[SOLVED] Device mapper error when creating zpool

lenhuppe · 2022-09-11 23:51:28

I am running Arch on a mirrored OpenZFS pool. Since grub requires an ESP I have to partition my drives. Therefore my zfs pool sits on partitions rather than on full disks.
I had been passing the two partition UUIDs to zpool during installation with no issues. Now I am getting a device mapper error when I try to create a new pool:

cannot use '/dev/mapper/': must be a block device or regular file

I tried using device ids from /dev/disk/by-id but I got the same error.

If I use the /dev/sd?? designation it works fine.

Last edited by lenhuppe (2022-09-15 02:19:53)

lenhuppe · 2022-09-15 02:19:27

The solution for me was to switch back to using the zpool cache, and create my zpool by disk id.

Have a look here: https://wiki.archlinux.org/title/Instal … nux_on_ZFS

Always use id names when working with ZFS, otherwise import errors will occur.

And look here: https://wiki.archlinux.org/title/ZFS

For ZFS to live by its "zero administration" namesake, zfs-import-cache.service must be enabled to import the pools

The export & import process allows me to configure zfs to find my pools by partuuid which was my original intent.

In addition I set the import path in both /etc/default/grub and /etc/default//zfs.

Why zpool-create stopped working with UUIDs I don't know.

Last edited by lenhuppe (2022-09-15 16:57:34)

Arch Linux

#1 2022-09-11 23:51:28

[SOLVED] Device mapper error when creating zpool

#2 2022-09-15 02:19:27

Re: [SOLVED] Device mapper error when creating zpool

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