Hello,
I have a two Node Dag Exchange 2013 MultiRole server. The Usermailbox is on Node One and mounted and in Healthy status. If for some reason the Backend MSExchangeOWAapppool is stopped on Node ONE the user will not be able to access the mailbox, even though the Node Two Mulit role is up and functional. Healthchecks on the (netscaler) load balancer still direct owa requests to node ONE even though the pool has failed and the node is down. If I remove the load balancer it acts the same way. Is the component level failure not detected in Exchange 2013?