rules:
  - host: app.local
    http:
      paths:
      - path: /
        pathType: Prefix
        backend:
          service:
            name: app
            port:
              number: 8080

See also:

• app-root configuration key.

Rewrite target

Configures how URI of the requests should be rewritten before send the request to the backend. The following table shows some examples:

Secure backend

Configure secure (TLS) connection to the backends.

• secure-backends: Define as true if the backend provide a TLS connection.
• secure-crt-secret: Optional secret name of client certificate and key. This cert/key pair must be provided if the backend requests a client certificate. Expected secret keys are tls.crt and tls.key, the same used if secret is built with kubectl create secret tls <name>. A filename prefixed with file:// can also be used, containing both certificate and private key in PEM format, eg file:///dir/crt.pem.
• secure-sni: Optional hostname that should be used as the SNI TLS extension sent to the backend server. If host is used as the content, the header Host from the incoming request is used as the SNI extension in the request to the backend. sni can also be used, which will use the same SNI from the incoming request. Note that, although the header Host is always right, the incoming SNI might be wrong if a TLS connection that’s already opened is reused - this is a common practice on browsers connecting over http2. Any other value different of host or sni will be used verbatim and should be a valid domain. If secure-verify-ca-secret is also provided, this hostname is also used to validate the server certificate names.
• secure-verify-ca-secret: Optional but recommended secret name with certificate authority bundle used to validate server certificate, preventing man-in-the-middle attacks. Expected secret key is ca.crt. Since v0.9, an optional ca.crl key can also provide a CRL in PEM format for the server to verify against. A filename prefixed with file:// can be used containing the CA bundle in PEM format, and optionally followed by a comma and the filename with the crl, eg file:///dir/ca.pem or file:///dir/ca.pem,/dir/crl.pem. Configure either secure-sni or secure-verify-hostname to verify the certificate name.
• secure-verify-hostname: Optional hostname used to verify the name of the server certificate, without using the SNI TLS extension. This option can only be used if secure-verify-ca-secret was provided, and only supports hardcoded domains which is used verbatim.

See also:

• Backend protocol configuration key.
• https://docs.haproxy.org/2.4/configuration.html#5.2-verify
• https://docs.haproxy.org/2.4/configuration.html#5.2-verifyhost
• https://docs.haproxy.org/2.4/configuration.html#5.2-sni

Security

Change security options for deployments starting as root user.

• username and groupname: Changes the user and group names used to run haproxy as non root. The default value is an empty string, which means leave haproxy running as root. Note that even running as root, haproxy always drops its own privileges before start its event loop. Both options should be declared to the configuration take effect.
• use-chroot: If true, configures haproxy to perform a chroot() in the empty and non-writable directory /var/empty during the startup process, just before it drops its own privileges. See Using chroot() section below.
• use-haproxy-user: If true, configures username and groupname configuration keys as haproxy. See username and groupname above. Note that this user and group exists in the embedded haproxy, and should exist in the external haproxy if used. In the case of a conflict, username and groupname declaration will have priority and use-haproxy-user will be ignored. If false, the default value, user and group names will not be changed.

Starting as root

In the default configuration HAProxy Ingress container starts as the non root user haproxy, UID 99. Since its 2.4 version, docker.io/haproxy image starts as the same user and UID.

Starting as root can be useful to configure chroot, and Security Considerations from the HAProxy doc describes some other use cases.

The starting user can be changed in the deployment or daemonset’s pod template using the following configuration:

...
  template:
    spec:
      securityContext:
        runAsUser: 0

Configuring the Helm chart:

controller:
  securityContext:
    runAsUser: 0

Using chroot()

Beware of some chroot limitations:

See also:

• https://docs.haproxy.org/2.4/management.html#13
• https://docs.haproxy.org/2.4/configuration.html#3.1-chroot
• https://docs.haproxy.org/2.4/configuration.html#3.1-uid
• https://docs.haproxy.org/2.4/configuration.html#3.1-gid
• https://docs.haproxy.org/2.4/configuration.html#3.1-unix-bind

Server alias

Configure hostname alias. All annotations will be combined together with the host attribute in the same ACL, and any of them might be used to match SNI extensions (TLS) or Host HTTP header. The matching is case insensitive.

• server-alias: Defines an alias with hostname-like syntax. On v0.6 and older, wildcard * wasn’t converted to match a subdomain. Regular expression was also accepted but dots were escaped, making this alias less useful as a regex. Starting v0.7 the same hostname syntax is used, so *.my.domain will match app.my.domain but won’t match sub.app.my.domain.
• server-alias-regex: Only in v0.7 and newer. Match hostname using a POSIX extended regular expression. The regex will be used verbatim, so add ^ and $ if strict hostname is desired and escape \. dots in order to strictly match them. Some HTTP clients add the port number in the Host header, so remember to add (:[0-9]+)?$ in the end of the regex if a dollar sign $ is being used to match the end of the string.

Service upstream

Defines if the HAProxy backend/server endpoints should be configured with the service VIP/IPVS. If false, the default value, the endpoints will be used and HAProxy will load balance the requests between them. If defined as true the service’s ClusterIP is used instead.

Source Address Intf

Configures a list of network interface names whose IPv4 address should be used as the source address for outgoing connections.

• source-address-intf: Comma separated list of network interface names

As the default behavior, HAProxy will leave the operating system choose the most appropriate address. However the same source address will be used, even if the network interface has more IP address or other interfaces can also reach the destination, leading to outgoing TCP port exhaustion on deployments that needs more than 64k concurrent connections. Using more source IPs allows to bypass the maximum of 64k concurrent connections per instance.

HAProxy Ingress will list all IPv4 from all provided interfaces, ignoring interfaces that cannot be found, does not have IPv4, or cannot list its IPs. The IP addresses will be distributed among all the servers/endpoints, where each distinct server will use an IP from the list as its source address for its outgoing connections. If there are more replicas than IPs, some IPs from the list will be used more than once. If there are more IPs than replicas, some of the IPs from the list will not be used in a particular backend, but can be used on others that shares the configuration. The IP distribution consistently starts on distinct positions on distinct backends, fairly distributing all the IPs from the list on workloads with a big amount of backends with one or so servers each. If all the interfaces failed to list IP address, HAProxy falls back to the default behavior and leaves the operating system to choose the source IP.

Update also /proc/sys/net/ipv4/ip_local_port_range in the HAProxy hosts to allow each source IP use more than its default 28k ephemeral ports.

See also:

• https://docs.haproxy.org/2.4/configuration.html#4-source
• https://docs.haproxy.org/2.4/configuration.html#5.2-source
• https://www.kernel.org/doc/html/v5.12/networking/ip-sysctl.html#ip-variables

SSL always add HTTPS

Every hostname declared on an Ingress resource is added to an internal HTTP map. If at least one Ingress adds the hostname in the tls attribute, the hostname is also added to an internal HTTPS map and does ssl offload using the default certificate. A secret name can also be added in the tls attribute, overriding the certificate used in the TLS handshake.

ssl-always-add-https asks the controller to always add the domain in the internal HTTP and HTTPS maps, even if the tls attribute isn’t declared. If false, a missing tls attribute will only declare the domain in the HTTP map and ssl-redirect is ignored. If true, a missing tls attribute adds the domain in the HTTPS map, and the TLS handshake will use the default certificate. If tls attribute is used, this configuration is ignored.

ssl-always-follow-redirect configures how the ssl-redirect option should be used when the tls attribute is missing, but the host is added in the HTTPS map. When false, it makes the controller to mimic a v0.11 and older behavior by not redirecting to HTTPS if the ingress does not declare the tls attribute. When true, SSL redirect will happen if configured, regardless the presence of the tls attribute. This option is ignored if ssl-always-add-https is false.

The default value for ssl-always-add-https is false since v0.13 to correctly implement Ingress spec. The default value can be globally changed in the global ConfigMap.

These options are implemented to help teams upgrade from older controller versions without disruptions. It is suggested not to be changed, and if so, it is also suggested to evolve ingress resources to a state that does not depend on it in the mid term.

SSL ciphers

Set the list of cipher algorithms used during the SSL/TLS handshake.

• ssl-cipher-suites: Cipher suites on TLS v1.3 handshake of incoming requests. HAProxy being the TLS server.
• ssl-cipher-suites-backend: Cipher suites on TLS v1.3 handshake to backend/servers. HAProxy being the TLS client.
• ssl-ciphers: Cipher suites on TLS up to v1.2 handshake of incoming requests. HAProxy being the TLS server.
• ssl-ciphers-backend: Cipher suites on TLS up to v1.2 handshake to backend/servers. HAProxy being the TLS client.

Default values on HAProxy Ingress up to v0.8:

• TLS up to v1.2: ECDHE-RSA-AES128-GCM-SHA256:ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-RSA-AES256-GCM-SHA384:ECDHE-ECDSA-AES256-GCM-SHA384:DHE-RSA-AES128-GCM-SHA256:DHE-DSS-AES128-GCM-SHA256:kEDH+AESGCM:ECDHE-RSA-AES128-SHA256:ECDHE-ECDSA-AES128-SHA256:ECDHE-RSA-AES128-SHA:ECDHE-ECDSA-AES128-SHA:ECDHE-RSA-AES256-SHA384:ECDHE-ECDSA-AES256-SHA384:ECDHE-RSA-AES256-SHA:ECDHE-ECDSA-AES256-SHA:DHE-RSA-AES128-SHA256:DHE-RSA-AES128-SHA:DHE-DSS-AES128-SHA256:DHE-RSA-AES256-SHA256:DHE-DSS-AES256-SHA:DHE-RSA-AES256-SHA:!aNULL:!eNULL:!EXPORT:!DES:!RC4:!3DES:!MD5:!PSK

Default values on HAProxy Ingress v0.9 and newer:

• TLS up to v1.2: ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-RSA-AES128-GCM-SHA256:ECDHE-ECDSA-AES256-GCM-SHA384:ECDHE-RSA-AES256-GCM-SHA384:ECDHE-ECDSA-CHACHA20-POLY1305:ECDHE-RSA-CHACHA20-POLY1305:DHE-RSA-AES128-GCM-SHA256:DHE-RSA-AES256-GCM-SHA384
• TLS v1.3: TLS_AES_128_GCM_SHA256:TLS_AES_256_GCM_SHA384:TLS_CHACHA20_POLY1305_SHA256

ssl-ciphers and ssl-cipher-suites were Global scope up to v0.10.

See also:

• https://ssl-config.mozilla.org/#server=haproxy
• https://docs.haproxy.org/2.4/configuration.html#3.1-ssl-default-bind-ciphers
• https://docs.haproxy.org/2.4/configuration.html#3.1-ssl-default-bind-ciphersuites
• https://docs.haproxy.org/2.4/configuration.html#5.2-ciphers
• https://docs.haproxy.org/2.4/configuration.html#5.2-ciphersuites

SSL DH

Configures Diffie-Hellman key exchange parameters.

• ssl-dh-param: Configure the secret name which defines the DH parameters file used on ephemeral Diffie-Hellman key exchange during the SSL/TLS handshake. A filename prefixed with file:// can be used containing the DH parameters file in PEM format, eg file:///dir/dh-param.pem.
• ssl-dh-default-max-size: Define the maximum size of a temporary DH parameters used for key exchange. Only used if ssl-dh-param isn’t provided.

See also:

• https://docs.haproxy.org/2.4/configuration.html#tune.ssl.default-dh-param
• https://docs.haproxy.org/2.4/configuration.html#3.1-ssl-dh-param-file

SSL engine

Set the name of the OpenSSL engine to use. The string shall include the engine name and its parameters.

Additionally, ssl-mode-async can be set to enable asynchronous TLS I/O operations if the ssl-engine used supports it.

Reference:

• https://docs.haproxy.org/2.4/configuration.html#ssl-engine
• https://docs.haproxy.org/2.4/configuration.html#ssl-mode-async

SSL options

Define a space-separated list of options on SSL/TLS connections.

• ssl-options: Default options for all the TLS frontend connections - HAProxy being the server
• ssl-options-backend: Options for backend server connections - HAProxy being the client
• ssl-options-host: Options for TLS frontend connections - HAProxy being the server. This acts as a host scoped override to options defined in ssl-options and supports everything that HAProxy supports in the crt-list.

Default values for ssl-options and ssl-options-backend:

• v0.9 and newer: no-sslv3 no-tlsv10 no-tlsv11 no-tls-tickets
• up to v0.8: no-sslv3 no-tls-tickets

Supported options for ssl-options and ssl-options-backend:

• force-sslv3: Enforces use of SSLv3 only
• force-tlsv10: Enforces use of TLSv1.0 only
• force-tlsv11: Enforces use of TLSv1.1 only
• force-tlsv12: Enforces use of TLSv1.2 only
• no-sslv3: Disables support for SSLv3
• no-tls-tickets: Enforces the use of stateful session resumption
• no-tlsv10: Disables support for TLSv1.0
• no-tlsv11: Disables support for TLSv1.1
• no-tlsv12: Disables support for TLSv1.2

New supported options since v0.9 for ssl-options and ssl-options-backend:

• force-tlsv13: Enforces use of TLSv1.3 only
• no-tlsv13: Disables support for TLSv1.3
• ssl-max-ver <SSLv3|TLSv1.0|TLSv1.1|TLSv1.2|TLSv1.3>: Enforces the use of a SSL/TLS version or lower
• ssl-min-ver <SSLv3|TLSv1.0|TLSv1.1|TLSv1.2|TLSv1.3>: Enforces the use of a SSL/TLS version or upper

See also:

• https://docs.haproxy.org/2.4/configuration.html#5.1-crt-list

SSL passthrough

Defines if HAProxy should work in TCP proxy mode and leave the SSL offload to the backend. SSL passthrough is a per domain configuration, which means that other domains can be configured to SSL offload on HAProxy.

• ssl-passthrough: Enable SSL passthrough if defined as true. The backend is then expected to SSL offload the incoming traffic. The default value is false, which means HAProxy should do the SSL handshake.
• ssl-passthrough-http-port: Optional HTTP port number of the backend. If defined, connections to the HAProxy’s HTTP port, defaults to 80, is sent to the configured port number of the backend, which expects to speak plain HTTP. If not defined, connections to the HTTP port will redirect the client to HTTPS.

Hostnames configured as ssl-passthrough configures HAProxy in the following way:

• Requests to the HTTPS port, defaults to 443, will be sent to the backend and port number configured in the root / path of the domain. Such port must speak TLS and will make the TLS handshake with the client. There is no path inspection, so only one backend is supported.
• Requests to the HTTP port, defaults to 80, will follow the same rules of non ssl-passthrough domains: if the request matches a non root path, the configured backend will be used and it should speak plain HTTP, except if secure-backends is also configured. If there isn’t non root paths or if they doesn’t match, the request will fall back to: redirect to HTTPS (default), or the request will be sent to ssl-passthrough-http-port port number of the ssl backend.

SSL redirect

Configures if an encrypted connection should be used.

• ssl-redirect: Defines if HAProxy should send a 302 redirect response to requests made on unencrypted connections. Note that this configuration will only make effect if TLS is configured.
• ssl-redirect-code: Defines the HTTP status code used in the redirect. The default value is 302 if not declared. Supported values are 301, 302, 303, 307 and 308.
• no-tls-redirect-locations: Defines a comma-separated list of URLs that should be removed from the TLS redirect. Requests to :80 http port and starting with one of the URLs from the list will not be redirected to https despite of the TLS redirect configuration. This option defaults to /.well-known/acme-challenge, used by ACME protocol.

See also:

• ssl-always-add-https configuration key
• https://docs.haproxy.org/2.4/configuration.html#redirect

Stats

Configurations of the HAProxy statistics page:

• stats-auth: Enable basic authentication with clear-text password - <user>:<passwd>
• stats-port: Change the port HAProxy should listen to requests
• stats-proxy-protocol: Define if the stats endpoint should enforce the PROXY protocol
• stats-ssl-cert: Optional namespace/secret-name of tls.crt and tls.key pair used to enable SSL on stats page. A filename prefixed with file:// can be used, containing both certificate and private key in PEM format, eg file:///dir/crt.pem. Plain http will be used if not provided, the secret wasn’t found, the secret doesn’t have a crt/key pair or the file is not found.

Strict host

Defines whether the path of another matching host/FQDN should be used to try to serve a request. The default value is false, which means all matching wildcard hosts will be visited in order to try to match the path. If true, a strict configuration is applied and the default-backend should be used if a path couldn’t be matched.

Using the following configuration:

  spec:
    rules:
    - host: my.domain.com
      http:
        paths:
        - path: /a
          backend:
            serviceName: svc1
            servicePort: 8080
    - host: *.domain.com
      http:
        paths:
        - path: /
          backend:
            serviceName: svc2
            servicePort: 8080

A request to my.domain.com/b would serve:

• svc2 if strict-host is false, the default value
• default-backend if strict-host is true

Syslog

Logging configurations.

• syslog-endpoint: Configures the UDP syslog endpoint where HAProxy should send access logs.
• syslog-format: Configures the log format to be either rfc5424 (default), rfc3164 or raw.
• syslog-length: The maximum line length, log lines larger than this value will be truncated. Defaults to 1024.
• syslog-tag: Configure the tag field in the syslog header to the supplied string.

The HAProxy process can also send logs to stdout, instead of an external syslog endpoint or a syslog sidecar, by following the steps below:

• Configure syslog-endpoint as stdout and syslog-format as raw
• From v0.12 and newer, configure HAProxy to run as a sidecar, see the example page
• From v0.14 and newer, it is also possible to make embedded HAProxy send logs to the controller container by adding --master-worker command-line option - in this case, both controller and haproxy logs will share the same stream

See also:

• https://docs.haproxy.org/2.4/configuration.html#3.1-log
• https://docs.haproxy.org/2.4/configuration.html#3.1-log-tag

TCP Services

Configures a TCP proxy.

• tcp-service-port: Defines the port number HAProxy should listen to.

By default ingress resources configure HTTP services, and incoming requests are routed to backend servers based on hostnames and HTTP path. Whenever the tcp-service-port configuration key is added to an ingress resource, incoming requests are processed as TCP requests and the listening port number is used to route requests, using a dedicated frontend in tcp mode. Optionally, the TLS SNI extension can also be used to route incoming request if the hostname is declared in the ingress spec.

Due to the limited data that can be inspected on TCP requests, a limited number of configuration keys work with TCP services:

• Backend and Path scoped configuration keys work, provided that they are not HTTP related - eg Cors and HSTS are ignored by TCP services, on the other hand balance algorithm, Allow list and Blue/green work just like in the HTTP requests counterpart.
• All Global configuration keys related with the whole haproxy process will also be applied to TCP services, like max connections or syslog configurations.
• Regarding Host scoped configuration keys:
  • on v0.13, all Host scoped configuration keys are unsupported
  • on v0.14, auth-tls are supported

Every TCP service port creates a dedicated haproxy frontend that can be customized in three distinct ways:

• config-tcp-service in the global ConfigMap, this will add the same configurations to all the TCP service frontends
• config-tcp-service as an Ingress annotation, this will add the snippet in one TCP service
• config-proxy in the global ConfigMap using _front_tcp_<port-number> as the proxy name, see in the configuration snippet documentation how it works

See also:

• config-tcp-service configuration key
• tcp-service-log-format configuration key

Timeout

Define timeout configurations. The unit defaults to milliseconds if missing, change the unit with s, m, h, … suffix.

The following keys are supported:

• timeout-client: Maximum inactivity time on the client side
• timeout-client-fin: Maximum inactivity time on the client side for half-closed connections - FIN_WAIT state
• timeout-connect: Maximum time to wait for a connection to a backend
• timeout-http-request: Maximum time to wait for a complete HTTP request
• timeout-keep-alive: Maximum time to wait for a new HTTP request on keep-alive connections
• timeout-queue: Maximum time a connection should wait on a server queue before return a 503 error to the client
• timeout-server: Maximum inactivity time on the backend side
• timeout-server-fin: Maximum inactivity time on the backend side for half-closed connections - FIN_WAIT state
• timeout-stop: Maximum time to wait for long lived connections to finish, eg websocket, before hard-stop a HAProxy process due to a reload
• timeout-tunnel: Maximum inactivity time on the client and backend side for tunnels

See also:

• https://docs.haproxy.org/2.4/configuration.html#3.1-hard-stop-after (timeout-stop)
• https://docs.haproxy.org/2.4/configuration.html#2.4 (time suffix)

TLS ALPN

Defines the TLS ALPN extension advertisement. The default value is h2,http/1.1 which enables HTTP/2 on the client side.

tls-alpn was Global scope up to v0.10.

See also:

• https://docs.haproxy.org/2.4/configuration.html#5.1-alpn

Use HTX

Defines if the new HTX internal representation for HTTP elements should be used. The default value is true since v0.10, it was false on v0.9. HTX should be used to enable HTTP/2 protocol to backends.