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prashanth
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Sep 09, 2020
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LTM Health Monitoring in HA

Hi There,

I have a doubt in F5 health monitoring on LTM HA pairs. Does the health monitoring done by only Active F5 and standby F5 sync the status of the Pool as Active F5 [OR] will it be done by both active and standby F5 separately on their Self IP and the pool status will be updated separately on both F5 independently.

 

As I have the cluster of LTM across two datacenter I have this concern before I failover, hence make sure the pool status remain the same after switch over.

 

Thanks in Advance

Prashanth

  • By design, BIG-IP systems in an HA pair (or larger Device Service Cluster) monitor and mark resource availability independently of one another. In other words, both the active and standby systems perform separate monitor tests, as defined within their configuration. Resource status is not synchronized between the systems. As a result, it is possible for one system to mark a resource, such as a pool member, as up in its configuration, while the other marks the same member as down in its configuration, as might be the case if the two systems use different routes to reach the pool member, and one of the routes is broken.

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  • By design, BIG-IP systems in an HA pair (or larger Device Service Cluster) monitor and mark resource availability independently of one another. In other words, both the active and standby systems perform separate monitor tests, as defined within their configuration. Resource status is not synchronized between the systems. As a result, it is possible for one system to mark a resource, such as a pool member, as up in its configuration, while the other marks the same member as down in its configuration, as might be the case if the two systems use different routes to reach the pool member, and one of the routes is broken.