[systemd-devel] systemd 210 - mount/umount/remount

[Michael Hirmke]

Hi Lennart,

>On Fri, 14.10.16 12:06, Michael Hirmke (camping at mike.franken.de) wrote:

>> 1. How can I prevent systemd from mounting a manually unmounted
>>    partition? The partiton should be mounted automatically during system
>>    start, though.

>There were some changes related to this in more recent versions of
>systemd. Consider upgrading, 210 is pretty ancient.

the distribution I use is openSuSE Leap 42.1 which comes with this
version of systemd. Installing a newer version would break a lot of
things so I tried to avoid this. But Leap 42.2 is on its way and it
contains a much newer version of systemd. So I hope they get it finished
soon.

>That said, if you don't want systemd to mount the thing, consider
>removing it from /etc/fstab (or setting "noauto" on the entry there)
>and issuing "systemctl daemon-reload".

This would mean, that it isn't mounted on system start, which is
necessary for this machine.

>In never systemd versions you can also take BSD file lock on the
>top-level device node in order to block udev from refreshing the
>device and generating events for it.

That sounds interesting, but I never heard of this feature.
Where can I get more information about it?

>> 2. If I would switch from mount/umount to pure systemd behaviour for
>>    mounting and unmounting partitons in my script, would a command like
>>    "systemctl stop|start /var/backup" be sufficient?
>>    And how would a remount command (for read only or read write) look
>>    like?

>"systemctl stop /var/backup" is probably not going to suffice. If you
>modify your partition table/disk image during runtime this means the
>device will vanish from and return to systemd's view as the accesses
>are serialized. Whenever the device pops up again systemd might
>requeue the jobs declared in /etc/fstab via the "auto" mount option.

I tried it and it behaved exactly as you described above. Therefore it
was not useful for my purpose.
I then added a mask command before my umount and an unmask command after
remounting the partition. Dirty, but working solution.

>Lennart

Thx and bye.
Michael.
-- 
Michael Hirmke