ssh identification failed

[catastro]

Hi all. I have a little problem with ssh.
Thi message appears qhen I try to access with ssh to my system:

desar:/root# ssh root@testi1
@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
@ WARNING: POSSIBLE DNS SPOOFING DETECTED! @
@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
The RSA host key for testi1 has changed,
and the key for the according IP address 10.57.224.83
has a different value. This could either mean that
DNS SPOOFING is happening or the IP address for the host
and its host key have changed at the same time.
Offending key for IP in /opt/ssh/etc/ssh_known_hosts:69
@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
@ 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
dc:fc:38:a3:01:f1:22:86:06:69:92:0e:56:f9:27:f2.
Please contact your system administrator.
Add correct host key in /root/.ssh/known_hosts to get rid of this message.
Offending key in /root/.ssh/known_hosts:14
RSA host key for testi1 has changed and you have requested strict checking.
Host key verification failed.

How can I solve this issue? Thanks a lot.

[Frank_W · Accepted solution]

The problem is clearly discribed:

the ssh server "10.57.224.83" changed and now has a different host key ( new installation? new hostname? clusterswitch? ... ). Or its a man-in-the-middle attack.

if you are shure its not an attack:

delete line 14 in /root/.ssh/known_hosts on you r client an try again.

[Jeeshan]

go through the guide

http://docs.hp.com/en/5991-7493/index.html

[catastro]

Thanks to both f you. I didn´t know what to do for restoring the keys. I didn´t thought that I could remover the keys form the text just by editing the file. Now everything works just fine. Thanks a lot.