Missing /dev/net/tun

[Puzzling3480]

As I was trying to create a VM on my Proxmox node, following message poped up:

kvm: -netdev type=tap,id=net0,ifname=tap102i0,script=/var/lib/qemu-server/pve-bridge,downscript=/var/lib/qemu-server/pve-bridgedown,vhost=on: could not open /dev/net/tun: No such file or directory
TASK ERROR: start failed: QEMU exited with code 1

I already had trouble creating an Dockerimage of Transmission in an LXC, because of /dev/net/tun. Never found a solution.

 

[t.lamprecht]

Is Proxmox VE set up in some virtual/containerized environment or directly installed on the host?

What's the used version/kernel, i.e., output of pveversion -v (or Web UI -> Node -> Summary -> [Package Versions] button).

Normally, this character device node is created automatically, but what happens in your setup if you try to do so manually, e.g. by executing the following creation + file permission commands as root in the Proxmox VE shell:

mknod /dev/net/tun c 10 200
chmod 0666 /dev/net/tun