Mar 27, 2026 - For details about updated CVE-2025-53521 (BIG-IP APM vulnerability), refer to K000156741.

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zack_olson's avatar
zack_olson
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May 08, 2026

Traffic Policy forwarding behavior when pool is down

Hello folks.  Would someone be able to explain the behavior of a Traffic Policy when a pool is down.

 

For the scenario:

I want to create a single virtual server that hosts multiple websites. 

Each website is hosted on separate clusters of virtual machines.  The hosts in the cluster for example-1.com are in pool_example1, and the hosts in the cluster for example-2.com are in pool_example2.

I create a traffic policy that checks the HTTPS Host for the FQDN and then steers example-1.com to a pool_example1 and example-2.com to pool_example2.  I also create a rule to match all traffic with the action to reset the connection to catch everything else.  A default pool has been set on the Virtual Server. 

There is a health monitor in pool_example1 monitoring the nodes.  If all of the nodes in pool_example1 are down, and the health monitor marks it down, what would I expect to happen if I tried to navigate to example-1.com?  Is the traffic policy aware that the pool is down?  Would I get the default pool?  Or would I hit the catch all I built in the traffic policy and get a RST?  Or would something else happen?

 

Thanks!

 

1 Reply

  • Hello zack_olson​ 

    Policy will still send your request to pool_example1 and will be reseted cause there will be no healthy members.

    If you want to check pool active members before making a decision you should go with irules.

    There are plenty of examples online.