On Fri, Sep 29, 2017 at 09:06:01AM +0200, Michal Privoznik wrote: > https://bugzilla.redhat.com/show_bug.cgi?id=1434451 > > It comes handy for management application to be able to have a > per-device label so that it can uniquely identify devices it > cares about. The advantage of this approach is that we don't have > to generate aliases at define time (non trivial amount of work > and problems). The only thing we do is parse the user supplied > tag and format it back. For instance: > > <disk type='block' device='disk'> > <driver name='qemu' type='raw'/> > <source dev='/dev/HostVG/QEMUGuest1'/> > <target dev='hda' bus='ide'/> > <alias user='myDisk0'/> > <address type='drive' controller='0' bus='0' target='0' unit='0'/> > </disk> > > Signed-off-by: Michal Privoznik <mpriv...@redhat.com> > --- > > An alternative approach to: > > https://www.redhat.com/archives/libvir-list/2017-September/msg00765.html > > Honestly, I prefer this one as it's simpler and we don't have to care about > devices changing their aliases on cold plug. I mean, on cold (un-)plug we'd > have to regenerate the aliases so it might be hard to track certain device. > But with this approach, it's no problem.
Can you elaborate on you mean by the cold plug problem here ? Are you saying that if you cold plug a single device, we would regenerate aliases on every single other device too ? I would surely think we can avoid that kind of thing. To make hotplug easier for applications we could add a V2 hotplug API which *returns* the fully-expanded device XML. That way applications would immediately learn the alias of the newly hotplugged device in a simple manner. While we were at it, this would give us opportunity to make the v2 hotplug API support hotplugging of multiple devices at once. This is a feature we've needed for PCI assignment where some devices have to be co-assigned at the same time. Regards, Daniel -- |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| |: https://libvirt.org -o- https://fstop138.berrange.com :| |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :| -- libvir-list mailing list libvir-list@redhat.com https://www.redhat.com/mailman/listinfo/libvir-list