Trouble with multiboot using zfsbootmenu

OpenZFS
1

I am trying to create a multiboot setup using zfsbootmenu. My current system is booting from zfsbootmenu with an encrypted root. The zfs setup is:

NAME MOUNTPOINT
mypool none
mypool/ROOT none
mypool/ROOT/arch /
mypool/home /home

I am using a fat32 partition mounted at /efi via fstab for EFI boot. All is working as expected.

I want to clone my current system to another drive and be able to select which system to boot using zfsbootmenu.

So I:

  1. Created a new pool (mypool2) using the same command as was used to create mypool
  2. Used syncoid -r to send mypool/ROOT and mypool/home to mypool2
  3. Copied zfs properties (canmout, mountpoint, bootfs & org.zfsbootmenu:commandline) from mypool to mypool2 for the datasets where they were set

Now the pools look identical except for their name:

NAME MOUNTPOINT
mypool none
mypool/ROOT none
mypool/ROOT/arch / (bootfs set, canmount=noauto)
mypool/home /home
mypool2 none
mypool2/ROOT none
mypool2/ROOT/arch / (bootfs set, canmount=noauto)
mypool2/home /home

If I run zfs get all on each dataset in both pools and then run a diff on the outputs, the ZFS properties are also identical except for metadata that ZFS manages, specifically: creation, available, referenced, logicalreferenced, createtxg, guid, objsetid, written, snapshots_changed.

Both pools have keylocation=file:///etc/zfs/zroot.key in the parent dataset, and use the same passphrase which is in the file.

I can manually mount mypool2 using zfs load-key -L prompt mypool2, and then mount to a tmp directory.

I was expecting at this point to be able to boot into mypool2 using zfsbootmenu, however it is not working.

On boot, it asks me for the passphrase for both mypool and mypool2 and shows both pools as options in the menu. If I do CTRL-P in zfsbootmenu it shows both pools. So far so good.

When I select mypool2 to boot, it fails with:

:: running hook [zfs]
ZFS: Importing pool mypool2.
cannot import 'mypool2': no such pool available
cachefile import failed, retrying
cannot import 'mypool2': no such pool available
ERROR: ZFS: unable to import pool mypool2

I am not sure if it is related to the hostids being the same, keylocation, cachefile or something else.

I noticed that on each boot in zpool history, there is a pair of zpool import and zpool load-key commands for mypool when it succesfully boots.
However in the zpool history for mypool2 there is no load-key command when the boot fails.

So I have tried each of the following, and tested booting mypool2 after each change without success:

  1. Re-run generate-zbm and mkinitcpio -R
  2. Set keylocation=prompt on mypool2 (reverted when it didn’t work)
  3. Removed spl.spl_hostid from org.zfsbootmenu:commandline on mypool2/ROOT (reverted when it didn’t work)
  4. Set cachefile=none on mypool2 (reverted when it didn’t work)

I have been racking my brain and can’t really think of what else could be the problem. I don’t really understand the hostid stuff either.

Can anyone shed some light on what the issue could be?

Thanks!!!