Forum Discussion

wlopez's avatar
wlopez
Icon for Cirrocumulus rankCirrocumulus
Oct 22, 2020

iRule to close an established connection

I have tcp (not http) based service where client connections are permanent. By that I mean that once a connection to a pool member gets established its stays there 24x7. The pool has 2 pool membe...
application delivery
iRules
LTM
pool
Priority Group
tcp
Hamish's avatar
Hamish
Icon for Cirrocumulus rankCirrocumulus
Oct 22, 2020

LB_SELECTED is only going to fire when initially selecting a pool member. It won't fire after that.

 

There really isn't an event I can think of that will fire because a pool member came up/down if it's not associated with the connection itself (The iRule context is associated with a connection).

 

You could however run a timer... (Although it fails your 'as soon as' requirement unless you pool very often which will waste CPU). And ever X seconds check the availability of the pool hosts on the VS. If the connection is to a lower priority pool member than an available one, close the connection (Or if your protocol/app can handle it just connect to the newly available hi-priority pool member).

 

 

  • wlopez's avatar
    wlopez
    Icon for Cirrocumulus rankCirrocumulus
    Oct 22, 2020

    Thanks for your feedback.

    I'm not necessarily looking to do an instantaneous switch back to the higher priority member as soon as it becomes available..

    The main goal is to automatically close established connections to the lower priority pool member, so that the client platform is forced to reconnect and be sent back to the higher priority pool member within a reasonable amount of time (maybe up to a couple of minutes).

    I've never worked with timers.

    Would you happen to have an example you can share?