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Forum Discussion

Funkdaddy's avatar
Funkdaddy
Icon for Nimbostratus rankNimbostratus
Apr 15, 2020

Pool setting: "Action On Service Down" set to "Reject" for loaded Pool - bad?

We have a Pool (HTTP) that hosts thousands of connections at any given moment, and the pool has "Action On Service Down" (link to F5 Article below) set to "Reject". We've had a few incidents where we...
application delivery
LTM
Simon_Blakely's avatar
Simon_Blakely
Icon for Employee rankEmployee
Apr 15, 2020

> Am I characterizing this correctly and do my assumptions seem sound?

 

Pretty much.

 

> What drawbacks to using "None" over using "Reject"?

 

None allows the chance that the pool member may still service the connection even though the monitor is down. This may work. It may not. None will be slower than Reset.

 

> How do I know how long a request or connection will remain on the DOWN-ed server if it doesn't come back up? Is that a TCP timeout?

 

It will be the TCP Retransmission Timeout, not the TCP Idle Timeout

 

> Anything else I'm missing?

 

Not really. Just don't use Reselect unless you are loadbalancing stateless routers.