A couple of week ago we finally moved the last lingering VMs in our OpenStack platform from the nova-network region to the Neutron region (Blog Post: Neutron is here!). The bulk of the work had been done a month earlier, so the final nails in nova-network's coffin felt a bit anticlimactic -- nevertheless, this is a big step that represents a huge amount of work on the part of both staff and volunteers.
VPS and Toolforge users have been extraordinarily patient with all of the downtime, deprecations, and hand-tuning that this change required. The lack of grumbles did not go unnoticed -- it's great to work with such a supportive group of users. Thank you!
Our reliance on the long-obsolete nova-network service was blocking many, many things. Now that it's gone, we can...
- Officially discontinue support for Ubuntu Trusty throughout the WMF's infrastructure. (some of the last Trusty servers were supporting nova-network)
- Shut down and decommission half a dozen long-obsolete servers.
- Rip out hundreds of lines of special-case puppet code that supported the old nova-network OpenStack region.
- Upgrade our OpenStack Nova services past version Mitaka. (Mitaka was the last release that supported nova-network; there have been SIX upstream releases since Mitaka)
- Upgrade Horizon.wikimedia.org to run newer versions with fancier panels. (Previously we were stuck running the last version that supported nova-network)
- Switch to a less buggy Designate/DNS model that should result in fewer VM creation failures and fewer DNS record leaks.
- Possibly spend some time on other WMCS features that aren't 100% dedicated to repaying technical debt.
Most of those changes will be invisible to the end-users, but will make for much happier operations staff!