ltm rule command XLAT listen

iRule(1)						BIG-IP TMSH Manual						  iRule(1)

XLAT::listen
       Creates a related ephemeral listener.

SYNOPSIS
       XLAT::listen (-hairpin)? (-inherit-main-rules)? (-single-connection)? (-translation-loose)? (XLAT_LISTEN_SUBCMDS)+

DESCRIPTION
       Creates a related ephemeral listener and returns the TCL handle for the listener. bind address and port can be omitted. It
       is recommend that users don't set this, so the command can choose an IP:port based on the server address specified and also
       conforms to source translation config. If the server address is on the clientside, then bind IP::port will be a valid
       endpoint on the clientside and conforms to the source translation config on the clientside. If the sever address is on the
       serverside, then bind IP::port will be a valid endpoint on the serverside and conforms to the source translation on config
       serverside, if any.  When configured source translation is LSN or SECURITY-DYNAMIC-PAT, a reserved endpoint is also created
       for bind address:port. If user has already created a reserved endpoint (using XLAT::src_endpoint_reservation), then it will
       be reused provided the allow address:port match the client address:port used to reserve the endpoint.

       Syntax: XLAT::listen [-hairpin] [-inherit-main-rules] [-single-connection] [-translation-loose]  { [proto
       ] bind -allow|-deny  [-ip ] [-port ] server   [allow  []]
       [inherit-vs ] }

       Sets up a related ephemeral listener to allow an incoming related connection to be established: + -hairpin: This listener
       will be used for accepting hairpin connections only. This option is supported with LSN and SECURITY-DYNAMIC-PAT source
       translation config only. This option should be used when hairpin connections from other subscribers using LSN or SECURITY-
       DYNAMIC-PAT are anticipated, as such the incoming subscriber flow (does not have to be the same as listener subscriber)
       must match an existing virtual-server with a LSN or SECURITY-DYNAMIC-PAT source translation pool attached.  +
       -inherit-main-rules: The created listener executes the main rules(tmsh list ltm virtual  rules) attached to parent
       virtual. Related rules are executed by default(tmsh list ltm virtual  related-rules) + -single-connection: Listener
       expires after one connection is received.  + -translation-loose: The command will try to use the hint data(-ip and/or
       -port) provided. Command will not fail if the provided hints cannot be used.  + lifetime: The number of seconds to hold the
       listener open waiting on a connection, parameter is required.  + proto: Set the protocol that the listener should listen
       for. If not specified this is determined using the parent connection.  + bind: vlan/ifc list, addr, port to listen on.
       -allow/-deny determine if the vlan list is an allow or a deny list. "*" can be used to denote all vlans. For hairpin
       connections a separate listener must be created. Just enabling the listener on all VLANS will not work for hairpinning.	+
       server: The address and port to connect the listening connection to.  + allow: The address and optional port to restrict
       the incoming connection to.  + inherit-vs: inherit the profiles, irules, and protocol of the provided virtual server.

RETURN VALUE
       Return the TCL handle to the created listener. String representaion of the handle: "%,,%,,%,,,". Route domain is not printed when zero.

VALID DURING
       SERVER_CONNECTED, CLIENT_DATA, SERVER_DATA

EXAMPLES
	when SERVER_CONNECTED {
	    set listen [XLAT::listen -inherit-main-rules 30 {
		proto [IP::protocol]
		bind -allow [LINK::vlan_id],/Common/public1 -ip [serverside {IP::local_addr}]
		server [IP::client_addr] 7000
		allow [LB::server addr] 0
		inherit-vs [virtual]
	    }]
	    log local0. "LISTEN: $listen"

	    # hairpin
	    set listen_hairpin [XLAT::listen -hairpin 30 {
		proto [IP::protocol]
		bind -allow [clientside {LINK::vlan_id}]
		server [IP::client_addr] 7000
	    }]
	}

HINTS
SEE ALSO
CHANGE LOG
       @BIGIP-14.1.0 --First introduced the command.

BIG-IP							    2022-04-12							  iRule(1)