Warnings with Putty tool while working on Linux machine

[Pawan Sangal]

Hi,

Iam using Putty tool on my desktop PC to connect to my linux machine (telnet). After logging in and jumping to desired directory location. While, Iam trying to exeute some scripts I am getting WARNING messages in Putty window.

If I am doing the same thing from any other Desktop PC using same Putty tool, I don't get any messages as mentioned below.
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@ 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

9a:g4:b6:51:9d:f3:c6:c3:32:dc:r4:c6:gh:bn:7a:44.

Please contact your system administrator.

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

Offending key in /projects/PKS/home//.ssh/known_hosts:203

Password authentication is disabled to avoid man-in-the-middle attacks.

X11 forwarding is disabled to avoid man-in-the-middle attacks.
---------------------------------------------------------------------

Is this related to any settings problem with my Putty on my Dekstop PC ?

Please help, if you have any solution against this problem..

Thanks
Pawan sangal

[Ben Cotton]

Has the machine you're logging in to been re-installed or upgraded since the first time you logged in? That's generally the most common cause of that message.

[Pawan Sangal]

Hi Ben,

Yes, you're correct with your assumption, actually the system was re-imaged and thus the host key (ssh-rsa) for the system got changed. I opened the "known_hosts" file under ".ssh" directory of the system and removed the lines from the knwon_hosts file having the system name, IP and host key of the target system against which I was getting the mentioned message while logging in.

If, you delete that particular line from the file, you will get a message like the one that you saw when you connected to a server for the first time.

On re-login, I didn't get the message, as I was getting earlier. Now, it is working fine.

Thanks a lot for your help....

Regards,
Pawan Sangal