ltm rule command ROUTE rttvar

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

ROUTE::rttvar
       Returns the cached round-trip-time variance (rttvar) estimate.

SYNOPSIS
       ROUTE::rttvar DESTINATION_IP_ADDRESS (GATEWAY_IP_ADDRESS)?

DESCRIPTION
       Returns the cached round-trip-time variance (rttvar) for the destination and/or gateway if the relevant TCP
       profile enables cmetrics-cache.

       The return value only applies to the TMM executing the command. It does not consider cache entries on other
       TMMs.

       ROUTE::rttvar returns a value of 0 when there are no statistics available.

       NOTE: The returned value is scaled to units of 100ns; to express it in the same units as TCP::rttvar multiply
       it by 16/10000.

       NOTE: When used with the fastL4 profile, RTT from client/server needs to be enabled and the client and server
       need to be using TCP timestamps.

       Syntax

       ROUTE::rttvar 

	    * The cached average variance in smoothed round-trip times for
	      connections to the given destination IP address.

       ROUTE::rttvar  

	    * The cached average variance in smoothed round-trip times for
	      connections to the given destination IP address reached through the
	      given gateway.

RETURN VALUE
VALID DURING
EXAMPLES
	when CLIENT_ACCEPTED {
	    log local0. "Cached rttvar is: [ROUTE::rttvar [IP::remote_addr]]"
	}

	when CLIENT_ACCEPTED {
	    set Gateway 10.3.1.11
	       # assume that $Gateway is the gateway address for [IP::remote_addr]
	    log local0. "Cached rttvar is: [ROUTE::rttvar [IP::remote_addr] $Gateway]"
	}

HINTS
SEE ALSO
CHANGE LOG
       @BIGIP-9.0.0 --First introduced the command.

BIG-IP						      2020-06-23					     iRule(1)