# kube-apiserver Configuration (v1alpha1)

kube-apiserver Configuration (v1alpha1)Package v1alpha1 is the v1alpha1 version of the API.Resource TypesAdmissionConfigurationAuthenticationConfigurationAuthorizationConfigurationEgressSelectorConfigurationTracingConfigurationTracingConfigurationAppears in:KubeletConfigurationTracingConfigurationTracingConfiguration provides versioned configuration for OpenTelemetry tracing clients.FieldDescriptionendpointstringEndpoint of the collector this component will report traces to. The connection is insecure, and does not currently support TLS. Recommended is unset, and endpoint is the otlp grpc default, localhost:4317.samplingRatePerMillionint32SamplingRatePerMillion is the number of samples to collect per million spans. Recommended is unset. If unset, sampler respects its parent span's sampling rate, but otherwise never samples.AdmissionConfigurationAdmissionConfiguration provides versioned configuration for admission controllers.FieldDescriptionapiVersionstringapiserver.k8s.io/v1alpha1kindstringAdmissionConfigurationplugins[]AdmissionPluginConfigurationPlugins allows specifying a configuration per admission control plugin.AuthenticationConfigurationAuthenticationConfiguration provides versioned configuration for authentication.FieldDescriptionapiVersionstringapiserver.k8s.io/v1alpha1kindstringAuthenticationConfigurationjwt [Required][]JWTAuthenticatorjwt is a list of authenticator to authenticate Kubernetes users using JWT compliant tokens. The authenticator will attempt to parse a raw ID token, verify it's been signed by the configured issuer. The public key to verify the signature is discovered from the issuer's public endpoint using OIDC discovery. For an incoming token, each JWT authenticator will be attempted in the order in which it is specified in this list. Note however that other authenticators may run before or after the JWT authenticators. The specific position of JWT authenticators in relation to other authenticators is neither defined nor stable across releases. Since each JWT authenticator must have a unique issuer URL, at most one JWT authenticator will attempt to cryptographically validate the token.The minimum valid JWT payload must contain the following claims: { "iss": "https://issuer.example.com", "aud": ["audience"], "exp": 1234567890, "": "username" }anonymous [Required]AnonymousAuthConfigIf present --anonymous-auth must not be setAuthorizationConfigurationFieldDescriptionapiVersionstringapiserver.k8s.io/v1alpha1kindstringAuthorizationConfigurationauthorizers [Required][]AuthorizerConfigurationAuthorizers is an ordered list of authorizers to authorize requests against. This is similar to the --authorization-modes kube-apiserver flag Must be at least one.EgressSelectorConfigurationEgressSelectorConfiguration provides versioned configuration for egress selector clients.FieldDescriptionapiVersionstringapiserver.k8s.io/v1alpha1kindstringEgressSelectorConfigurationegressSelections [Required][]EgressSelectionconnectionServices contains a list of egress selection client configurationsTracingConfigurationTracingConfiguration provides versioned configuration for tracing clients.FieldDescriptionapiVersionstringapiserver.k8s.io/v1alpha1kindstringTracingConfigurationTracingConfiguration [Required]TracingConfiguration(Members of TracingConfiguration are embedded into this type.)Embed the component config tracing configuration structAdmissionPluginConfigurationAppears in:AdmissionConfigurationAdmissionPluginConfiguration provides the configuration for a single plug-in.FieldDescriptionname [Required]stringName is the name of the admission controller. It must match the registered admission plugin name.pathstringPath is the path to a configuration file that contains the plugin's configurationconfigurationk8s.io/apimachinery/pkg/runtime.UnknownConfiguration is an embedded configuration object to be used as the plugin's configuration. If present, it will be used instead of the path to the configuration file.AnonymousAuthConditionAppears in:AnonymousAuthConfigAnonymousAuthCondition describes the condition under which anonymous auth should be enabled.FieldDescriptionpath [Required]stringPath for which anonymous auth is enabled.AnonymousAuthConfigAppears in:AuthenticationConfigurationAnonymousAuthConfig provides the configuration for the anonymous authenticator.FieldDescriptionenabled [Required]boolNo description provided.conditions [Required][]AnonymousAuthConditionIf set, anonymous auth is only allowed if the request meets one of the conditions.AudienceMatchPolicyType(Alias of string)Appears in:IssuerAudienceMatchPolicyType is a set of valid values for issuer.audienceMatchPolicyAuthorizerConfigurationAppears in:AuthorizationConfigurationFieldDescriptiontype [Required]stringType refers to the type of the authorizer "Webhook" is supported in the generic API server Other API servers may support additional authorizer types like Node, RBAC, ABAC, etc.name [Required]stringName used to describe the webhook This is explicitly used in monitoring machinery for metrics Note: Names must be DNS1123 labels like myauthorizername or subdomains like myauthorizer.example.domain Required, with no defaultwebhook [Required]WebhookConfigurationWebhook defines the configuration for a Webhook authorizer Must be defined when Type=Webhook Must not be defined when Type!=WebhookClaimMappingsAppears in:JWTAuthenticatorClaimMappings provides the configuration for claim mappingFieldDescriptionusername [Required]PrefixedClaimOrExpressionusername represents an option for the username attribute. The claim's value must be a singular string. Same as the --oidc-username-claim and --oidc-username-prefix flags. If username.expression is set, the expression must produce a string value. If username.expression uses 'claims.email', then 'claims.email_verified' must be used in username.expression or extra[*].valueExpression or claimValidationRules[<*>].expression. An example claim validation rule expression that matches the validation automatically applied when username.claim is set to 'email' is 'claims.?email_verified.orValue(true) == true'. By explicitly comparing the value to true, we let type-checking see the result will be a boolean, and to make sure a non-boolean email_verified claim will be caught at runtime.In the flag based approach, the --oidc-username-claim and --oidc-username-prefix are optional. If --oidc-username-claim is not set, the default value is "sub". For the authentication config, there is no defaulting for claim or prefix. The claim and prefix must be set explicitly. For claim, if --oidc-username-claim was not set with legacy flag approach, configure username.claim="sub" in the authentication config. For prefix: (1) --oidc-username-prefix="-", no prefix was added to the username. For the same behavior using authentication config, set username.prefix="" (2) --oidc-username-prefix="" and --oidc-username-claim != "email", prefix was "<value of --oidc-issuer-url>#". For the same behavior using authentication config, set username.prefix="#" (3) --oidc-username-prefix="". For the same behavior using authentication config, set username.prefix=""groupsPrefixedClaimOrExpressiongroups represents an option for the groups attribute. The claim's value must be a string or string array claim. If groups.claim is set, the prefix must be specified (and can be the empty string). If groups.expression is set, the expression must produce a string or string array value. "", [], and null values are treated as the group mapping not being present.uidClaimOrExpressionuid represents an option for the uid attribute. Claim must be a singular string claim. If uid.expression is set, the expression must produce a string value.extra[]ExtraMappingextra represents an option for the extra attribute. expression must produce a string or string array value. If the value is empty, the extra mapping will not be present.hard-coded extra key/valuekey: "foo" valueExpression: "'bar'" This will result in an extra attribute - foo: ["bar"]hard-coded key, value copying claim valuekey: "foo" valueExpression: "claims.some_claim" This will result in an extra attribute - foo: [value of some_claim]hard-coded key, value derived from claim valuekey: "admin" valueExpression: '(has(claims.is_admin) && claims.is_admin) ? "true":""' This will result in:if is_admin claim is present and true, extra attribute - admin: ["true"]if is_admin claim is present and false or is_admin claim is not present, no extra attribute will be addedClaimOrExpressionAppears in:ClaimMappingsClaimOrExpression provides the configuration for a single claim or expression.FieldDescriptionclaimstringclaim is the JWT claim to use. Either claim or expression must be set. Mutually exclusive with expression.expressionstringexpression represents the expression which will be evaluated by CEL.CEL expressions have access to the contents of the token claims, organized into CEL variable:'claims' is a map of claim names to claim values. For example, a variable named 'sub' can be accessed as 'claims.sub'. Nested claims can be accessed using dot notation, e.g. 'claims.foo.bar'.Documentation on CEL: https://kubernetes.io/docs/reference/using-api/cel/Mutually exclusive with claim.ClaimValidationRuleAppears in:JWTAuthenticatorClaimValidationRule provides the configuration for a single claim validation rule.FieldDescriptionclaimstringclaim is the name of a required claim. Same as --oidc-required-claim flag. Only string claim keys are supported. Mutually exclusive with expression and message.requiredValuestringrequiredValue is the value of a required claim. Same as --oidc-required-claim flag. Only string claim values are supported. If claim is set and requiredValue is not set, the claim must be present with a value set to the empty string. Mutually exclusive with expression and message.expressionstringexpression represents the expression which will be evaluated by CEL. Must produce a boolean.CEL expressions have access to the contents of the token claims, organized into CEL variable:'claims' is a map of claim names to claim values. For example, a variable named 'sub' can be accessed as 'claims.sub'. Nested claims can be accessed using dot notation, e.g. 'claims.foo.bar'. Must return true for the validation to pass.Documentation on CEL: https://kubernetes.io/docs/reference/using-api/cel/Mutually exclusive with claim and requiredValue.messagestringmessage customizes the returned error message when expression returns false. message is a literal string. Mutually exclusive with claim and requiredValue.ConnectionAppears in:EgressSelectionConnection provides the configuration for a single egress selection client.FieldDescriptionproxyProtocol [Required]ProtocolTypeProtocol is the protocol used to connect from client to the konnectivity server.transportTransportTransport defines the transport configurations we use to dial to the konnectivity server. This is required if ProxyProtocol is HTTPConnect or GRPC.EgressSelectionAppears in:EgressSelectorConfigurationEgressSelection provides the configuration for a single egress selection client.FieldDescriptionname [Required]stringname is the name of the egress selection. Currently supported values are "controlplane", "master", "etcd" and "cluster" The "master" egress selector is deprecated in favor of "controlplane"connection [Required]Connectionconnection is the exact information used to configure the egress selectionExtraMappingAppears in:ClaimMappingsExtraMapping provides the configuration for a single extra mapping.FieldDescriptionkey [Required]stringkey is a string to use as the extra attribute key. key must be a domain-prefix path (e.g. example.org/foo). All characters before the first "/" must be a valid subdomain as defined by RFC 1123. All characters trailing the first "/" must be valid HTTP Path characters as defined by RFC 3986. key must be lowercase. Required to be unique.valueExpression [Required]stringvalueExpression is a CEL expression to extract extra attribute value. valueExpression must produce a string or string array value. "", [], and null values are treated as the extra mapping not being present. Empty string values contained within a string array are filtered out.CEL expressions have access to the contents of the token claims, organized into CEL variable:'claims' is a map of claim names to claim values. For example, a variable named 'sub' can be accessed as 'claims.sub'. Nested claims can be accessed using dot notation, e.g. 'claims.foo.bar'.Documentation on CEL: https://kubernetes.io/docs/reference/using-api/cel/IssuerAppears in:JWTAuthenticatorIssuer provides the configuration for an external provider's specific settings.FieldDescriptionurl [Required]stringurl points to the issuer URL in a format https://url or https://url/path. This must match the "iss" claim in the presented JWT, and the issuer returned from discovery. Same value as the --oidc-issuer-url flag. Discovery information is fetched from "{url}/.well-known/openid-configuration" unless overridden by discoveryURL. Required to be unique across all JWT authenticators. Note that egress selection configuration is not used for this network connection.discoveryURLstringdiscoveryURL, if specified, overrides the URL used to fetch discovery information instead of using "{url}/.well-known/openid-configuration". The exact value specified is used, so "/.well-known/openid-configuration" must be included in discoveryURL if needed.The "issuer" field in the fetched discovery information must match the "issuer.url" field in the AuthenticationConfiguration and will be used to validate the "iss" claim in the presented JWT. This is for scenarios where the well-known and jwks endpoints are hosted at a different location than the issuer (such as locally in the cluster).Example: A discovery url that is exposed using kubernetes service 'oidc' in namespace 'oidc-namespace' and discovery information is available at '/.well-known/openid-configuration'. discoveryURL: "https://oidc.oidc-namespace/.well-known/openid-configuration" certificateAuthority is used to verify the TLS connection and the hostname on the leaf certificate must be set to 'oidc.oidc-namespace'.curl https://oidc.oidc-namespace/.well-known/openid-configuration (.discoveryURL field) { issuer: "https://oidc.example.com" (.url field) }discoveryURL must be different from url. Required to be unique across all JWT authenticators. Note that egress selection configuration is not used for this network connection.certificateAuthoritystringcertificateAuthority contains PEM-encoded certificate authority certificates used to validate the connection when fetching discovery information. If unset, the system verifier is used. Same value as the content of the file referenced by the --oidc-ca-file flag.audiences [Required][]stringaudiences is the set of acceptable audiences the JWT must be issued to. At least one of the entries must match the "aud" claim in presented JWTs. Same value as the --oidc-client-id flag (though this field supports an array). Required to be non-empty.audienceMatchPolicyAudienceMatchPolicyTypeaudienceMatchPolicy defines how the "audiences" field is used to match the "aud" claim in the presented JWT. Allowed values are:"MatchAny" when multiple audiences are specified andempty (or unset) or "MatchAny" when a single audience is specified.MatchAny: the "aud" claim in the presented JWT must match at least one of the entries in the "audiences" field. For example, if "audiences" is ["foo", "bar"], the "aud" claim in the presented JWT must contain either "foo" or "bar" (and may contain both)."": The match policy can be empty (or unset) when a single audience is specified in the "audiences" field. The "aud" claim in the presented JWT must contain the single audience (and may contain others).For more nuanced audience validation, use claimValidationRules. example: claimValidationRule[].expression: 'sets.equivalent(claims.aud, ["bar", "foo", "baz"])' to require an exact match.JWTAuthenticatorAppears in:AuthenticationConfigurationJWTAuthenticator provides the configuration for a single JWT authenticator.FieldDescriptionissuer [Required]Issuerissuer contains the basic OIDC provider connection options.claimValidationRules[]ClaimValidationRuleclaimValidationRules are rules that are applied to validate token claims to authenticate users.claimMappings [Required]ClaimMappingsclaimMappings points claims of a token to be treated as user attributes.userValidationRules[]UserValidationRuleuserValidationRules are rules that are applied to final user before completing authentication. These allow invariants to be applied to incoming identities such as preventing the use of the system: prefix that is commonly used by Kubernetes components. The validation rules are logically ANDed together and must all return true for the validation to pass.PrefixedClaimOrExpressionAppears in:ClaimMappingsPrefixedClaimOrExpression provides the configuration for a single prefixed claim or expression.FieldDescriptionclaimstringclaim is the JWT claim to use. Mutually exclusive with expression.prefixstringprefix is prepended to claim's value to prevent clashes with existing names. prefix needs to be set if claim is set and can be the empty string. Mutually exclusive with expression.expressionstringexpression represents the expression which will be evaluated by CEL.CEL expressions have access to the contents of the token claims, organized into CEL variable:'claims' is a map of claim names to claim values. For example, a variable named 'sub' can be accessed as 'claims.sub'. Nested claims can be accessed using dot notation, e.g. 'claims.foo.bar'.Documentation on CEL: https://kubernetes.io/docs/reference/using-api/cel/Mutually exclusive with claim and prefix.ProtocolType(Alias of string)Appears in:ConnectionProtocolType is a set of valid values for Connection.ProtocolTypeTCPTransportAppears in:TransportTCPTransport provides the information to connect to konnectivity server via TCPFieldDescriptionurl [Required]stringURL is the location of the konnectivity server to connect to. As an example it might be "https://127.0.0.1:8131"tlsConfigTLSConfigTLSConfig is the config needed to use TLS when connecting to konnectivity serverTLSConfigAppears in:TCPTransportTLSConfig provides the authentication information to connect to konnectivity server Only used with TCPTransportFieldDescriptioncaBundlestringcaBundle is the file location of the CA to be used to determine trust with the konnectivity server. Must be absent/empty if TCPTransport.URL is prefixed with http:// If absent while TCPTransport.URL is prefixed with https://, default to system trust roots.clientKeystringclientKey is the file location of the client key to be used in mtls handshakes with the konnectivity server. Must be absent/empty if TCPTransport.URL is prefixed with http:// Must be configured if TCPTransport.URL is prefixed with https://clientCertstringclientCert is the file location of the client certificate to be used in mtls handshakes with the konnectivity server. Must be absent/empty if TCPTransport.URL is prefixed with http:// Must be configured if TCPTransport.URL is prefixed with https://TransportAppears in:ConnectionTransport defines the transport configurations we use to dial to the konnectivity serverFieldDescriptiontcpTCPTransportTCP is the TCP configuration for communicating with the konnectivity server via TCP ProxyProtocol of GRPC is not supported with TCP transport at the moment Requires at least one of TCP or UDS to be setudsUDSTransportUDS is the UDS configuration for communicating with the konnectivity server via UDS Requires at least one of TCP or UDS to be setUDSTransportAppears in:TransportUDSTransport provides the information to connect to konnectivity server via UDSFieldDescriptionudsName [Required]stringUDSName is the name of the unix domain socket to connect to konnectivity server This does not use a unix:// prefix. (Eg: /etc/srv/kubernetes/konnectivity-server/konnectivity-server.socket)UserValidationRuleAppears in:JWTAuthenticatorUserValidationRule provides the configuration for a single user info validation rule.FieldDescriptionexpression [Required]stringexpression represents the expression which will be evaluated by CEL. Must return true for the validation to pass.CEL expressions have access to the contents of UserInfo, organized into CEL variable:'user' - authentication.k8s.io/v1, Kind=UserInfo object Refer to https://github.com/kubernetes/api/blob/release-1.28/authentication/v1/types.go#L105-L122 for the definition. API documentation: https://kubernetes.io/docs/reference/generated/kubernetes-api/v1.28/#userinfo-v1-authentication-k8s-ioDocumentation on CEL: https://kubernetes.io/docs/reference/using-api/cel/messagestringmessage customizes the returned error message when rule returns false. message is a literal string.WebhookConfigurationAppears in:AuthorizerConfigurationFieldDescriptionauthorizedTTL [Required]meta/v1.DurationThe duration to cache 'authorized' responses from the webhook authorizer. Same as setting --authorization-webhook-cache-authorized-ttl flag Default: 5m0sunauthorizedTTL [Required]meta/v1.DurationThe duration to cache 'unauthorized' responses from the webhook authorizer. Same as setting --authorization-webhook-cache-unauthorized-ttl flag Default: 30stimeout [Required]meta/v1.DurationTimeout for the webhook request Maximum allowed value is 30s. Required, no default value.subjectAccessReviewVersion [Required]stringThe API version of the authorization.k8s.io SubjectAccessReview to send to and expect from the webhook. Same as setting --authorization-webhook-version flag Valid values: v1beta1, v1 Required, no default valuematchConditionSubjectAccessReviewVersion [Required]stringMatchConditionSubjectAccessReviewVersion specifies the SubjectAccessReview version the CEL expressions are evaluated against Valid values: v1 Required, no default valuefailurePolicy [Required]stringControls the authorization decision when a webhook request fails to complete or returns a malformed response or errors evaluating matchConditions. Valid values:NoOpinion: continue to subsequent authorizers to see if one of them allows the requestDeny: reject the request without consulting subsequent authorizers Required, with no default.connectionInfo [Required]WebhookConnectionInfoConnectionInfo defines how we talk to the webhookmatchConditions [Required][]WebhookMatchConditionmatchConditions is a list of conditions that must be met for a request to be sent to this webhook. An empty list of matchConditions matches all requests. There are a maximum of 64 match conditions allowed.The exact matching logic is (in order):If at least one matchCondition evaluates to FALSE, then the webhook is skipped.If ALL matchConditions evaluate to TRUE, then the webhook is called.If at least one matchCondition evaluates to an error (but none are FALSE):If failurePolicy=Deny, then the webhook rejects the requestIf failurePolicy=NoOpinion, then the error is ignored and the webhook is skippedWebhookConnectionInfoAppears in:WebhookConfigurationFieldDescriptiontype [Required]stringControls how the webhook should communicate with the server. Valid values:KubeConfigFile: use the file specified in kubeConfigFile to locate the server.InClusterConfig: use the in-cluster configuration to call the SubjectAccessReview API hosted by kube-apiserver. This mode is not allowed for kube-apiserver.kubeConfigFile [Required]stringPath to KubeConfigFile for connection info Required, if connectionInfo.Type is KubeConfigWebhookMatchConditionAppears in:WebhookConfigurationFieldDescriptionexpression [Required]stringexpression represents the expression which will be evaluated by CEL. Must evaluate to bool. CEL expressions have access to the contents of the SubjectAccessReview in v1 version. If version specified by subjectAccessReviewVersion in the request variable is v1beta1, the contents would be converted to the v1 version before evaluating the CEL expression.'resourceAttributes' describes information for a resource access request and is unset for non-resource requests. e.g. has(request.resourceAttributes) && request.resourceAttributes.namespace == 'default''nonResourceAttributes' describes information for a non-resource access request and is unset for resource requests. e.g. has(request.nonResourceAttributes) && request.nonResourceAttributes.path == '/healthz'.'user' is the user to test for. e.g. request.user == 'alice''groups' is the groups to test for. e.g. ('group1' in request.groups)'extra' corresponds to the user.Info.GetExtra() method from the authenticator.'uid' is the information about the requesting user. e.g. request.uid == '1'Documentation on CEL: https://kubernetes.io/docs/reference/using-api/cel/This page is automatically generated.If you plan to report an issue with this page, mention that the page is auto-generated in your issue description. The fix may need to happen elsewhere in the Kubernetes project.