Greetings. We been having issues with our 2012 AG lately and typically see messages like these below:
A connection timeout has occurred on a previously established connection to availability replica '' with id []. Either a networking or a firewall issue exists or the availability replica has transitioned to the resolving role.
Message
A connection timeout has occurred while attempting to establish a connection to availability replica '' with id []. Either a networking or firewall issue exists, or the endpoint address provided for the replica is not the database mirroring endpoint
of the host server instance.
I actually didn't realize until today during research that there are actually two different (but similar) error messages. At any rate, changing the Session Timeout setting in the AG seems like a common recommendation once past the network/ firewall theories. My question is what are the potential negative impacts of doing this? I've been researching this topic for a while today and can't find any downsides to this. If it's OK to make them longer, why is a measly 10 seconds the default?
Ours are currently set to 30 seconds, but I'm wondering if they should be longer. My guess is it wouldn't hurt since our AG unfortunately houses a large Data Warehouse environment so there is a LOT of data getting transferred between these two nodes during heavy ETL times.
Thanks!
Thanks in advance! ChrisRDBA