Re: reverse mapping -- POSSIBLE BREAK-IN ATTEMPT

On Tue, 13 Feb 2007 21:11:16 +0100 (CET), Unruh <unruh-spam@xxxxxxxxxxxxxx> wrote:
Ignoramus21592 <ignoramus21592@xxxxxxxxxxxxxxxxxxxx> writes:

I am doing ssh from one host A, which I control, to another host B,
which I also control. Nothing has been compromised.

When I do ssh from A to B, I get this error message:

reverse mapping checking getaddrinfo for Z failed - POSSIBLE BREAK-IN ATTEMPT!

(A, B and Z are used instead of actual host names to protect privacy).

This means that the remote host has IP address I, and reports its name to
be B, but if one tries to resolve the name B one does not get address I.

Yes.

This seems to be a simple issue of host B having a wrong reverse IP
resolution (provided by my ISP authority record) that maps the IP of B
to Z instead of B. And SSH does this paranoid check of reverse of B
and complains since it finds that B is not B but Z.

Yes. So why is this true?

I am only interested in how to turn it off.


I have no desire to waste time talking to my ISP begging them to set
up reverse resolution etc.

I just want SSH to stop complaining about this error.

so, you do not mind increasing the probability that you connnect to a
rogue site.

Yes.That's correct, in this instance.


I did google a lot about this message, and it seems that almost
everyone making comments on this has NO CLUE. (as they talk about
hackers, brute force attacks etc).

How about VerifyReverseMapping?

It is not defined either in man ssh, nor in man sshd_config.

Or UseDNS?

Already tried, does not help, and why should it since this is a client
problem.

i

man sshd_config


So, I would like to hear from someone WITH A CLUE as to what SSH
option to set as to get rid of this warning.

Thank you.

.

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