Speeding up SSH Logins in Ubuntu
After getting access to some new machines, I noticed that SSHing too them was excruciatingly slow, taking 5-10 seconds to ask for a password and no faster using keys. I pulled open the global SSH config file,
/etc/ssh/ssh_config on my Ubuntu machine and found a couple of GSSAPI things that were enabled by default:
GSSAPIAuthentication yes GSSAPIDelegateCredentials yes
The machines I was SSHing to don’t do GSSAPI, so every time I tried to connect my client had to wait a short timeout before trying other authentication methods. Since I don’t care about GSSAPI (few people use it), I simply set those options to
no and now my SSH sessions start much more quickly.