mac os x ssh keys - remote machine names

Question

I'm working on getting keys set up so I can easily log in to my servers. I know I can do things like: "ssh user@example.com", but I have some servers that don't have a domain name. They have ip addresses (mainly database servers). Is there a way to type in something other than "user@1.2.3.4.5" and instead type something like "user@myfavdatabase"? Basically a way to create an alias for ip addresses or something?

Answer 1

You can use an ssh config file in your home directory. For example:

[user@host ~]$ cat .ssh/config 
Host myfavdatabase
  User user
  Hostname 1.2.3.4

See man ssh_config for more information.

Answer 2

Also, since you wrote about keyS in plural, adding the IdentityFile directive could be also useful in your ~/.ssh/config

Host myfavdatabase
  User user
  Hostname 1.2.3.4
  IdentityFile ~/.ssh/a_ssh_private_key_for_myfavdatabase

Also remember that you can create keys without password just by pressing enter when ssh-keygen prompts for a password.

If you go the more secure way of having a password, you can always add the password once to the ssh-agent using

ssh-add ~/.ssh/a_ssh_private_key_for_myfavdatabase

and typing your password only once. The ssh-agent will cache your password for future connections, at least until next logout or reboot.