This is an alternative to T90821 'Upgrade labs cluster to Trusty.' The process would differ because we would have to reimage hosts rather than doing in-place upgrades.
Debian support for OpenStack is looking reasonable these days; indeed I've encountered some criticism that the Ubuntu packagers are slacking off and just porting things in directly from Debian. I can see for myself that that's the case for Designate -- there aren't any official Trusty packages for Designate at all. Nonetheless it would be best to do some more research before choosing this path.
Cons:
Following this course would require purchasing some new hardware. We'd need replacements for labnet1001, virt1000, and at least one spare HP virt node. Those last two are things we really need to do anyway though.
Pros:
- A reimaging upgrade path would open up the possibility of live-migrating instances and avoiding reboots. (Note that it's possible to do a reimaging upgrade on Trusty as well, given the same hardware.)
- Jessie is the future of Ops, so maybe we should just skip Trusty if we're upgrading anyway.
- I'm currently stumped/embittered at the lack of Designate packages for Ubuntu, and this path would definitely solve that!