Mount point of LXC lost after power failure


Nov 1, 2020
Waldems, Germany
After power failure restarting the Proxmox server is fine, but a single LXC doesn't start.

Trying to start LXC from the servers command line

root@ems:~# pct start 106
storage 'sdb' does not exist

fdisk -l

Disk /dev/sdb: 3.64 TiB, 4000787030016 bytes, 7814037168 sectors
Disk model: WDC WD40EZRZ-00G
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Disklabel type: gpt
Disk identifier: 6CD57AAE-2A19-474F-9EDB-27921BE3513D

Device Start End Sectors Size Type
/dev/sdb1 2048 7814037134 7814035087 3.6T Linux filesystem

Looks good.

root@ems:~# ls -l /mnt/pve/sdb/images/
total 4
drwxr----- 2 root root 4096 Oct 3 23:37 106

root@ems:~# ls -l /mnt/pve/sdb/images/106
total 578312436
-rw-r----- 1 root root 2199023255552 Nov 2 09:49 vm-106-disk-0.raw

Looks good to me.

After pct rescan config file of LXC looks like this

root@ems:/etc/pve/lxc# cat /etc/pve/lxc/106.conf
arch: amd64
cores: 4
features: nesting=1
hostname: mekong
memory: 2048
mp0: sdb:106/vm-106-disk-0.raw,mp=/nextcloud_data,backup=1,size=0T
net0: name=eth0,bridge=vmbr0,firewall=1,gw=,hwaddr=9E:CA:8C:85:26:33,ip=,type=veth
onboot: 1
ostype: ubuntu
rootfs: local-lvm:vm-106-disk-0,size=20G
swap: 2048
unprivileged: 1

What irritates me is that size switched from 2t to 0T.

root@ems:/etc/pve/lxc# df -h
Filesystem Size Used Avail Use% Mounted on
/dev/sdb1 3.6T 552G 2.9T 16% /mnt/pve/sdb

What should be the next steps to fix the problem?

King regards Wolfgang

in your file : /etc/pve/lxc/106.conf
the line :
mp0: sdb:106/vm-106-disk-0.raw,mp=/nextcloud_data,backup=1,size=0T
is not understood by your hypervisor.
Try naming the volume name as defined by PVE instead of the device name, ie.
replace 'sdb' by 'local-lvm' in that line, then try to boot your container again.

Best regards,

G. Delanoy

I did solve the problem in the meantime.

But regarding your hints: This is a mount point with existing data, so I had to tell that LXC to accept it again.

>> Try naming the volume name as defined by PVE instead of the device name ...

How do I find out what the names are that are defined by PVE?

> How do I find out what the names are that are defined by PVE?

In the GUI of your Datacenter, look under 'Storage'.

Best regards,

G. Delanoy


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