Setup openvpn server in Proxmox LXC Container

Administration
1

If you try to install openvpn server to an LXC container, you will get following error:

ERROR: Cannot open TUN/TAP dev /dev/net/tun: No such file or directory (errno=2)

This is related with the design decision of unprivileged containers which can’t create device nodes.

In order to solve this problem, you should do bind-mount that device node from the host system.

Follow the steps:

  • Learn container id from Proxmox Gui (for example 102)
  • Connect your proxmox host system from ssh
  • Edit /etc/pve/lxc/102.conf as root
  • Append: lxc.mount.entry: /dev/net/tun dev/net/tun none bind,create=file
  • Save the file and run pct stop 102 and pct start 102 commands

Note: If you’re using Openvpn Access Server (for included gui) and you’re using stock Debian9 Proxmox templates, you also need to install net-tools package because start script requires ifconfig binary which is not coming with standard install anymore!