ZFS pool unexpected name change

[David Christensen]

freebsd-questions:

I have VirtualBox on a Debian GNU/Linux machine:

2026-06-13 15:50:49 root@laalaa ~
# cat /etc/debian_version ; uname -a
11.11
Linux laalaa 5.10.0-43-amd64 #1 SMP Debian 5.10.251-5 (2026-05-15)
x86_64 GNU/Linux

2026-06-13 15:55:27 root@laalaa ~
# dpkg-query -W -f='${Version}\n' virtualbox-7.0
7.0.26-168464~Debian~bullseye


VirtualBox is running a FreeBSD virtual machine:

2026-06-13 15:43:57 toor@vf2 ~
# freebsd-version -kru
14.4-RELEASE-p5
14.4-RELEASE-p5
14.4-RELEASE-p5

2026-06-13 15:46:15 toor@vf2 ~
# uname -a
FreeBSD vf2.tracy.holgerdanske.com 14.4-RELEASE-p5 FreeBSD
14.4-RELEASE-p5 GENERIC amd64


Around FreeBSD 13.3 RELEASE, I created a virtual machine with two ZFS pools:

2024-10-20 14:29:58 toor@vf2 ~
# zpool create -f -m /altroot/vf2zpool1 vf2zpool1 gpt/vf2zpool1

2024-10-20 14:30:25 toor@vf2 ~
# zpool create -f -m /altroot/vf2zpool2 vf2zpool2 gpt/vf2zpool2


The pools worked correctly under FreeBSD 13.3-RELEASE, 13.4-RELEASE, and
13.5-RELEASE.


Since upgrading to FreeBSD 14.4-RELEASE, I am unable to import the pools:

2026-06-13 15:46:23 toor@vf2 ~
# zpool import vf2zpool1
cannot import 'vf2zpool1': no such pool available

2026-06-13 16:01:50 toor@vf2 ~
# zpool import vf2zpool2
cannot import 'vf2zpool2': more than one matching pool
import by numeric ID instead


Looking for importable pools:

2026-06-13 16:02:00 toor@vf2 ~
# zpool import
pool: vf2zpool2
id: 16370591766194553060
state: ONLINE
status: Some supported features are not enabled on the pool.
(Note that they may be intentionally disabled if the
'compatibility' property is set.)
action: The pool can be imported using its name or numeric identifier,
though
some features will not be available without an explicit 'zpool upgrade'.
config:

vf2zpool2 ONLINE
gpt/vf2zpool2 ONLINE

pool: vf2zpool2
id: 15782797086784599572
state: ONLINE
status: Some supported features are not enabled on the pool.
(Note that they may be intentionally disabled if the
'compatibility' property is set.)
action: The pool can be imported using its name or numeric identifier,
though
some features will not be available without an explicit 'zpool upgrade'.
config:

vf2zpool2 ONLINE
gpt/vf2zpool1 ONLINE


Note that both pools now have the name "vf2zpool2".


I did not purposefully rename either pool.


Why do both pools now have the same name?


David

[Dag-Erling Smørgrav]

David Christensen <dpch...@holgerdanske.com> writes:
> Around FreeBSD 13.3 RELEASE, I created a virtual machine with two ZFS

> pools: [...] Since upgrading to FreeBSD 14.4-RELEASE, I am unable to
> import the pools: [...] Note that both pools now have the name
> "vf2zpool2". [...] I did not purposefully rename either pool. Why

> do both pools now have the same name?

Most likely, at some point you tried to import both pools at once like
this:

# zpool import vf2zpool1 vf2zpool2

What this actually does is rename vf2zpool1 to vf2zpool2 and then import
it.

The fix is to import vf2zpool1 under its correct name:

# zpool import 15782797086784599572 vf2zpool1

then import vf2zpool2 as usual:

# zpool import vf2zpool2

and everything will be back to normal.

DES
--
Dag-Erling Smørgrav - d...@FreeBSD.org

[David Christensen]

Thank you for the reply. RTFM zpool-import(8), your hypothesis makes
sense -- I likely attempted to import both pools using one 'zpool
import' command, while forgetting that 'zpool import' must be done one
pool at a time:

2026-06-15 15:43:15 toor@vf2 ~
# zpool list
no pools available

2026-06-15 15:53:56 toor@vf2 ~

2026-06-15 15:54:01 toor@vf2 ~

# zpool import 15782797086784599572 vf2zpool1

2026-06-15 15:54:52 toor@vf2 ~
# zpool import vf2zpool2

2026-06-15 15:55:03 toor@vf2 ~
# zpool list
NAME SIZE ALLOC FREE CKPOINT EXPANDSZ FRAG CAP DEDUP
HEALTH ALTROOT
vf2zpool1 960M 7.36M 953M - - 3% 0% 1.00x
ONLINE -
vf2zpool2 960M 286K 960M - - 0% 0% 1.00x
ONLINE -

2026-06-15 15:55:06 toor@vf2 ~
# zpool export vf2zpool1

2026-06-15 15:55:20 toor@vf2 ~
# zpool export vf2zpool2

2026-06-15 15:55:22 toor@vf2 ~
# zpool import vf2zpool1

2026-06-15 15:55:27 toor@vf2 ~
# zpool import vf2zpool2

2026-06-15 15:55:31 toor@vf2 ~
# zpool list
NAME SIZE ALLOC FREE CKPOINT EXPANDSZ FRAG CAP DEDUP
HEALTH ALTROOT
vf2zpool1 960M 7.26M 953M - - 3% 0% 1.00x
ONLINE -
vf2zpool2 960M 226K 960M - - 0% 0% 1.00x
ONLINE -


David