Configuration
Create device node:
mkdir /dev/net (if it doesn't exist already)
mknod /dev/net/tun c 10 200
Set permissions:
e.g. chmod 666 /dev/net/tun
There's no harm in allowing the device to be accessible by non-root users,
since CAP_NET_ADMIN is required for creating network devices or for
connecting to network devices which aren't owned by the user in question.
If you want to create persistent devices and give ownership of them to
unprivileged users, then you need the /dev/net/tun device to be usable by
those users.
from https://www.kernel.org/doc/Documentation/networking/tuntap.txt
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OpenVZ Platform
- Enter mkdir -p /dev/net
- Enter mknod /dev/net/tun c 10 200
- Enter chmod 600 /dev/net/tun
- Enter cat /dev/net/tun to test whether the TUN/TAP device is available:
- If you receive the message cat: /dev/net/tun: File descriptor in bad state your TUN/TAP device is ready for use
- If you receive the message cat: /dev/net/tun: No such device the TUN/TAP device was not successfully created: contact VPSLink Support for assistance
Please note that the TUN/TAP device will be removed if you reinstall your operating system.
from http://wiki.vpslink.com/TUN/TAP_device_with_OpenVPN_or_Hamachi