Beginning with Ubuntu 17.10, due next month, Canonical will stop building 32-bit versions of its operating system for desktop machines.
The move has been pushed by Dimitri Ledkov, a familiar name which cropped up in a Neowin article last year discussing the same topic. If you have a 32-bit machine running Ubuntu you should probably stick with Ubuntu 16.04 and start looking for a replacement device.
In the mailing list, Ledkov wrote:
“Please action the below and remove Ubuntu Desktop i386 daily-live images from the release manifest for Beta and Final milestones of 17.10 and therefore do not ship ubuntu-desktop-i386.iso artifact for 17.10 … There are no other changes requested to d-i, mini.iso, archive, or the upgrade paths.”
You may see that in the last line of that rather clunky quote, Ledkov is saying that 32-bit editions should be left intact in some cases. The proposal is stating that i386 images should stick around for core, container, and netinst, but that 32-bit should be phased out on Server and Desktop.
Another point to note is that this change will only affect the main Ubuntu release, other flavors of Ubuntu haven’t announced any similar plans. The Lubuntu and Xubuntu release, in particular, are very unlikely to cease 32-bit releases because a large part of their user base is users running very old systems.
If you want to stick with default Ubuntu on your 32-bit system, though, you should stick with Ubuntu 16.04 which will be supported until 2021 and think about buying a new machine if you don’t want to swap to another flavor.