[nova] Rebuild from cell0 limitation for personality files
On 04/10/2019 11:30 AM, Matt Riedemann wrote:
> I wanted to get some wider attention on what I think will be a
> limitation in the rebuild from cell0 spec . The main idea in that
> spec is the user tries to create a server which fails during scheduling
> to find a host and puts the instance into ERROR state and "buries" it in
> cell0. With a new microversion, the user can attempt to rebuild the
> server from cell0 and go through scheduling again. This is part of a
> bigger effort to support pre-emptible instances where scheduling fails
> during server create, an external reaper service tries to make room by
> destroying some pre-emptible instances, and then the server gets rebuilt.
> The issue I've found is that if the server was created with personality
> files using microversion 2.1, fails, and then the user goes to rebuild
> it, their personality files will be lost because (1) we don't persist
> personality files anywhere, not even the RequestSpec and (2)
> microversion 2.57 deprecated the personality files parameter from the
> rebuild API . Since you'll have to use a newer microversion > 2.57 to
> rebuild from cell0, you can't specify the personality files again.
> Are we OK with this?
Ummm, yes. Yes, I am completely OK with this.