WildFly Full 25 Model Reference

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  2. subsystem=undertow
  3. configuration=filter
  4. mod-cluster

A mod-cluster front end load balancer

Children (2)

  • affinity Determines how session affinity is handled. Typically used to enable ranked routing support or to disable routing completely.
    • none Web requests will not have an affinity for any particular server, routing information will be ignored. Intended for use cases where web session state is not maintained within the application server.
    • ranked Web requests will have an affinity for the first available node in a list typically comprised of: primary owner, backup nodes, local node (if not a primary nor backup owner).
    • single Web requests have an affinity for the member that last handled a given session. This option corresponds to traditional sticky session behavior.
  • balancer Runtime representation of a mod_cluster balancer

Provided capabilities(1)

Name Dynamic Other provider points
org.wildfly.undertow.mod_cluster-filter true

none

Attributes (28)

  • advertise-frequency The frequency (in milliseconds) that mod-cluster advertises itself on the network
    • Attribute Value
    Default Value 10000
    Type INT
    Nillable true
    Expressions Allowed true
    Unit MILLISECONDS
    Storage configuration
    Access Type read-write
    Restart Required all-services
  • advertise-path The path that mod-cluster is registered under.
    • Attribute Value
    Default Value /
    Type STRING
    Nillable true
    Expressions Allowed true
    Storage configuration
    Access Type read-write
    Restart Required all-services
  • advertise-protocol The protocol that is in use.
    • Attribute Value
    Default Value http
    Type STRING
    Nillable true
    Expressions Allowed true
    Storage configuration
    Access Type read-write
    Restart Required all-services
  • advertise-socket-binding The multicast group and port that is used to advertise.
    • Attribute Value
    Capability reference
    Type STRING
    Nillable true
    Expressions Allowed true
    Storage configuration
    Access Type read-write
    Restart Required all-services
  • broken-node-timeout The amount of time that must elapse before a broken node is removed from the table
    • Attribute Value
    Default Value 60000
    Type INT
    Nillable true
    Expressions Allowed true
    Unit MILLISECONDS
    Storage configuration
    Access Type read-write
    Restart Required all-services
  • cached-connections-per-thread The number of connections that will be kept alive indefinitely
    • Attribute Value
    Default Value 40
    Type INT
    Nillable true
    Expressions Allowed true
    Storage configuration
    Access Type read-write
    Restart Required all-services
  • connection-idle-timeout The amount of time a connection can be idle before it will be closed. Connections will not time out once the pool size is down to the configured minimum (as configured by cached-connections-per-thread)
    • Attribute Value
    Default Value 60
    Type INT
    Nillable true
    Expressions Allowed true
    Unit SECONDS
    Storage configuration
    Access Type read-write
    Restart Required all-services
  • connections-per-thread The number of connections that will be maintained to backend servers, per IO thread.
    • Attribute Value
    Default Value 40
    Type INT
    Nillable true
    Expressions Allowed true
    Storage configuration
    Access Type read-write
    Restart Required all-services
  • enable-http2 If the load balancer should attempt to upgrade back end connections to HTTP2. If HTTP2 is not supported HTTP or HTTPS will be used as normal
    • Attribute Value
    Default Value false
    Type BOOLEAN
    Nillable true
    Expressions Allowed false
    Storage configuration
    Access Type read-write
    Restart Required all-services
  • failover-strategy Determines how a failover node is chosen, in the event that the node to which a session has affinity is not available.
    • Attribute Value
    Default Value LOAD_BALANCED
    Type STRING
    Nillable true
    Expressions Allowed false
    Storage configuration
    Access Type read-write
    Restart Required all-services
    Allowed Values LOAD_BALANCED
    DETERMINISTIC
  • health-check-interval The frequency of health check pings to backend nodes
    • Attribute Value
    Default Value 10000
    Type INT
    Nillable true
    Expressions Allowed true
    Unit MILLISECONDS
    Storage configuration
    Access Type read-write
    Restart Required all-services
  • http2-enable-push If push should be enabled for HTTP/2 connections
    • Attribute Value
    Default Value true
    Type BOOLEAN
    Nillable true
    Expressions Allowed true
    Storage configuration
    Access Type read-write
    Restart Required all-services
  • http2-header-table-size The size of the header table used for HPACK compression, in bytes. This amount of memory will be allocated per connection for compression. Larger values use more memory but may give better compression.
    • Attribute Value
    Default Value 4096
    Type INT
    Nillable true
    Expressions Allowed true
    Min 1
    Max 2,147,483,647
    Unit BYTES
    Storage configuration
    Access Type read-write
    Restart Required all-services
  • http2-initial-window-size The flow control window size that controls how quickly the client can send data to the server
    • Attribute Value
    Default Value 65535
    Type INT
    Nillable true
    Expressions Allowed true
    Min 1
    Max 2,147,483,647
    Unit BYTES
    Storage configuration
    Access Type read-write
    Restart Required all-services
  • http2-max-concurrent-streams The maximum number of HTTP/2 streams that can be active at any time on a single connection
    • Attribute Value
    Type INT
    Nillable true
    Expressions Allowed true
    Min 1
    Max 2,147,483,647
    Storage configuration
    Access Type read-write
    Restart Required all-services
  • http2-max-frame-size The max HTTP/2 frame size
    • Attribute Value
    Default Value 16384
    Type INT
    Nillable true
    Expressions Allowed true
    Min 1
    Max 2,147,483,647
    Unit BYTES
    Storage configuration
    Access Type read-write
    Restart Required all-services
  • http2-max-header-list-size The maximum size of request headers the server is prepared to accept
    • Attribute Value
    Type INT
    Nillable true
    Expressions Allowed true
    Min 1
    Max 2,147,483,647
    Unit BYTES
    Storage configuration
    Access Type read-write
    Restart Required all-services
  • management-access-predicate A predicate that is applied to incoming requests to determine if they can perform mod cluster management commands. Provides additional security on top of what is provided by limiting management to requests that originate from the management-socket-binding
    • Attribute Value
    Type STRING
    Nillable true
    Expressions Allowed true
    Storage configuration
    Access Type read-write
    Restart Required all-services
  • management-socket-binding The socket binding of the mod_cluster management address and port. When using mod_cluster two HTTP listeners should be defined, a public one to handle requests, and one bound to the internal network to handle mod cluster commands. This socket binding should correspond to the internal listener, and should not be publicly accessible.
    • Attribute Value
    Capability reference
    Type STRING
    Nillable false
    Expressions Allowed true
    Storage configuration
    Access Type read-write
    Restart Required all-services
  • max-ajp-packet-size The maximum size for AJP packets. Increasing this will allow AJP to work for requests/responses that have a large amount of headers. This is an advanced option, and must be the same between load balancers and backend servers.
    • Attribute Value
    Default Value 8192
    Type INT
    Nillable true
    Expressions Allowed true
    Min 1
    Max 2,147,483,647
    Unit BYTES
    Storage configuration
    Access Type read-write
    Restart Required all-services
  • max-request-time The max amount of time that a request to a backend node can take before it is killed
    • Attribute Value
    Default Value -1
    Type INT
    Nillable true
    Expressions Allowed true
    Unit MILLISECONDS
    Storage configuration
    Access Type read-write
    Restart Required all-services
  • max-retries The number of times to attempt to retry a request if it fails. Note that if a request is not considered idempotent then it will only be retried if the proxy can be sure it was not sent to the backend server).
    • Attribute Value
    Default Value 1
    Type INT
    Nillable true
    Expressions Allowed true
    Storage configuration
    Access Type read-write
    Restart Required all-services
  • request-queue-size The number of requests that can be queued if the connection pool is full before requests are rejected with a 503
    • Attribute Value
    Default Value 1000
    Type INT
    Nillable true
    Expressions Allowed true
    Storage configuration
    Access Type read-write
    Restart Required all-services
  • security-key The security key that is used for the mod-cluster group. All members must use the same security key.
    • Attribute Value
    Type STRING
    Nillable true
    Expressions Allowed true
    Storage configuration
    Access Type read-write
    Restart Required all-services
  • security-realm The security realm that provides the SSL configuration
    • Deprecated Since 4.0.0
    Use the ssl-context attribute to reference a configured SSLContext directly.
    Attribute Value
    Type STRING
    Nillable true
    Expressions Allowed false
    Storage configuration
    Access Type read-write
    Restart Required all-services
  • ssl-context Reference to the SSLContext to be used by this filter.
    • Attribute Value
    Capability reference
    Type STRING
    Nillable true
    Expressions Allowed false
    Storage configuration
    Access Type read-write
    Restart Required all-services
  • use-alias If an alias check is performed
    • Attribute Value
    Default Value false
    Type BOOLEAN
    Nillable true
    Expressions Allowed false
    Storage configuration
    Access Type read-write
    Restart Required all-services
  • worker The XNIO worker that is used to send the advertise notifications
    • Attribute Value
    Default Value default
    Capability reference
    Type STRING
    Nillable true
    Expressions Allowed true
    Storage configuration
    Access Type read-write
    Restart Required all-services

Operations (2)

  • add Adds a front end mod-proxy load balancer
    Request Parameter Type Required Expressions Allowed Default value Description
    management-socket-binding STRING true true The socket binding of the mod_cluster management address and port. When using mod_cluster two HTTP listeners should be defined, a public one to handle requests, and one bound to the internal network to handle mod cluster commands. This socket binding should correspond to the internal listener, and should not be publicly accessible.
    advertise-socket-binding STRING false true The multicast group and port that is used to advertise.
    security-key STRING false true The security key that is used for the mod-cluster group. All members must use the same security key.
    advertise-protocol STRING false true http The protocol that is in use.
    advertise-path STRING false true / The path that mod-cluster is registered under.
    advertise-frequency INT false true 10000 The frequency (in milliseconds) that mod-cluster advertises itself on the network
    failover-strategy STRING false false LOAD_BALANCED Determines how a failover node is chosen, in the event that the node to which a session has affinity is not available.
    health-check-interval INT false true 10000 The frequency of health check pings to backend nodes
    broken-node-timeout INT false true 60000 The amount of time that must elapse before a broken node is removed from the table
    worker STRING false true default The XNIO worker that is used to send the advertise notifications
    max-request-time INT false true -1 The max amount of time that a request to a backend node can take before it is killed
    management-access-predicate STRING false true A predicate that is applied to incoming requests to determine if they can perform mod cluster management commands. Provides additional security on top of what is provided by limiting management to requests that originate from the management-socket-binding
    connections-per-thread INT false true 40 The number of connections that will be maintained to backend servers, per IO thread.
    cached-connections-per-thread INT false true 40 The number of connections that will be kept alive indefinitely
    connection-idle-timeout INT false true 60 The amount of time a connection can be idle before it will be closed. Connections will not time out once the pool size is down to the configured minimum (as configured by cached-connections-per-thread)
    request-queue-size INT false true 1000 The number of requests that can be queued if the connection pool is full before requests are rejected with a 503
    security-realm STRING false false The security realm that provides the SSL configuration
    ssl-context STRING false false Reference to the SSLContext to be used by this filter.
    use-alias BOOLEAN false false false If an alias check is performed
    enable-http2 BOOLEAN false false false If the load balancer should attempt to upgrade back end connections to HTTP2. If HTTP2 is not supported HTTP or HTTPS will be used as normal
    max-ajp-packet-size INT false true 8192 The maximum size for AJP packets. Increasing this will allow AJP to work for requests/responses that have a large amount of headers. This is an advanced option, and must be the same between load balancers and backend servers.
    http2-max-header-list-size INT false true The maximum size of request headers the server is prepared to accept
    http2-max-frame-size INT false true 16384 The max HTTP/2 frame size
    http2-max-concurrent-streams INT false true The maximum number of HTTP/2 streams that can be active at any time on a single connection
    http2-initial-window-size INT false true 65535 The flow control window size that controls how quickly the client can send data to the server
    http2-header-table-size INT false true 4096 The size of the header table used for HPACK compression, in bytes. This amount of memory will be allocated per connection for compression. Larger values use more memory but may give better compression.
    http2-enable-push BOOLEAN false true true If push should be enabled for HTTP/2 connections
    max-retries INT false true 1 The number of times to attempt to retry a request if it fails. Note that if a request is not considered idempotent then it will only be retried if the proxy can be sure it was not sent to the backend server).
  • remove Removes a mod cluster proxy handler