NetworkManager dispatcher script for disabling ipv6 when VPN is enabled.

99-vpn-ipv6-switch

#!/bin/sh
# Network Manager Dispatcher Hook:
# enables/disables ipv6 on vpn-down/vpn-up respectively
#
# Copyright (c) 2017 ooknosi
# Apache License 2.0

# Args
INTERFACE="$1"
ACTION="$2"

case $ACTION in
    vpn-up)
    # vpn connected; disable ipv6
    sysctl -w net.ipv6.conf.all.disable_ipv6=1
    ### UNCOMMENT AND EDIT BELOW IF NECESSARY
    ## add pi-hole nameserver
    #echo -n "nameserver 192.168.1.1" | /sbin/resolvconf -a "tun0.openvpn"
    ### UNCOMMENT AND EDIT ABOVE IF NECESSARY
    ;;

    vpn-down)
    # vpn disconnected; enable ipv6
    sysctl -w net.ipv6.conf.all.disable_ipv6=0
    ### UNCOMMENT AND EDIT BELOW IF NECESSARY
    ## remove pi-hole nameserver
    #/sbin/resolvconf -d "tun0.openvpn"
    ### UNCOMMENT AND EDIT ABOVE IF NECESSARY
    ;;
esac

exit 0