From mboxrd@z Thu Jan  1 00:00:00 1970
From: Greg Kurz <gkurz-NmTC/0ZBporQT0dZR+AlfA@public.gmane.org>
Subject: Re: C/R and stdio redirection
Date: Wed, 08 Sep 2010 12:00:33 +0200
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To: Louis Rilling <Louis.Rilling-aw0BnHfMbSpBDgjK7y7TUQ@public.gmane.org>
Cc: Dan Smith <danms-r/Jw6+rmf7HQT0dZR+AlfA@public.gmane.org>, Sukadev Bhattiprolu <sukadev-23VcF4HTsmIX0ybBhKVfKdBPR1lH4CV8@public.gmane.org>, Containers <containers-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org>, Nathan Lynch <nathanl-V7BBcbaFuwjMbYB6QlFGEg@public.gmane.org>
List-Id: containers.vger.kernel.org

On Wed, 2010-09-08 at 10:41 +0200, Louis Rilling wrote:
> I think that this should be solved by a file substitution facility combined with
> an ability to ignore "unsupported files" at checkpoint.
> File substitution is the ability to tell sys_restart() to substitute some of
> caller's file descriptors to checkpointed file descriptors.
> Ignoring "unsupported files" means that the checkpoint could record that a given
> file descriptor was shared by some files_struct, but the file descriptor itself
> is not checkpointed because of various reasons, like file descriptor outside
> the container, unsupported file systems, etc.
> 

Metacluster (old IBM proprietary C/R solution) had also a similar
mechanism. This is the only sensible way to C/R a container with
inherited descriptors.

> Both of those mechanisms have been developed in Kerrighed, and Matthieu (in Cc)
> should start a discussion about this in the next weeks.
> 

Matthieu doesn't appear on the Cc line...

> Thanks,
> 
> Louis
> 

Regards.

-- 
Gregory Kurz                                     gkurz-NmTC/0ZBporQT0dZR+AlfA@public.gmane.org
Software Engineer @ IBM/Meiosys                  http://www.ibm.com
Tel +33 (0)534 638 479                           Fax +33 (0)561 400 420

"Anarchy is about taking complete responsibility for yourself."
        Alan Moore.