USB Backup confusing mount behavior

HannesJo · 29. Oktober 2019

I'm using the USB backup plugin and experiencing quite a strange behavior. I plugin the usb drive. As expected it gets mounted as "/srv/dev-disk-by-id-ata-WDC_WD40EZRZ-00WN9B0_WD-WCC4E7CKHX15-part1" and backup starts.
Have a look into the syslog, it says "systemd-aee38e127d149e5f0bfa440ad98b5fd9[7654]: Please wait, syncing....". Hmm? Usually it's labeled with the id like "systemd-WDC_WD40EZRZ-00WN9B0_WD-WCC4E7CKHX15-part1"? Not sure about that.

Output of lsblk is

Code

NAME   MAJ:MIN RM   SIZE RO TYPE MOUNTPOINT
....
sdc      8:32   0   3.7T  0 disk
└─sdc1   8:33   0   3.7T  0 part /srv/dev-disk-by-id-ata-WDC_WD40EZRZ-00WN9B0_WD-WCC4E7CKHX15-part1

After the backup has finished it tries to unmount the disk but not successfully. Syslog says "systemd-aee38e127d149e5f0bfa440ad98b5fd9[7654]: rmdir: failed to remove '/srv/aee38e127d149e5f0bfa440ad98b5fd9/': Device or resource busy". I think hmm? What actually is /srv/aee38e127d149e5f0bfa440ad98b5fd9/? My drive is /srv/dev-disk-by-id-ata-WDC_WD40EZRZ-00WN9B0_WD-WCC4E7CKHX15-part1...

Output of lsblk is now

Code

NAME   MAJ:MIN RM   SIZE RO TYPE MOUNTPOINT
....
sdc      8:32   0   3.7T  0 disk
└─sdc1   8:33   0   3.7T  0 part /srv/aee38e127d149e5f0bfa440ad98b5fd9

What is happening here? In /srv I can see both directories
drwxr-xr-x 8 root root 4096 Oct 28 23:33 aee38e127d149e5f0bfa440ad98b5fd9
drwxr-xr-x 2 root root 4096 Oct 29 12:45 dev-disk-by-id-ata-WDC_WD40EZRZ-00WN9B0_WD-WCC4E7CKHX15-part1

When I go to OMV Filesystems tab I can unmount manually but both still exist in /srv.. Actually I assume they should not be there anymore after unmounting? When I mount and unmount again using OMV menu, at least dev-disk-by-id-ata-WDC_WD40EZRZ-00WN9B0_WD-WCC4E7CKHX15-part1 is gone but aee38e127d149e5f0bfa440ad98b5fd9 is still existing in /srv.

Is that a known bug or am I missing something?

cabrio_leo · 29. Oktober 2019

Zitat von HannesJo

"systemd-aee38e127d149e5f0bfa440ad98b5fd9[7654]: rmdir: failed to remove '/srv/aee38e127d149e5f0bfa440ad98b5fd9/': Device or resource busy"

Is there any other active process "sitting" on this resource? Your CLI for example?

My experience with USB backup is that it should not be interfered while running. In that case it works quite reliable.

HannesJo · 29. Oktober 2019

No, nothing. But is switching between dev-disk-by-id-ata-WDC_WD40EZRZ-00WN9B0_WD-WCC4E7CKHX15-part1 and aee38e127d149e5f0bfa440ad98b5fd9 actually normal behavior?

cabrio_leo · 29. Oktober 2019

Zitat von HannesJo

But is switching between dev-disk-by-id-ata-WDC_WD40EZRZ-00WN9B0_WD-WCC4E7CKHX15-part1 and aee38e127d149e5f0bfa440ad98b5fd9 actually normal behavior?

Yes, I think it is! As I remember USB backup or OMV in general has used the second nomenclature in former times. Some day it was changed to the "Dev-disk-by-id" nomenclature. But USB backup is still going on the old way or at least partially. Maybe it was not completely reworked?
=> @votdev?

votdev · 29. Oktober 2019

Try to rebuild the config with

Bash

# omv-mkconf usbbackup

Jetzt mitmachen!