[CRIU] Adding checkpoint/restore support to podman question

[Andrei Vagin]

On Thu, May 03, 2018 at 07:48:55PM +0200, Adrian Reber wrote:
> If you could implement the CRIU part that would be great. I have not
> started yet but I would then do the necessary changes in runc (and
> higher).

Here is a criu part:
https://github.com/avagin/criu/tree/netns_ext

Let me know if you will have any questions or comments.

Thanks,
Andrei

> 
> 		Adrian
> 
> On Thu, May 03, 2018 at 10:39:45AM -0700, Andrei Vagin wrote:
> > Hi Adrian,
> > 
> > Sorry for the late response. I think we already discussed this scheme
> > and decided that we need to add support for "external" net namespaces.
> > 
> > If you want, I can implement a criu part. Let me know if you will have
> > any other questions.
> > 
> > Thanks,
> > Andrei
> > 
> > On Fri, Apr 06, 2018 at 05:50:49PM +0200, Adrian Reber wrote:
> > > Currently I am trying to add checkpoint/restore support to podman:
> > > 
> > > https://github.com/projectatomic/libpod/pull/469
> > > 
> > > The good thing is, the basic functionality works. Right now I am trying
> > > to setup the network in podman to place the restored processes in a
> > > container with the same IP and I am confused by the network namespace.
> > > 
> > > I see CRIU has '--empty-ns' and '--join-ns' but I am not sure what is
> > > needed and correct.
> > > 
> > > My plan was to let podman set up a new network namespace with the same
> > > IP. That works. After restore I can ping the IP of the restored
> > > container, but the restored processes are now in a different namespace
> > > according to proc. So now I have the network namespace podman created
> > > with a working IP address and I have the network namespace which
> > > probably CRIU created during restore.
> > > 
> > > So right now I am confused at which levels the network namespace has to
> > > be handled. At podman or at runc, which is called by podman? Or at
> > > CRIU's level? Or do I tell CRIU to ignore the network namespace during
> > > checkpoint or restore?
> > > 
> > > If anybody has an idea what the right steps are to restore the network
> > > setup correctly that would be great! Thanks.
> > > 
> > > 		Adrian
> 
> 		Adrian
> 
> -- 
> Adrian Reber <adrian at lisas.de>            http://lisas.de/~adrian/
> Mr. Cole's Axiom:
> 	The sum of the intelligence on the planet is a constant; the
> 	population is growing.