BOFH Hunter

SSH is a staple of *nix environments, however most people don’t take the time to customize it in order to take advantage of the deeper features. If you have more than a few machines to log into or administer, it’s pretty likely that you’ve also got a few usernames to go along with them. By creating a personal ssh config file, you can shave a few seconds and a few keystrokes off your logins. You can even create profiles for several user accounts on the same machine if you have specific task based logins.

To get started with your own personal config file, create and open ~/.ssh/config in your favorite text editor. The easiest way to organize this file is to break it up into host based sections, similar to the example below.

Host SessionName # Short Name you can use to start a session
HostName server.example.com # FQDN or ip of the server
User myuser # Unprivileged username for this session

Host Session2
HostName server.example.com
User myadminuser #this is a 2nd user with sudo access to the same server
IdentityFile id_rsa

Host server2
HostName server2.example.com
User yetanother # yet another user on another host.
IdentifyFile second_rsa_key
Compression yes #server has limited bandwidth, so enable compression

Host backup
HostName backups.example.com
User backupuser # backup user
BindAddress 192.168.1.2 #Connect from this ip address.
Port 2222 # Use this port instead of 22.

As you can see from the example above, we change ssh keys so you don’t have to use the same one, ssh usernames to eliminate the @, and the address ssh connects from since we have multiple IP addresses on this system. This isn’t really even scratching the surface of what you can do with ssh, so if you have even more customizations in mind, have a read through the ssh_config manpage in your favorite terminal.