GTM collection server

We have 2 GTMs in a sync group, each in a separate data center. They are synced with LTMs across 3 data centers, all is good there.

 

 

On the GTMs we have a handful of standalone 'generic host' web servers defined, although up and responding on https, we noticed some would show red https health check, and 1 would flap up and down every so often.

 

 

We dialed in the problem to the statistics collection server. When set to auto neither of our GTMs are sending the health checks. I'm not sure what order/criteria are used with auto select, but it's obvisouly not the same one as I can see that one generic host flap from green to red every 30 seconds or so, and I don't see any health checks from the GTMs on the red host.

 

 

We can manually set the collection server to one of the GTMs and the servers show green, no flapping, however since the GTMs are synced both GTMs have the same GTM as the collection server. We are v10, I know in v11 you can create a prober pool which would solve our problem, but I'm not sure the best way to set this up on v10.

 

 

If we set GTM 1 as the collection server for a host on both GTMs, and GTM1 goes down, will the health check then erroneously fail, or would it transition to auto?

 

 

Is the best bet removing sync between the GTMs and having GTM1 use itself as the collection server for its standalone hosts, and GTM2 using itself as the collection server for its standalone hosts? Or some type of workaround to use both GTMs as the collection servers?

 

 

Thanks