Not All Cisco Routers Come with Pre-generated RSA Keys

Be careful that if you are setting up a new router to use SSH, not all of them come with pre-generated RSA keys.  If you set the input on the router to use SSH and do not have an RSA Key generated, then you will be unable to connect to the router unless you can physically console in.  We had a router returned to us from Cisco that had basic IP feature set that did not have SSH capability.  When we loaded the advanced IP feature set IOS, it did not create an RSA key for us.

Networking Cisco Router