On: Linux boot partitions and how to set them up

[yjftsjthsd-h]

Interestingly, GRUB actually supports ZFS; it has the dubious distinction of being the only extant implementation of ZFS that's GPL licensed, but... probably because of that... it's separate from the main OpenZFS implementation is extremely feature-poor. This results in fun things like Ubuntu's root-on-ZFS layout creating 2 pools; a boot pool (bpool) that GRUB can read, and a root pool (rpool) with the OS. It's not that complicated, but it's not nice.

[cryptonector → yjftsjthsd-h]

That's because in the mid-oughts Solaris used GRUB for booting.

It's really nice because you get to boot from multiple datasets in the same pool so upgrades and downgrades can be very smooth.

[Volundr → yjftsjthsd-h]

Interesting. I've never really wanted on boot on ZFS, and I definitely don't see the point if I'd need a dedicated pool for it.

[yjftsjthsd-h → Volundr]

It could be really cool; it would let you snapshot your boot filesystem and roll back to a previous configuration.

...I say, as someone who does in fact leave my boot filesystems on VFAT:)

[vetinari → yjftsjthsd-h]

Ubuntu did snapshot the bpool; unfortunately, it did a poor job of garbage collecting the snapshots. Meaning that eventually you would have failing kernel updates due to lack of space, and having to manually clean it up.

Since 22.04, zsys (the tool that did the snapshoting) is not installed by default.

[yjftsjthsd-h → vetinari]

> Since 22.04, zsys (the tool that did the snapshoting) is not installed by default.

Er, are they not snapshotting the root filesystem or ex. /home by default then?

[vetinari → yjftsjthsd-h]

No, you have to install and enable zsys yourself.

[cryptonector → Volundr]

It's a lot easier to manage one pool occupying one large partition on all the disks in the pool than it is to manage any number of partitions without pooling.