<p>Put a file called 'config' into ~/.ssh and you can define any option you would normally provide as part of the command as an automatically-detected configuration.</p>

<p>
For example:
</p>
<pre>
host foo
    hostname foo.org
    identityfile /home/klaatu/.ssh/foo_rsa
    port 2740
    protocol 2
</pre>
<p>
Makes the command 'ssh klaatu@foo' look like this to SSH:
</p>
<pre>
ssh -p2740 -i ~/.ssh/foo_rsa klaatu@foo.org
</pre>