do-release-upgrade failure on Xencenter

[Arlie Stephens]

I tried to use do-release-upgrade to go from 14.04 to 16.04; instead the upgrade crashed, I was left with a somewhat functional box that thought it was on 16.04, yet still suggested I upgrade to 16.04.

Possibly relevant factors

- The system being upgraded was a virtual machine, running on Xen (the extra-cost Citrix version).In particular it announces itself as "Citrix XenServer Host 7.0.0-125380c"
- When do-release-upgrade suggested that upgrading over ssh was a bad idea, I chose to run do-release-upgrade from the Xencenter console
- The system had docker installed, from a non-ubuntu apt repository.

Behaviour seen:

- the upgrade got a long way - perhaps 2 hours before I went home
- the mess I found on the console in the morning suggested the upgrade had been asking me for input, but screen had malfunctioned in some way, putting me in a shell window with no answer expected.

I'm afraid I didn't have the sense to take a screenshot of the console (which has no scrollback), and I deleted the VM to make space to install 16.04 from scratch, before deciding I really ought to file a bug, so I have very few details for you.

However, if I'm right that the cause is basic incompatibility between some aspect of Xen (probably the Xencenter console) and do-release-upgrade, it should be trivially replicable.

Also worth knowing - naive attempts to install either 14.04 or 16.04 on this version of Xen don't work, thanks to some Citrix issue(s). See https://unyield.com/server-management/installing-ubuntu-14-04-on-xenserver-6-5-via-url-install-guide/ or http://virantha.com/2014/05/21/ubuntu-14-04-trusty-on-xenserver-62/ for the work-around required.

And finally, I believe that the Xencenter "console" device is a poor emulation of normal console behaviour. I would be totally unsurprised if the root cause of my failure is an attempt to use a tty feature that doesn't quite work right on xen.

[Ubuntu Foundations Team Bug Bot (crichton)]

Thank you for taking the time to report this bug and helping to make Ubuntu better. It seems that your bug report is not filed about a specific source package though, rather it is just filed against Ubuntu in general. It is important that bug reports be filed about source packages so that people interested in the package can find the bugs about it. You can find some hints about determining what package your bug might be about at https://wiki.ubuntu.com/Bugs/FindRightPackage. You might also ask for help in the #ubuntu-bugs irc channel on Freenode.

To change the source package that this bug is filed about visit https://bugs.launchpad.net/ubuntu/+bug/1653784/+editstatus and add the package name in the text box next to the word Package.

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[Brian Murray (brian-murray)]

Thanks for taking the time to report this bug and helping to make Ubuntu better. Could you please add the log files from '/var/log/dist-upgrade/' to this bug report as separate attachments? Thanks in advance.

[Launchpad Janitor (janitor)]

[Expired for ubuntu-release-upgrader (Ubuntu) because there has been no activity for 60 days.]