Thank you for taking the time to report this bug and helping to make Ubuntu better.
I think we have seen some other reports of mysql_upgrade failures like this but so far had been unable to reproduce and did not have a technical explanation. Thank you very much for providing this. We can probably duplicate other reports to this bug.
Separately, we're overhauling how mysql_upgrade is called due to bug 1592669. Our planned solution for that bug is to no longer use invoke-rc.d to start mysqld before running mysql_upgrade at all. Instead we'll run a "private" daemon that runs with networking and ACLs disabled in a root-only private socket so that mysql_upgrade can then run unhindered, and then shut it down again. So when that bug is resolved, I think this (looks valid) bug will become moot.
Thank you for taking the time to report this bug and helping to make Ubuntu better.
I think we have seen some other reports of mysql_upgrade failures like this but so far had been unable to reproduce and did not have a technical explanation. Thank you very much for providing this. We can probably duplicate other reports to this bug.
Separately, we're overhauling how mysql_upgrade is called due to bug 1592669. Our planned solution for that bug is to no longer use invoke-rc.d to start mysqld before running mysql_upgrade at all. Instead we'll run a "private" daemon that runs with networking and ACLs disabled in a root-only private socket so that mysql_upgrade can then run unhindered, and then shut it down again. So when that bug is resolved, I think this (looks valid) bug will become moot.
I subscribed Lars for his attention.
Thank you again for the report.