Topics: AIX, Security, System Admin

DSH fails with host key verification failed

If you try to estabilish a dsh session with a remote node sometimes you may get an error message like this:

# dsh -n server date Host key verification failed.
dsh:  2617-009 remote shell had exit code 255
Connecting with ssh works well with key authentication:
# ssh server
The difference between the two connections is that the dsh uses the FQDN, and the FQDN needs to be added to the known_hosts file for SSH. Therefore you must make an ssh connection first with FQDN to the host:
# ssh date
The authenticity of host can't be established.
RSA key fingerprint is 1b:b1:89:c0:63:d5:f1:f1:41:fa:38:14:d8:60:ce.
Are you sure you want to continue connecting (yes/no)? yes
Warning: Permanently added (RSA) 
to the list of known hosts.
Tue Sep  6 11:56:34 EDT 2011
Now try to use dsh again, and you'll see it will work:
# dsh -n server date Tue Sep  6 11:56:38 EDT 2011

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