"X11Forwarding yes" causes "error: socket: Protocol not supported"

[Nigel Metheringham]

graham_guttocks at yahoo.co.nz said:
> Now openssh is disconnecting my sessions immediately after
> authentication and login with the following error messages:

> "error: socket: Protocol not supported" "Disconnecting: Command
> terminated on signal 11." 

Most likely that you have an entry in your /etc/hosts that maps your 
machine name to 127.0.0.1
X appears to special case localhost connections, and use unix sockets 
rather than inet ones.  Openssh cannot X forward from unix sockets.

You should see 127.0.0.1 in the authenticated list if you do xauth -n 
list

Change your hosts entry so that it uses the ip address of a real 
interface for this.  If your interfaces are dynamic and so you can't 
easily get an ip address, you might find you can safely set the hosts 
file value to 127.0.0.2 (really - it seems to work OK!).

	Nigel.

-- 
[ Nigel Metheringham           Nigel.Metheringham at InTechnology.co.uk ]
[ Phone: +44 1423 850000                         Fax +44 1423 858866 ]
[ - Comments in this message are my own and not ITO opinion/policy - ]