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Proxmox Idmapped Mount & Permission Generator

Generate the Proxmox 8.1+ idmapped mount config line, container directory prep, and host ownership verifier in one shot.

Enter your container ID, mount point details, and the host UID/GID you want to share. The tool generates the exact mpX: config line for /etc/pve/lxc/<CTID>.conf, the command to create the directory inside the container, and a host ownership check — all ready to copy.

Idmapped mounts (available in Proxmox 8.1+ on kernel 6.x) let an unprivileged container see host files as if it owns them, without editing /etc/subuid or /etc/subgid. If you need selective pass-through of specific UID/GID ranges, use the LXC UID/GID Mapping Tool instead.

Mount settings

The numeric ID of your LXC container, e.g. 101.

The mpX index in the container config, e.g. mp0.

Absolute path to the directory on the Proxmox host, e.g. /mnt/media.

Absolute path where the data should appear inside the container, e.g. /media.

Numeric UIDs that own the host data. Used to generate the ownership check. Find with stat -c "%u" /path.

Numeric GIDs that own the host data. Often matches the UID. Find with stat -c "%g" /path.

/etc/pve/lxc/<CTID>.conf 
Enter a CTID, host path, and LXC path to generate the config line.
Create directory inside container 
Enter a CTID and LXC path to generate the mkdir command.
Verify host ownership 
Enter a host path to generate the verification command.

The Permission Bridge

Step 1: Identify Host Owners

Find the numeric UID and GID that own your data on the Proxmox host:

stat -c "%u %g" /path/to/host/data

The two numbers in the output are the UID and GID. Enter them into the tool above.

Step 2: Identify Container Users

Look up the service-account ID inside the container (e.g. the user running Jellyfin or Sonarr):

pct exec CTID -- id -u username
pct exec CTID -- id -g username

The UID and GID printed here are what the container process expects to run as. The idmapped mount makes the host files appear to be owned by those IDs at the kernel level.

Compatibility Notes

  • Requires Proxmox 8.1 or newer (kernel 6.x or higher).
  • Backing filesystem must support idmapped mounts: ZFS, ext4, XFS. Some legacy network mounts (older NFS/CIFS exports) do not support this feature.
Mastering UID/GID Mapping in Proxmox LXC Containers

For the conceptual background on UID/GID mapping, default offset layouts, and when traditional lxc.idmap is still the right call.

Read the full guide