On Mon, 27 Apr 2009, Ricardo Alzugaray wrote:

> Hello,
>
> We are trying to implement ssh passwordless access in a small cluster
> running Scientific Linux 5.2 on i386. However, it is only working (ssh no
>
> password prompt) from the nodes to the server.
>
> The /etc/hosts.equiv includes both the name of the server and the 
> computing nodes.
>
> The /etc/ssh/sshd_config was configured as follows:
>
> HostbasedAuthentication yes
> IgnoreUserKnownHosts yes
> IgnoreRhosts yes
<snip>

Fairly obviously the hosts also need to have the ssh known_hosts data for 
any machines that they will allow hostbased authentication from...

> The outputs from the node n07 to the server meyer:
>
> [rialzuga@meyer ssh]$ ssh n07 date
> get_socket_address: getnameinfo 8 failed: Name or service not known
> userauth_hostbased: cannot get local ipaddr/name
> rialzuga@n07's password:
> Mon Apr 27 13:06:22 CEST 2009
> [rialzuga@meyer ssh]$

The last error comes from openssh/sshconnect2.c where the client tries to 
look up it's own name in order to decide what info to pass to the server 
for hostbased authentication...

(the first error is from get_local_name() in openssh/canohost.c if the 
lookup of the result of gethostname fails).

So it looks like there is a problem with the DNS or /etc/hosts contents 
for the nodes.

  -- Jon