Make a volume persistent on reboot

Quick and short introduction to a well known bug in nova-volume. I simply want to point it out because I think it could be useful.

A couple of weeks ago I made a strange discovery: attached volume doesn’t persist after reboot of my instance. I restarted an instance with a RBD device mapped. I did several tests like:

  • reboot within the instance: OK
  • soft reboot with nova reboot <my-instance>: BAD
  • reboot with nova reboot <my-instance> --hard: OK

Finally I came accross the bug report on launchpad (thanks to Dave Spano for the link). And this confirmed what I thought. I would say that a pretty critical bug which really needs to be fixed. It has already been patched for Folsom.

I truly hope that the code will part of the ESSEX backports.