7.14. Using Comments to Label Keys

Problem

You have a lot of SSH keys, and you would like a simple way to identify the public keys after they are transferred to your known_hosts and authorized_keys2 files.

Solution

Use the comment option when you create a key to give it a descriptive label:

	$ ssh-keygen -t rsa -C "mailserver on jarlsberg"

The key looks like this:

	ssh-rsa
	AAAAB3NzaC1yc2EAAAABIwAAAIEAoK8bYXg195hp+y1oeMWdwlBKdGkSG8UqrwKpwNU9Sbo+uGPpNxU3iAjRa
	LYTniwnoS0j+Nwj+POU5s9KKBf5hx+EJT/
	8wl70KyoyslPghsQAUdODoEwCzNFdIME8nm0vxzlAxS+SO45RxdXB08j8WMdC92PcMOxIB1wPCIntji0=
	mailserver on jarlsberg

This is helpful when you have a lot of keys in known_hosts and authorized_keys2 because even though you can give the keys unique names, the keynames are not stored in these files.

Discussion

OpenSSH ignores the comment field; it's a convenience for human users.

See Also