On Wed, Nov 27, 2013 at 14:37:02 +0200, Laine Stump wrote: > Awhile back a bug was filed against libvirt about the inability to > completely exclude a disk from the boot order: > > https://bugzilla.redhat.com/show_bug.cgi?id=888635 > > In short, you can't have a domain that used PXE to boot, but also has an > un-bootable disk device *even if that disk isn't listed in the boot > order*, because if PXE times out (e.g. due to the bridge forwarding > delay), the BIOS will move on to the next target, which will be the > unbootable disk device (again - even though it wasn't given a boot > order), and get stuck at a "/BOOT DISK FAILURE, PRESS ANY KEY" message > /until a user intervenes. > > It was obviously beyond the ability of libvirt to fix this (although it > can be worked around by creating a very small disk image with a > bootloader that merely instructs the system to reboot, and placing > *that* disk in the boot order just after the PXE device), so the BZ was > closed as CANTFIX. > > A couple days ago I noticed that Amos Kong had later actually fixed this > problem in seabios and qemu: > > https://bugzilla.redhat.com/show_bug.cgi?id=888633 > https://bugzilla.redhat.com/show_bug.cgi?id=903204 > > Existing behavior is preserved though, and the new behavior only comes > about if "-boot strict" is specified on the qemu commandline. > > It definitely seems desirable to have this ability in libvirt, but I'm > almost of the opinion that this should *always* be the behavior (if you > want all devices to be in the boot order, you can just give all of them > (or none of them, if you're feeling adventurous) a boot order ranking). > But I thought it would be prudent to ask opinions about that before > making any patch. > > So what are the opinions? Should the "if any devices are given a boot > order, only attempt to boot from devices that have a boot order > specified" behavior just be the default (and only) behavior when > qemu/seabios supports it? (this would imply that the old behavior is > just a bug)? Or do we need to make it configurable? I would consider the old behavior as a bug and just use -boot strict whenever we can. Jirka -- libvir-list mailing list libvir-list@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/libvir-list