Mount an SMB share and use iGPU on an unprivileged Debian 12 LXC container in Proxmox

Feb 8, 2024

Procedure

Prerequisites:

Create an unprivileged Debian 12 LXC container.

Inside the LXC container, use the root user to create a non-root user. In this example the user is added to the sudo and docker groups after installing Docker inside the LXC container.

useradd -s /bin/bash -m -G sudo,docker ismael

Change the user password as needed.

su ismael
passwd

This user’s default UID:GID will be 1000:1000. If not, create it with:

useradd ismael -u 1000 -g 1000 -m -s /bin/bash -G sudo,docker

Take note of this UID:GID as it will be used to map the share in Proxmox. The share itself can live on another system; here an unRAID VM on the same host is used.

On the Proxmox host

Create a user that can be mapped from the host to the LXC container. Without this step, the share ends up read-only inside the LXC container.

Proxmox maps the users and groups from the host to the LXC containers starting at UID:GID=100000:100000.

The created ismael user then:

Inside the LXC container UID: 1000
Inside the host UID: 101000

Create a group on the host with GID=101000 that will own the directory created for the SMB share

groupadd -g 101000 ismael

Create the same user that will be used inside the LXC container but with the right UID:GID combination

useradd ismael -u 101000 -g 101000 -m -s /bin/bash

Make a directory for the share

mkdir /mnt/media

Change the directory’s owner to the previously created user

chown ismael:ismael /mnt/media

Modify the /etc/fstab file to mount the SMB share on the directory we created

nano /etc/fstab

Copy this line inside the nano editor for /etc/fstab (note the guest part, as this SMB share has no password set)

//192.168.0.10/media /mnt/media cifs guest,rw,uid=1000,gid=1000,file_mode=0777,dir_mode=0777 0 0

For shares that require a password:

//192.168.0.10/media /mnt/media cifs username=<username>,password=<password>,rw,uid=1000,gid=1000,file_mode=0777,dir_mode=0777 0 0

Reload the changes to /etc/fstab before mounting

systemctl daemon-reload
mount -a

Create a mountpoint in your LXC container pointing to the created share directory

pct set 104 -mp0 /mnt/media,mp=/mnt/user/media

Start the LXC container and the share is mounted in /mnt/user/media, writable by the mapped user.

iGPU

Coming soon…