Open Stack

As a follow-up, I've filed this bug:

https://bugs.launchpad.net/nova/+bug/1266262

We'll be working around this in TripleO by setting
default_ephemeral_format for our baremetal clouds, but I feel we should
document in Icehouse's release notes that the default will be changed
to ext4 in Juno, so that deployers can set it to ext3 in their Icehouse
deployments.

The question I'd have is should we print a warning if users leave it
unset in their configs in Icehouse so they know what to expect in Juno,
or is the documentation enough?

Excerpts from Day, Phil's message of 2013-12-29 00:12:50 -0800:
> Hi Folks,
> 
> As highlighted in the thread "minimal review period for functional changes" I'd like to propose that change is https://review.openstack.org/#/c/63209/ is reverted because:
> 
> 
> -          It causes inconsistent behaviour in the system, as any existing "default" backing files will have ext3 in them, so a VM will now get either ext3 or 3ext4 depending on whether the host they get created on already has a backing file of the required size or not.   I don't think the existing design ever considered the default FS changing - maybe we shouldn't have files that include "default" as the file system type if it can change over time, and the name should always reflect the FS type.
> 
> 
> 
> -          It introduces a new a new requirement for GuestOS's to have to support ext4 in order to work with the default configuration.   I think that's a significant enough change that it needs to be flagged, discussed, and planned.
> 
> 
> 
> 
> 
> I'm about to go off line for a few days and won't have anything other than patchy e-mail access, otherwise I'd submit the change myself ;-)
> 
> 
> Phil