Forum Discussion

Kevin_M_182964's avatar
Kevin_M_182964
Icon for Nimbostratus rankNimbostratus
Feb 10, 2015

Can health monitor maintain TCP connection?

Can a TCP health monitor check be configured such that the load balancer maintains a persistent TCP connection with the pool members? I have a send string for a TCP health check, but our development...
application delivery
availability
LTM
Kevin_K_51432's avatar
Kevin_K_51432
Historic F5 Account
Feb 10, 2015

Oops, I didn't see the "in conjunction". Well, it may be worth considering if this can be used in conjunction with an ICMP (or ping) monitor?

 

I'll be sure to update this if something more fitting shows up.

 

Thanks, Kevin

 

Kevin_M_182964's avatar
Kevin_M_182964
Icon for Nimbostratus rankNimbostratus
Feb 10, 2015
I haven't been in the load balancing business very long, so I'm just guessing here, but it sounds like a passive monitor could be used to watch regular traffic going back and forth between clients and servers, and decide based on some indication from the server when to mark it as overloaded or whatever. I think the 'in conjunction' must come into play because if you were to mark a member of the pool as down, clients can't reach it, so there are no responses to check to mark it as up again, and it would be down forever. If you run the passive monitor on some traffic that is being generated as part of one of the regular health checks, there would be the possibility that the server would start responding correctly and would be enabled for regular traffic.