I have a virtual server machine that has multiple SQL instances installed (2 x 2008 R2, 1 x 2012, 1 x 2014)
There are database on all the instances.
Users can work remotely (from their computers) on those instances using SSMS or a delphi application. After a certain time (random), random users start experiencing issues with the connection.
The behavior is the following when the connections issues start:
- SSMS can connect to any instance, but right after that if I try to use the object explorer to open the database list it hangs (connection time out). The only user used for both SSMS and the delphi app is the SA user of sql.
- The application also manages first link (the first query is succesful), but after that, OLE DB error, connection time out
- I tried to connect using CMD and it works, but not entirely. What I can do is select specific columns from tables, but I am not able to run a query such as "select * from table"
- If the server is restarted everything is ok again but only for a while.
The SQL instances were installed according to Microsoft recommendations: starting with the oldest version first
The windows user the installation was done under is administrator. Firewall has been checked and rechecked.
Has anyone encountered something similar or has any ideas what to check?
Thank you very much