I’m not really in the mood to install Gentoo at the moment (though I’ve enjoyed Gentoo in years long past). Can I just switch to Unity or other Ubuntu 16.04 LTS desktop and keep on chugging on my PPC Mac mini for two more years?
The ubuntu-support-status utility doesn’t seem to provide any valid information.
Thanks for any advice!
Here’s a server ISO:
http://cdimage.ubuntu.com/releases/16.04.5/release/ubuntu-16.04.5-server-powerpc.iso
I can’t seem to find a desktop ISO for 16.04 powerpc. Just uncheck all the server software when you get to the software selection menu in the installer. Once Ubuntu has finished installing, install the ubuntu-desktop package.
Thanks, code_exec. Re-installing Ubuntu will be much quicker than installing Gentoo, but I don’t see why I couldn’t continue to get updates for most of the 16.04 software that’s currently installed (and up to date) under MATE. Obviously the MATE desktop will not be supported after April this year, but why can’t I just switch to an Ubuntu-supported desktop environment on my existing system (and maybe another package or two that might be specific to MATE only) and continue to get updates?
It’s strange that LTS versions of Ubuntu flavours such as Lubuntu and Ubuntu MATE only get three years of support, whereas standard Ubuntu desktop, Ubuntu Server, and Ubuntu Core get 10 years of support.
For the last couple of months, I have been prompted to update to 18.04 when I use the system updater. What would happen if I clicked yes? As far as I know, 18.04 does not exist for a powerpc device…
That’s my understanding too. I’m planning to try to substitute some Ubuntu 16.04 LTS repositories and limp along until its LTS support runs out. Then I’ll probably switch to Gentoo, rather than some form of BSD. I’ve had very good results with Gentoo on x86 in years past, but it’s a bit of work to learn and setup and I’m a bit rusty as a Gentoo admin nowadays!
There will soon not be much left to choose-from (MATE will be the next to drop off this list, come April): Click here for the Current Distrowatch PowerPC Search Results
I don’t know why exactly the software updater is notifying you of a PowerPC 18.04 update, considering there aren’t even PowerPC packages in 18.04:
Yup--I get it on my ppc Mac mini too. It's the "Software Updater" that runs automatically or it can be launched from the Applications>>System menu(???-don't have my mini in front of me, ATM). I have no idea what would happen if one accepted the invitation to upgrade to 18.04 either. I don't advise clicking to find out. 
For anyone who is interested in making a switch to Gentoo, when necessary, I'd like to plug the Gentoo forum and wiki resources as being excellent. If you're reading this on a MATE system that you've setup and enjoyed, you can do Gentoo too! It will take more effort than MATE, but you'll learn so much more about Linux OSes in return. (Sadly, I've forgotten most of it in the last 15+ years and become a lazy Linux self-admin.)
It's really a shame that support for my ppc mini is winding-down. It ran 24/7 for many, many years as both a media server (satellite 4DTV firewire and Ku band digital HD video recorder) and shorewall firewall. Most of my computers have expired into the computer boneyard since I bought this mini new 14 years ago (right from Apple as an Apple developer) but it's still running like a top. Based on my study of its architecture, it's immune to Spectre and Meltdown vulnerabilities too. It's a bit slow to boot MATE, but once it's up and running, it performs most PC sorts of activities with quite usable speed, IMHO.
I did the ubuntu-support-status check yesterday on my 16.04 Mate PPC Powerbook. It said that nearly all of my packages were unsupported. Is this now the end of support do you think?
Correction, when I apt updated and apt upgraded a few upgrades were installed so there is still some support for the moment...