upgrade 9.10->10.04 fails: 'ubuntu-minimal' can not be found anymore.

[Fionn]

Binary package hint: update-manager

root@cardassian ~ # do-release-upgrade -d
Checking for a new ubuntu release
Done Upgrade tool signature
Done Upgrade tool
Done downloading
extracting 'lucid.tar.gz'
authenticate 'lucid.tar.gz' against 'lucid.tar.gz.gpg'
tar: Removing leading `/' from member names
tar: /etc/apt/preferences: Cannot stat: No such file or directory
tar: Exiting with failure status due to previous errors

Reading cache

Checking package manager

Continue running under SSH?

This session appears to be running under ssh. It is not recommended
to perform a upgrade over ssh currently because in case of failure it
is harder to recover.

If you continue, an additional ssh daemon will be started at port
'9004'.
Do you want to continue?

Continue [yN] y

Starting additional sshd

To make recovery in case of failure easier, an additional sshd will
be started on port '9004'. If anything goes wrong with the running
ssh you can still connect to the additional one.

Reading package lists: Done
Reading state information: Done
Reading state information: Done
Reading state information: Done
Done downloading
Reading package lists: Done
Reading state information: Done
Reading state information: Done
Reading state information: Done

Updating repository information
WARNING: Failed to read mirror file

Third party sources disabled

Some third party entries in your sources.list were disabled. You can
re-enable them after the upgrade with the 'software-properties' tool
or your package manager.

Done downloading

Checking package manager
Reading package lists: Donem lucid/partner Packages: 00 ackages: 00
Reading state information: Done
Reading state information: Done
Reading state information: Done

Invalid package information

After your package information was updated the essential package
'ubuntu-minimal' can not be found anymore.
This indicates a serious error, please report this bug against the
'update-manager' package and include the files in
/var/log/dist-upgrade/ in the bug report.

Restoring original system state

Aborting
Reading package lists: Donem karmic/partner Packages: 99 ackages: 99
Reading state information: Done
Reading state information: Done
Reading state information: Done

[Michael Vogt (mvo)]

Thanks for your bugreport.

It appears this is because the mirror.hetzner.de mirror is unknown. A workaround is to use one like "de.archive.ubuntu.com".

[Fionn (fbe)]

Thanks; issue solved with your hint.

However, the error message presented in this case is pretty misleading
and should be improved.

Therefor I'd like to propose changing this item to wishlist priority and
leaving it valid until fixed.

[Ryan C. Underwood (nemesis-icequake)]

This bug makes it impossible to use apt-proxy for distribution upgrades. Since distribution upgrades are the biggest upgrade download of all this is quite a problem for sites with many workstations.

[paullus (paullus325)]

Same bug during update 10.04 to 10.10. I'm using approx as apt-proxy, and can update only when restored original sources.list.

[Jean-Baptiste Lallement (jibel)]

@paullus, there are many failure that could lead to this error, please file another report, attach the files in /var/log/dist-upgrade and subscribe me to the report. Thanks.

[deejoe (nyloco)]

Just stumbled across this bug attempting to do a hardy->lucid upgrade. I use an approx proxy.

The error message is very uninformative, so I second Fionn's suggestion above.

Why does this check the identity of the mirror in the first place--is there not a chain of gpg signatures used to verify the integrity of the components to be installed independently of the ostensible name of the archive server? If not, that seems . . . alarming.

There are several approaches possible here:

1) a more informative error message

2) informing the system administrator performing the upgrade the name of the archive host being used, that the host is unrecognized, and then querying whether to proceed or not

3) removing the check entirely

[Steven B. Reeves (solarboy)]

Same issue with upgrade to 11.04. I third Fionn's suggestion. Thank you for the fix.