What does it mean when SSH says the key changed?

[Red Squirrel]

I physically moved my local server to my new house and since it was offline for a while I'm forcing all the backup jobs to run now.

I got this huge warning that the host identification key changed on my web server and that I'm being hacked with a man in middle attack.

What's up with this, is that really the case, or is it just exaggerating? Is it because my IP changed from the server move?

 

[dinkumthinkum]

IP change, likely.

 

[Colt45]

Usually it only throws that if you had a different machine on the same IP before

I.e. server1 is 192.168.1.2; server2 is 192.168.1.3.
Server1 blows up in a fire.
Server2 is somehow assigned server1's old IP.
The cached key (from server1) no longer matches 192.168.1.2; because this is now server2.

That's my understanding, at least; and the only circumstances I've had when it bitches about it.

 

[Red Squirrel]

Oh ok so nothing really to worry about then? I had to clear a line in a text file to connect and I was good to go from that point.

 

[n0cmonkey]

In your case, I don't think it is something to worry about. If you had made no changes and that error popped up all of a sudden it would be something to worry about.

 

[Net]

the above could be possible. also a successful man in the middle attack would change your cert.