Forum Discussion

Baqar_Husain_81's avatar
Baqar_Husain_81
Icon for Nimbostratus rankNimbostratus
Jul 11, 2007

Prevent three way handshake on VIP when nodes unavailable

Very simple setup VIP and pool, if all nodes are unavailable (failed health check) we don't want the VIP to respond on a three-way handshake ... which it does by default due to the full-proxy feature of the big-ip.

 

 

Tech support advised an irule to discard the connection which made it worse:

 

when CLIENT_ACCEPTED {

 

if { [active_members VIP-vh9stage.nml.com_71.164_80] == 0 } {

 

discard

 

}

 

}

 

so i changed it to a reject which is better, but still doesn't prevent the 3-way. After all, it is when the client is accepted.

 

Thanks
application delivery
dev
devops
iRules
  • hoolio's avatar
    hoolio
    Icon for Cirrostratus rankCirrostratus
    Jul 12, 2007
    Oddly enough, when I tested on 9.4, I think 'discard' also triggered a reset (!?).

     

     

    I believe that when you add a TCP profile to a virtual server, there is no way to prevent TMM from completing a three way handshake.

     

     

    Check this post from rapmaster_c for more info (Click here).

     

     

    Aaron