Add some diagnostics to do-release-upgrade when it can't find a release

[Dave Gilbert]

every LTS+1 those of in +1 see zillions of people asking why do-release-upgrade -d won't find them their new release;
it doesn't tell them why there was 'No new release found'.

So I'd like to see it say something like:
   No new release found; do-release-upgrade is configured to only look for new LTS releases (see ....)

Dave

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Dennis De Matteis (i-dennis)]

Hi there,

I've searched a bit among existing reports and i think/hope this is the right place to add my information.
I recently struggled about important information which is missing when executing do-release-upgrade on Ubuntu 12.04 LTS.
After execution it reported: no new release found
even though Ubuntu 14.04. LTS is available.

As far as i understood, do-release-upgrade checks servers mentioned in /etc/update-manager/meta-release for upgrades.
I figured out that the the effected machines have links to local repositorys which allows e.g. "apt-get update" and "apt-get upgrade" to work. However no local records for the meta-release files are given and the local network configuration blocks requests to:
http://changelogs.ubuntu.com/meta-release and
http://changelogs.ubuntu.com/meta-release-lts
due to a centralized Firewall, leading to the very confusing output of "no new release found" even though it did not even look, since the request was blocked by firewall.

Since i was not fully familiar with the network structure here, it took me some time to make sense out of this message. I would suggest that the do-release-upgrade script should check if it can reach the registered meta-release servers and then provides a useful output like "Unable to reach Meta-Release server http://changelogs.ubuntu.com/meta-release-lts".

This enhancement would be very much appreciated :-)

Regards,

Dennis