mkstage4 VS rpi-gentoo-images

Create a "stage4" tarball using mkstage4 (this is basically just a nice wrapper around a tar command where you don't have to remember all the options)

I'm thankful for tools like mkstage4, for the record...

You'll be fine, if you are new to Gentoo maybe look into keeping system backups while you are learning using something like mkstage4 or if you want extra nerd points something like snapshots in ZFS.

Make a stage 4 tarball. Then just follow the handbook and instead of a stage 3 use your stage 4. Chroot and configure grub should be it after that.

I migrated my filesystem from a single drive into two drives, one for my home directory, and the other for everything else (/boot, /, etc.). To do that, I created tarballs of the system and extracted them to the destination drive. I decided to use a script that automates some of that process for me (https://github.com/TheChymera/mkstage4). The result is 3 tarballs: one for /boot, one for /home, and one for /, excluding the past two directories. Migration has been somewhat seamless but I had to edit a few file permissions that were messed up because of the migration.

mkstage4 has always been my goto on Gentoo. Boot from live media, create your partitions, mount, extract the tarball to the destination and chroot into the new installation for cleanup... emerge -avuDn @world for good measure.

I recently had a power failure caused by severe thunderstorms, which resulted in some screwed up partitions on my primary workstation. A blind fsck screwed up python and portage, which made the system completely unusable. Luckily, I had a stage4 tarball created with mkstage4, but it was way out of date (December 5 2021, 5.15 eries kernel). I was able to wipe (nvme-cli for NVMEs and hdparm --security-erase for the SATA SSDs) and recreate the partitions, then extracted the tarball (multi-threaded, using pbzip2), and was able to successfully chroot the install.

Make a Stage4 tarball. You can do it periodically as significant changes happen. I have restored my system from these a few times. The downside is each Stage4 is a full backup so it takes up a lot of space. I only make them periodically. I have a script that I have set to an alias to make one of these whenever I feel the need (maybe twice a year).

You can probably also just make a stage 4 tarball and then install that way. Basically you follow the guide for partitioning and once you get to stage 3 tarball you use your stage 4 instead. Then skip ahead to setting up grub and you're done.

You can take some inspiration from the shell scripts I wrote to build Gentoo Raspberry Pi images at some point: https://github.com/StephanvanSchaik/rpi-gentoo-images

I don't actively maintain this project, because a) I mostly needed these images for a project that spanned a few weeks and b) I know of no active users, but the shell scripts could be useful to anyone interested: https://github.com/StephanvanSchaik/rpi-gentoo-images and you can open issues if you encounter any, and I will probably have time to look at them.