I have a recurrent problem from more month. We have always the same message on SharePoint Servers
Event 3355 SharePoint Foundation - Critical
Cannot connect to SQL Server. "Name Alias DSN" not found. Additional error information from SQL Server is included below.
Timeout expired. The timeout period elapsed prior to completion of the operation or the server is not responding.
Event 3351 SharePoint Foundation - Critical
SQL database login for "Name Database Farm configuration" on instance 'PName Alias DSN' failed. Additional error information from SQL Server is included below.
Login failed for user 'NT AUTHORITY\ANONYMOUS LOGON'.
And in fact, we can have often error message on Webapplication "RunTime Error". We have to recycle application pool and warmup site and situation come back ok..
We had runned an action plan with Disable TCPChymney but not effect positive.
Have you an idea ?