We are publishing Exchange 2010 services via UAG 2010.
After a short period where connectivity works as expected, clients start failing to connect and IIS fails on the UAG with the UAG Web Monitor failing to load and the system event logs showing WAS Event 5010 "A process serving application pool 'DefaultAppPool' failed to respond to ping." with the process id corresponding to the w3wp.exe process
The IIS logs show HTTP error 503 - QueueFull and netstat shows no connections from the UAG to the CAS array servers. Increasing the IIS queue length has made no difference. According to our external firewall logs connections are still being received but they're not getting past the UAG.
TMG firewall shows no dropped connections relating to the CAS addresses.
Any suggestions?