Reinstall option offered, but does not work for i386 to x86_64 upgrade

[Nigel Stewart]

Today I upgraded a 32-bit Ubuntu 12.04 using ubuntu-16.04-beta2-desktop-amd64.iso on USB via unetbootin.
Overall, success! However, along the way I did start over due to a time-consuming delay with a package backup step that appeared to be failing for every single package. (I looked at the logs going by in the GUI installer) Wasn't sure if it was due to Ubuntu 12.04, or due to 32-bit to 64-bit, but it appeared to be failing. So I restarted and chose the reformat-and-install-fresh option for the system partition (other partitions for swap and /home) and it seems to skip this step and breeze on through the installation. At this point I can't reproduce the issue, since the 12.04 32-bit is gone forever (bye, bye!) but here is a report in case it's helpful.

1) The release of Ubuntu you are using, via 'lsb_release -rd' or System -> About Ubuntu

ubuntu-16.04-beta2-desktop-amd64.iso (GUI installer)

2) The version of the package you are using, via 'apt-cache policy pkgname' or by checking in Software Center

NA

3) What you expected to happen

Backup the system partition somehow and install 16.04.

4) What happened instead

It took a long time with what looked like failures to package each thing it came across.
The "upgrade" from Ubuntu 12.04 32-bit to 16.04 64-bit didn't look it was going to work as intended.
But I didn't wait and see, I rebooted and installed clean instead.

[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/1568284/+editstatus and add the package name in the text box next to the word Package.

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[Brian Murray (brian-murray)]

I don't think 12.04 -> 16.04 is a supported upgrade path using the Live DVD.

[Nigel Stewart (nigels)]

Fair enough if 12.04 32-bit -> 17.04 64-bit is not a supported upgrade path. However, it probably ought not be presented to the user as an option.