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Forum Discussion

S_Meulmeester's avatar
S_Meulmeester
Icon for Cirrus rankCirrus
Aug 17, 2016

Force RST when when all pool members are down

Hello, I am testing a rather simple load balancing pool, and I want a TCP session (Syn) to be answered with a RST when all pool members are down config is standard protocol is tcp protocol profile client is tcp protocol profile server is use client profile no snat is used

 

When I now send a Syn packet, I get a Syn Ack and one second later Rst. I would like to get the RST immediatly.

 

I tested irules but this doesn't help

 

when LB_FAILED { if { [LB::server addr] eq "" } { reject } }

 

devops
LTM

1 Reply

  • jaikumar_f5's avatar
    jaikumar_f5
    Icon for Noctilucent rankNoctilucent
    Aug 17, 2016

    Did you take a look on this article.

     

    SOL9812

     

    Pools

     

    No available pool members.

     

    When all pool members are unavailable due to being disabled, forced offline, or down, the BIG-IP RST behavior varies slightly depending on the virtual server type. If the virtual server references a TCP profile (Standard virtual server type), the system allows the three-way TCP handshake to complete before sending the TCP RST to the client. If the virtual server references a FastL4 profile, the system sends a TCP RST packet in response to a connection attempt. The TCP RST packet is sent on the client side of the connection, and the source IP address of the reset is the relevant virtual server IP address.