Sometimes, you might find that when you try and SSH into another server, it seems to hang, but then after around 30 seconds or so, will suddenly start working again. You can diagnose where it is stopping by using verbose mode.
ssh -vv user@example-server
If you find it is to do with GSS API, you can disable this in your SSH configuration.
cd ~/.ssh/ vim config
Add the following to it.
This should then speed the login up.