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

Forum Discussion

jamesdris's avatar
jamesdris
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Mar 19, 2019

F5 DNS sync groups, datacenters and prober pools

I have a few questions - 1 - Can we have prober pools in a global availability mode? If yes does it mean when the primary listener is down the servers will be polled using the secondary prober on th...
application delivery
BIG-IP DNS
f5 dns sync group
prober pool
Rico_368208's avatar
Rico_368208
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Mar 19, 2019
  1. Yes, global availability can be configured and it just means it will use the first available member of the pool. You can see that in the Create a Prober Pool section of this article
  2. If no prober pool is configured, the BIG-IP DNS devices negotiate amongst themselves which DNS device is responsible for which server.
  3. If there is a discrepancy in DNS devices marking a device as up, it will choose the health monitor data from the BIG-IP DNS device assigned to that server.

If you have any more questions, I am sure I can help

 

jamesdris's avatar
jamesdris
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Mar 20, 2019

so, imagine GTM1 is in DC1 and GTM2 is in DC2, and server1 is assigned GTM1 as a prober. If GTM1 marks server1 up while GTM2 marks it down will the server in effect be marked up or down?

 

also, what would happen if GTM1 is not able to reach the server1(but GTM1 is actually online) and marks it down while communication between GTM1 and GTM2 works well?