I am running CentOS 7 on a workstation and CentOS 6 and 7 on a couple of servers I am remotely connecting to using the same username and thus ssh configuration. However, one of the servers running CentOS 6 I keep getting disconnected from whereas I have no such problems with another CentOS 6 server and CentOS 7 server. The latter two are on two different hosted server setups far, far away whereas the problematic one is my own physical hardware in the same building.
I have tried to make sure the sshd configuration on all servers are identical but still have this problem. I can rule out a general problem with the router in my office since all connections are via that router, the only difference is that the problematic server is in the same building and the connection loops back via the same router but through an external IP address. /var/log/secure on the workstation offers no clues with no messages regarding any disconnection.
If anyone has suggestions what I should check, it would be greatly appreciated!