I am getting the below message when trying to ssh to my router.
I got this message when I switched ports of the ethernet cable from the Tp-link wr703n router to my cisco router.
Previously it was fine.

nanotech@nanotech-laptop:~$ ssh root@192.168.1.12

@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
@    WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED!     @
@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
IT IS POSSIBLE THAT SOMEONE IS DOING SOMETHING NASTY!
Someone could be eavesdropping on you right now (man-in-the-middle attack)!
It is also possible that the RSA host key has just been changed.
The fingerprint for the RSA key sent by the remote host is
62:b0:0b:08:bd:0e:c6:e3:dd:33:d9:1d:a3:ff:1c:47.
Please contact your system administrator.
Add correct host key in /home/dave/.ssh/known_hosts to get rid of this message.
Offending key in /home/dave/.ssh/known_hosts:3
RSA host key for 192.168.1.12 has changed and you have requested strict checking.
Host key verification failed.

When put in below command ssh-keygen -f .ssh/known_hosts it is prompting me to enter passphrase

What is this & how to I reconnect to my router using ssh

(Last edited by davebdublin on 18 Apr 2014, 16:47)

Is because of a pub key for IP address 192.168.1.2 in known_hosts file is different as pub key offered from router. Did you changed router or IP address on it? If yes, just remove known_hosts file.

"Add correct host key in /home/dave/.ssh/known_hosts to get rid of this message."

just remove known_hosts,
rm ~/.ssh/known_hosts

and then again ssh into router