cubicweb #2632425 [doc] instances not restarted during Ubuntu package upgrades [validation pending]

I upgraded CubicWeb form 3.15.4 to 3.15.8 using Logilab's Ubuntu packages on a 12.04 LTS server. A CubicWeb instance based on the Brainomics cubes (got them via Hg) was already running, it had been started manually using cubicweb-ctl. This instance was neither upgraded nor restarted during the CubicWeb upgrade. No warning was printed.

The next day when attempting to access the Brainomics instance, it would respond very slowly and I could barely connect to the server itself using SSH. CubicWeb eventually segfault'ed.

After rebooting the server, I tried to restart the Brainomics instance and at last got a warning :
$ cubicweb-ctl start localizer instance localizer not started: instance has cubicweb version 3.15.4 but 3.15.8 is installed. Run "cubicweb-ctl upgrade". $

After upgrading the Brainomics instance I was able to restart it.

I believe there are a few issues here:

  1. I do understand the scripts in the Ubuntu package might not have enough information about all running instances, on how they were started - they might not even have access to relevant directories when mouting remote file systems. Then maybe CubicWeb should be modified so that the root account has access to such information.
  2. I wasn't able to find documentation on CubicWeb upgrades for sysadmins. I did find some information on upgrading cubes for developpers. There's also a paragraph on instance upgrade. But then what is meant by instance upgrade - CubicWeb upgrade or application cube upgrade or both?

5.2.2. upgrade

8.1. Migration scripts management

done in3.21.0
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closed by<not specified>
patch[book] typos / clarifications in create-instance section [applied]