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Having some strange issues when we put our Exchange Servers in maintenance mode when doing a CU update. We have 4 Servers and 2 DAGS, when we put the primary server into maintenance mode, we get disconnected in Outlook. Everything else works fine, Webmail, E-Mail to phone, just not Outlook. Does anyone have any suggestions on what might be causing this? When I do a test in Outlook, it is pointing to the correct Internal/External URLS and the test comes back fine. It just will not connect to the Database on the failover server?
Setup
Exchange 2016
4 Servers
2DAGS
Kemp Load Balancer
Thanks,
Gavin
I would look here > Kemp Load Balancer
Something isnt set right or the Kemp isnt configured to mark the server in maint mode down.
I manually take the server down in the LB, I even took the LB out of the equation by pointing directly to the failover server and still had the same problem. Not sure why it will not connect to the DB, If I manually move the DB to the failover server, everything works fine, its just when the server is in maintenance or offline, which defeats the purpose of the DAG when the primary goes down.
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When no servers are in maint mode, activate a database in secondary server, does the user of that database loses Outlook connection?
No, it works fine. Outlook stays connected.
Check the IIS log when outlook fails, is there outlook connection created?
When you set to maint mode, do you also reboot the server after that to clear any connections?
No, I have not rebooted the server. I will give that a try the next time I run an upgrade.