Bind mount one path r/w to multiple containers

Hello everyone,

Currently I’m using Lxd via snapd on Debian Buster to containerize my home server. And… I’m new to Lxd / Lxc.

I have 4 containers with different services (nextcloud, samba, tvheadend, lms).

The ID mapping (uid/gid) for the containers are isolated from the host and from each other.

At the moment my data is stored on a sepperate Nas (Samba). My lxd host is accessing the Nas via cifs mounts (sometimes the same shares are mounted to a different path because I need to chown them to match the respective container user uids/gids for r/w).

I have configured different devices and bind mounted them to my containers.

That seems to work great for my usecases.

However, I want to save energy and I would like to use the nas hard disks in my server in the future. The described cifs mounts will then be omitted.

I’m worried about how I can ensure r/w access for multiple containers to the same path on the host in the future.

Is it even possible?
Is there a best practice or a better strategy?

I looking forward to your answers.

Best regards


I implemented support for this which will be in LXD 3.16 so long as you have an Ubuntu kernel that’s 5.0 or higher (has shiftfs support).

With such a system, you can do:

lxc config device add CONTAINER DEVICE disk path=/container/path source=/host/path shift=true

And it will show up in the container with the same visible uid/gid as you would see on the host, allowing for it to be passed to multiple isolated containers and show the same uid/gid on all of them.

Good morning Stephané,

I’m glad to here this :slight_smile: …when do you plan to publish 3.16?

At the moment I’m on Debian Buster, so I hope there will be support for Debian asap too.

Meanwhile, maybe there is a chance to do this with bindfs, like with different Samba shares?

And a norther Questions, there is one container with uid > 1300000. When I try chown I’ll get: I valid user, when I try to mount I’ll get: bad option.

The container is configured for isolated idmap like the others three…


root 1000000:1000000000

lxd 1000000:1000000000

Best regards