On Fri, Oct 9, 2009 at 3:18 AM, Daniel P. Berrange <berrange@xxxxxxxxxx> wrote: > On Thu, Oct 08, 2009 at 10:57:55PM -0500, Dustin Kirkland wrote: >> Now, all of that said, it is actually possible to hot-add a second >> scsi device. However, as far as I can tell, this method is not yet >> supported by libvirt. It looks to me that with modern qemu, you have >> to do it this way: >> >> Drop to a qemu console with ctrl-alt-2. Get the address of the current scsi bus: >> (qemu) info pci >> Look for "SCSI Controller". In my case, it's on Bus 0, device 4, function 0 >> >> Now instead of pci_add, use drive_add >> (qemu) drive_add 0:4 file=/tmp/foo,if=scsi >> OK bus 0, unit 1 > > That is correct - the SCSI driver hotplug in libvirt is not implemented > in the right way. If you specify multiple SCSI devices at boot, they > all get on one controller, if you hotplug multiple SCSI devices, we're > hotplugging a new SCSI controller per disk. This is clearly not good, > because when you then reboot, all those controllers are merged back into > one. Okay, in our previous usage of this, rebooting didn't matter very much. > There is a guy who is working on implementing the correct SCSI hotplug > approach for libvirt, that is still work in progress though. The most > recent patches were here: > > http://www.redhat.com/archives/libvir-list/2009-September/msg00551.html > > We will ultimately support hotplug of both drives, and drive controllers > independantly, giving apps/users the flexibility they need. Thanks. I'll track those patches with interest. :-Dustin -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
