Docs don't mention running console proxies per cell

[Matt Riedemann]

This came up in the mailing list today:

http://lists.openstack.org/pipermail/openstack-discuss/2019-September/009827.html

It's not immediately obvious that console proxy services should be run per-cell rather than globally.

One would expect to see something about that here:

https://docs.openstack.org/nova/latest/user/cellsv2-layout.html

and/or here:

https://docs.openstack.org/nova/latest/admin/remote-console-access.html

or even in the cells FAQs page:

https://docs.openstack.org/nova/latest/user/cells.html#faqs

There was a lot of confusion over the deprecation of the nova-consoleauth service in Rocky and several release notes and workarounds for that:

https://docs.openstack.org/nova/stein/configuration/config.html#workarounds.enable_consoleauth

[melanie witt (melwitt)]

This used to be mentioned in the docs and I looked and found it got removed by this commit:

https://github.com/openstack/nova/commit/009fd0f35bcb88acc80f12e69d5fb72c0ee5391f