To troubleshoot login time-out error, a new XEvent is added in SQL Server 2017. This can be used to troubleshoot network disconnection or slowness during a login attempt. You can enable sqlserver.security_authentication_perf_interrogate_login event to collect data.
This improvement is included in the following cumulative update for SQL Server:
About cumulative updates for SQL Server:
Each new cumulative update for SQL Server contains all the hotfixes and all the security fixes that were included with the previous cumulative update. Check out the latest cumulative updates for SQL Server:
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