[systemd-devel] systemd-umount doesn't unmount LVM volumes

[Lennart Poettering]

On Mi, 05.06.24 09:12, Vladimir Mokrozub (mva at mfc.tambov.gov.ru) wrote:

> Hello,
>
> OS: Debian 12
> systemd: 252
>
> Could someone please explain why systemd-umount doesn't unmount LVM volumes
> by device:
>
> $ systemd-mount /dev/vg0/lv0 /mnt/lvm/
> Started unit mnt-lvm.mount for mount point: /mnt/lvm
>
> $ findmnt -n /mnt/lvm
> /mnt/lvm /dev/mapper/vg0-lv0 ext4   rw,relatime
>
> $ systemctl list-units '*.mount'
> mnt-lvm.mount loaded active mounted /mnt/lvm
>
> $ systemd-umount /dev/vg0/lv0
> $ systemd-umount /dev/mapper/vg0-lv0
> $ systemd-umount /dev/dm-0
>
> None of the above commands unmount LVM volume. They don't produce any output
> and the exit status is zero.
> On the other hand, unmounting by the mountpoint works fine:
>
> $ systemd-umount /mnt/lvm/
> Stopped unit mnt-lvm.mount for mount point: /mnt/lvm
>
> This only happens with LVM, not with regular block devices.
> Is this a bug or a feature?

Uh, LVM is simply nothing anyone here tests, it's not really where the
future is. Please reproduce with a current systemd version (i.e. 252
is two years old, an eternity in Linux), and file a bug, and maybe
someone with an interest in LVM will look into, but don't hold your breath.

Lennart

--
Lennart Poettering, Berlin