#!/bin/bash -e ifname="$1" ifaddr="$2" ifmask="$3" echo "*** Configuring tun $ifname with addr $ifaddr/$ifmask" if grep "$ifname" /proc/net/dev > /dev/null; then ip tuntap del name "$ifname" mode tun fi ip tuntap add name "$ifname" mode tun ip addr add "$ifaddr/$ifmask" dev "$ifname" ip link set "$ifname" up echo "*** done configuring tun interface $ifname"