Is your workstation kerberized or using some other form of enhanced NFS
security? In order to display the unlock dialog, xscreensaver forks off
a new process that has to authenticate itself to the X server, which
usually involves reading $HOME/.xauthority, which it may be unable to do
if your home directory access credentials (kerberos tickets for instance)
have expired.
You may be able to workaround this by always giving your userid permission
to access the X server, via 'xhost +si:localuser:mschuster' (or whatever
your username is), but I haven't verified that the fallback works if
$HOME is unreadable. (I wonder if it makes sense to make this be set by
default in X session setup, to allow X apps to start when the NFS server
for $HOME is unreachable, but that would need thinking about the security
implications.)
xscreensaver could also prevent this by always forking the GUI as soon as
it locks, having it XOpenDisplay() then and not display the window until
needed - that would probably also give better response time to the normal
case as well, but that's a redesign of the current implementation.
-Alan Coopersmith- alan.coopersmith at sun.com
Sun Microsystems, Inc. - X Window System Engineering
michael schuster wrote:
> All,
>
> I hope these are the right places for this question - if not, please
> redirect and keep me on CC. thx.
>
> I've been sucessfully accessing a vnc session running on my workstation
> in Menlo Park for the last few weeks. Today I tried to access this
> session, only to find that I couldn't unlock this session if it had been
> inactive for a few hours.
>
> here's what I did:
> while in the Bay Area
> - logged out of my X session on my workstation (just in case anybody
> wanted to use it ;-)
> - ssh'd into my WS and ran 'vncserver ....'
> - ran 'vncviewer ...'
> all without issue. Unlocking a session that had been idle overnight or
> over the weekend: no problem.
>
> this morning, in Europe, I
> - punched in (to .sfbay)
> - tried the same 'vncviewer ...' command. All I got was a black screen
> (ie the dialog prompting for my password didn't come up)
> - after some time (5 minutes?), I ssh'd into my WS, 'vncserver -kill'ed
> the vnc session, started a new one.
> - 'vncviewer ...' worked fine (if noticably slower, what a surprise ;-)
> - locking and immediately unlocking worked fine.
> - punched out (including killing vncviewer), closed down laptop, left
> for extended lunch break
> - punched back in, vncviewer again shows me only blank screen. I waited
> a little, no change. I even tried remote display of a vncviewer running
> on my WS (it was sluggish), but I didn't get to unlock the session.
>
> TIA for any ideas.
> Michael
