29

I cannot manage to load the tun module in my ArchLinux box. I’m trying to connect with OpenVPN, but the log says:

nm-openvpn[6662]: Note: Cannot open TUN/TAP dev /dev/net/tun: No such device (errno=19)

lsmod | grep tun

Returns nothing:

If I run:

sudo modprobe tun

It returns failure, but no error message, and lsmod still has no tun. The module seems to exist, as there is a tun.ko.gz in /lib/modules/.

I really dont know what else to try.

5 Answers 5

31

This answer is probably a bit late, but I ran into the problem, exactly as described, myself.

Running OpenVPN would produce:

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

And running tunctl would produce:

Failed to open '/dev/net/tun' : No such file or directory

And this command had no output:

lsmod | grep tun

When attempting to add the tun module via:

modprobe tun

modprobe would exit with a failure error code (1), and nothing changed.

I found an alternate way of activating the tun module via insmod. First locate the module with this command:

find /lib/modules/ -iname 'tun.ko.gz'

Then use insmod with the returned path (I only got one match), for example:

insmod /lib/modules/3.6.9-1-ARCH/kernel/drivers/net/tun.ko.gz

For me, running that command worked, and tunctl and OpenVPN worked okay afterwards.

7
  • Had this too on my raspberry pi, insmod solved it (after a reboot I can modprobe as usual)
    – unhammer
    Jul 5, 2013 at 8:05
  • Thamks! the insmod command works! Had this for an openconnect issue: Failed to open tun device: No such device May 9, 2014 at 20:05
  • Root access needed?!
    – Dr.jacky
    Dec 16, 2015 at 6:59
  • 3
    can't find /lib/modules/ -iname 'tun.ko.gz' on my Ubuntu 14.04 vps ( Mar 29, 2016 at 23:37
  • 1
    can't find it on CentOS 7 either.
    – snetch
    May 18, 2016 at 17:39
25

I ran into a similar problem when trying to run openvpn on OVH Cloud VPS, openvpn complains that cannot find TUN interface.

modprobe will always return module not found :

$ sudo modprobe tun
FATAL: Module tun not found.

Finally, I found that tun is not a module but built in kernel, so what I do to solve was created the missing dir and nod:

$ sudo mkdir /dev/net
$ sudo mknod /dev/net/tun c 10 200

And then openvpn can find and use the tun device.

To be noted that afterward, modprobe will still return an error, because tun is not a module.

$ sudo modprobe tun
FATAL: Module tun not found.
4
  • Thanks, I got this problem with OpenVPN Access Server on OVH Classic VPS after doing a dist-upgrade from Debian 7 to Debian 8. You can also do sudo chmod 600 /dev/net/tun like said in this article: wiki.vpslink.com/TUN/TAP_device_with_OpenVPN_or_Hamachi After restarting openvpn with sudo service openvpnas restart, I could connect with a client. But when I restart the Linux server, /dev/net/tun does not exist anymore. I don't know if it's normal but I added commands to /etc/rc.local so it will still work after reboot.
    – baptx
    Jun 28, 2015 at 16:34
  • Thanks. Your solution worked for my armbi port of debian squeeze running on my android mobile. I got the same error while starting OpenVPN. May 12, 2017 at 21:13
  • yes, tun is not a module.
    – MrRolling
    Jan 24, 2018 at 4:00
  • thas works for me thanx. May 12, 2018 at 19:36
2

In Arch linux installing the networkmanager-vpnc or NetworkManager-vpnc package will solve the problem

1
  • this is invalid for me, I already install that package, and reinstalling does nothing. Feb 17 at 9:20
1

Make sure you do a kernelcheck before running modprobe. See note here

An easy way is to compare the output of

uname -r

and

pacman -Q linux

If they're different, reboot. That should fix the modprobe failure.

1
  • Thank you! I'm using Manjaro and I haven't resbooted my machine since the last kernel upgrade. A simple reboot solved the problem. Jan 27, 2021 at 13:49
0

I had a problem where my /lib/modules/.../modules.alias did not contain the line

alias char-major-10-200 tunode_tunnel

So even if you've done mknod /dev/net/tun and have tun.ko somewhere in /lib/modules/..., it won't load unless modules.alias has the right incantation.

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