[Libguestfs] guestfsd process dead while quitting guestfish

[Richard W.M. Jones]

On Thu, Sep 13, 2012 at 05:52:35PM +0800, Richard Huang wrote:
> I've compiled guestfsd and run it on CentOS 6.3. It worked well, but when I
> quit guestfish, the guestfsd process in guest is always dead itself
> automatically. Is this a bug? or did I miss something?

This is intentional, and also a bug.

libguestfs-live currently has a limit of one user at a time.  We
normally run it from systemd which restarts guestfsd after each
user.  See:

http://pkgs.fedoraproject.org/cgit/libguestfs.git/tree/guestfsd.service

The limit of one user at a time makes sense for regular libguestfs,
but not so much for libguestfs-live, where we could easily support
multiple parallel users.

However the reason we don't support that is because we have only one
virtio-serial channel with a fixed name
(/dev/virtio-ports/org.libguestfs.channel.0).  virtio-serial channels
are not multiplexed, and they have to be created in advance [AFAIK --
is this still true?] so you would always have a very awkward situation
where max N users are supported concurrently (at the moment, N=1).
Assuming we stick with virtio-serial for the libguestfs-live case and
don't use something more normal like TCP/IP.  So that's why this is
also a bug.

Fixing it isn't too hard TBH, but no one cares enough about this
use-case to have sent any patches so far.

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
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