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hunghsingchin's avatar
hunghsingchin
Icon for Altocumulus rankAltocumulus
Jan 04, 2024

What is the behavior of the BIG-IP DNS monitor following datacenter synchronization?

I have an inquiry regarding a virtual server (VS) located in Datacenter-A, which is configured to synchronize with another datacenter, for example, Datacenter-B. This VS is equipped with a TCP health monitor that operates at 30-second intervals and is associated with a designated prober pool. My question is: Do both the VS in Datacenter-A and Datacenter-B execute the TCP health monitoring using the prober pool at the specified 30-second intervals?

if so, in the scope of destiniton ip of monitor, it will receive tcp packet every 15s ?

Thanks !

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  • whisperer's avatar
    whisperer
    Icon for MVP rankMVP
    Jan 04, 2024

    In theory, the VS doesnt really perform health monitoring. The BIG-IP does. The way this is supposed to work with prober pools, is that you want to use the local datacenter resources to monitor those origin servers which are in the same datacenter. Of course, when you create a prober pool, you must also select a datacenter. So, a resource within the same datacenter, would use a local prober pool which is assigned to the same datecenter, unless you have it hard coded otherwise. The BIG-IP in the other datecenter will receive the monitor status and metrics using BIG3D and iQuery. However, if a BIG-IP is not available, then the surviving BIG-IP will perform health monitoring directly toward the other datacenter.

    Have a look here for some additional information: https://techdocs.f5.com/kb/en-us/products/big-ip-dns/manuals/product/bigip-dns-implementations-13-0-0/17.html.