Disks are constantly and automaticly unmounted

[leon_siemon]

Hello Community,

I have a problem with connecting additional storage devices to my Proxmox server. I'm running Proxmox on a mini PC with built-in SSD, but now I also wanted a small NAS solution for my home network and so I decided to install Openmediavault on the Proxmox. Since the memory of the internal SSD is not enough, I have connected an external hard drive via USB, formatted and mounted. Up to here everything works as expected.

But as soon as I start the VM with Openmediavault and let it run for a few minutes, suddenly all data is stored on the internal SSD instead of the HDD. The amount of memory on the external hard disk specified in Proxmox now corresponds to the remaining memory on the internal SSD and the data is stored directly in the /mnt/xyz directory and is not on the hard disk.

I have already rebuilt the VM several times and tested different versions. Unfortunately, there was no success.

I use version 7.2-3 of Proxmox on x86 hardware. The virtual hard disk with the OMV system is on the SSD, the HDD memory is only additionally mounted.

Since I could not find a solution to this issue online, I wanted to ask if someone can help me here.

I would be very happy about helpful contributions, thank you for any support.

With best regards

 

[dcsapak]

hi, can you post your storage config (/etc/pve/storage.cfg) your vm config (qm config ID) and the output of 'mount' and 'dmesg' ?
also, how did you format/mount the usb drives ?

 

[leon_siemon]

hi, can you post your storage config (/etc/pve/storage.cfg) your vm config (qm config ID) and the output of 'mount' and 'dmesg' ?
also, how did you format/mount the usb drives ?

Thank you for your reply,

for the content of the configs and the results of the commands please see the images below.

To format and mount the hard disk: I have deleted all the partitions of the hard disk with the help of another computer and created a new one in ext4 format with the size of the entire disk. Then I connected the disk to the proxmox computer -> rebooted -> created a directory under /mnt -> searched for the name of the disk with "lsblk" and then mounted the disk in the new directory with the command "mount /dev/sdb /mnt/usb1".
Then I added the new mount point in Proxmox under "Datacenter -> Storage" -> created a new disk for the VM on the new storage -> restarted OMV and added the storage there accordingly.

*I must correct myself, it seems that when I set up the VM again, I accidentally placed the boot disk on the external storage as well.












"dmesg" - I'm not sure what happened there, but this line appears several hundred times, only the green number in front changes. Since I would get impossible everything on a screenshot, I have now posted only one line.

 

[dcsapak]

ok i don't see /dev/sdb mounted anywhere in your mount output.

if you want the mount to be persistent across reboots, you have to either use the fstab (/etc/fstab) or a systemd-mount unit (see man systemd.mount)
also, if a storage is directly a mount point, it would be good to add the option 'is_mountpoint'
(can be done with 'pvesm set <storage> -is_mountpoint 1'
that way it only uses it when there is actually something mounted there.
if its not, the filesystem under that will be used (which is the root fs)

 

[leon_siemon]

Thank you for your help, I was not aware of all these conditions regarding mounting storage media.

The last 2h the system ran without problems. I will continue to monitor the whole thing and if it continues to run well I will mark this thread as solved.

Here is a post which helped me a lot to make the fstab entry: https://wiki.ubuntuusers.de/fstab/ (so in case someone encounters a similar problem and ends up here )