Zfs partitions on 26.04 LTS installation

Support and Help
1

Ubuntu Version: 26.04 LTS

Desktop Environment (if applicable):
Ubuntu Desktop new installation

Problem Description:
Questions before creating a problem.
Planning to use debootstrap with a prior set up of zfs partitions. This is not covered in Ubuntu documentation.

Where is debootstrap documentation?
Any known issues or tips for doing Ubuntu install with debootstrap versus the provided auto installer?

Goal is two 4TB SSDs using zfs mirror. I have detailed set of commands for setting this up. I have tested the Ubuntu desktop auto install from Rufus USB on a 1TB SSD (no mirror or RAID) ext4 SSD and that went fine.

For the zfs installation, the manual partition capability in the auto install seems limited and may not result in efi and bpool partitions that can be mirrored and updated reliably.

Have worked up the sequence of commands to set up partitions, pools and datasets. Resulting partitions are intended to be:
p1: EFI system 1GB FAT32 GRUB UEFI boot files
p2: bpool /boot 4GB with GRUB readable zfs initrd
p3: swap 16GB (50% of memory)
p4: rpool ~3.6 TB zfs mirror

Any information is appreciated.
Dave

2

The Desktop Installer currently in use, in Manual partitioning mode, does not recognize pre-existing storage containers and data structures.

One (of several) bug reports is here

If affects LVM and your ZFS.

I like to use LVM for my installs. If I wanted to install Ubuntu in an existing LVM logical volume, it is not possible. The only way to do an LVM install of Ubuntu now is to use the erase disk and install option, wiping out whatever else is on your disk.

On the bug reports, the developers of the installer have not acted to add this support to the installer up to the present 26.04 LTS installer.

3

Dennis,

Your reply is very helpful. I found debootstrap documentation and will go that way.

Dave

4

After 3 long days of trying, could never get the efi partition set up and bootable.
Switched to Fedora (new machine so nothing list by wipefs) and was set up, updated 800+ packages, with kernel 7.1.8-200, bluetooth and wifi and rebooting just fine after 6 hrs. Much relieved.

1 Like
5

@raderdave thanks for letting us know you found a solution that works for you.

Best of luck and you are always welcome here in the future.

Topic closed.