I rebooted my TeamCity server following updates.
When I start the TeamCity agents they report a 500 Internal Server Error and the login page (http://teamcity-server:8080) reports the error:
SQL exception: Cannot open database requested by the login. The login failed. ClientConnectionId:f17b1159-b183-4241-bc98-c119d1767b49
The issue is that the TeamCity Server service is starting and requesting database access before the MSSQL services are ready.
Quick Fix: Restart the TeamCity Server service (sc stop teamcity && sc start teamcity)
Long-term Fix: Change the TeamCity Server service startup type from Automatic to Automatic (Delayed) (sc config teamcity start= delayed-auto)
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