cloud-init-dev team mailing list archive

["Haefliger, Juerg" <Juerg.Haefliger@xxxxxx>]

All,

OpenStack supports a rescue feature that allows a user to try to fix a broken instance. The way it works is that if you engage it, a new instance (the rescue instance) is booted using the same Glance image as the 'broken' instance and the root disk of the broken instance is attached as a second disk to the rescue instance. The problem is that both disks have the same filesystem UUIDs (since they're both based off the same Glance image) which seems to confuse the guest kernel. Sometimes things work as expected and sometimes the two disks are swapped.

I'm wondering if we should extend cloud-init to change the UUIDs on first boot. Obviously we'd have to also change it in all the places where it's being used (/etc/fstab, /boot/grub/grub.conf, ...) or the instance becomes unbootable (which makes me just a little bit nervous).

Comments? Suggestions?

Thanks
...Juerg