How to update Ubuntu 32-bit to 64-bit on VMware Fusion?

[VirtualMac2009]

How to update Ubuntu 16.04 LTS (Xenial Xerus) 32-bit to 64-bit on VMware Fusion 8.1.1 on Mac OS X 10.11.6 (15G31) El Capitan?

I mean, without a fresh install, but upgrading the installed version.

Thanks.

[wila]

Hi,

Ubuntu has no upgrade path from 32 bit to 64 bit.

The solution to do that actually IS a clean install.

Now that sounds bad, but it isn't as terrible as it sounds (although it might depend a bit on the complexity of your setup, if you run things like databases then it might be a bit more complex on backup/restore those)

What you normally do in such a case is to make a tarball of the user home folder.

Then also make a copy of your /etc folder (like another tar file)

To make a record of what you have installed you can use:

dpkg --get-selections > dpkg-selections.txt

Store those files somewhere safe.

Install a clean 64 bit ubuntu VM.

setup a new user, with same name as you had before, make sure that userid/groupid match.

For software you had installed you can try a dpkg --set-selections, but you might just want to install it manually unless you're comfortable with running dpkg.

Untar the user home folder over the new user you setup.

The /etc tarball should not be put back, it is for comparison only in the case something works different, to aide you in troubleshooting in case something didn't come up as you had hoped.

That's basically it and it normally even works for switching to a different linux distribution.

--

Wil

[VirtualMac2009]

Thanks Wil. I was thinking of something like this:

Upgrading ubuntu 12.04 32 bit to 64 bit [duplicate]

http://askubuntu.com/questions/409584/upgrading-ubuntu-12-04-32-bit-to-64-bit

which seems to work for Ubuntu 12.04, but for Ubuntu 16.04. Is that possible?

[wila]

Hi,

That method is basically a clean install too and is a variant of what I suggested. I'm not sure on the "preserve home" option they talk about. I think that only works IF you have your home folder on its separate partition and doubt it will work without that. Since that is not a default install configuration - I seem to recall the default is a "all in one" partition install- I'm not so sure you have a separate partition for your home folder.

You can certainly try it, but strongly suggest to take a backup before doing so as the risk of having it all wiped out sounds pretty big.

--

Wil

[vmxmr]

As wila‌ suggests, as long as you have plenty of time and enough disk space, you can shutdown your Ubuntu 32-bit virtual machine and make a backup copy of it, then try whatever you want. If it doesn't work, restore it and try something different.

A faster approach would be to take a snapshot before the upgrade. Or make one backup for the worst case scenario, and then use a snapshot. Restore the snapshot if it doesn't work and try something different. Restore the backup in a true emergency where something goes very wrong.

No matter what you do, with backups you are covered.