I have a production 2691 that I administer via telnet. I'd like to change that to SSH. Looking at the config, it looks like there have been keys generated in the past. I think the history here is SSH was set up, they had issues connecting, and fell back to telnet.

There are a number of crypto entries, including the following:

crypto pki trustpoint Gateway-2691.xxx.com
 enrollment selfsigned
 subject-name cn=IOS-Gateway-2691.xxx.com
 revocation-check none
 rsakeypair Gateway-2691.xxx.com

I've also got this going...

Gateway-2691#sh ip ssh
SSH Disabled - version 1.99
%Please create RSA keys (of atleast 768 bits size) to enable SSH v2.
Authentication timeout: 120 secs; Authentication retries: 3
Gateway-2691#

My question is simply, can I run crypto key generate rsa again to set it up again?

Is there a way to negate or no all of the previous ssh config so that I can start fresh there?

I may be asking the wrong questions, as I'm learning here. As for the SSH how-to, I'm sure I can find information in many places. I'm just basically wondering if I need to start fresh, or if I can pick up where the last attempt at SSH config left off.