resolv.conf permissions/ownership change after VPN disconnect
Solution 1:
I have the same issue. Maybe it is a bug. But I use NetworkManager. This solution does not work with it. The script does not run. I add my solution for it.
The NetworkManager has similar solution. The script must be added to the directory:
/etc/NetworkManager/dispatcher.d
I have added this file: "02-fix-resolv.conf.sh":
#!/bin/sh
if [ "$1" = "ppp0" -a "$2" = "vpn-up" ]; then
echo "bleeeeeee je dole" > /tmp/testjenahore.txt
chmod a+r /run/systemd/resolve/stub-resolv.conf.pppd-backup.ppp0
chown systemd-resolve:systemd-resolve /run/systemd/resolve/stub-resolv.conf.pppd-backup.ppp0
fi
It works for me. And I finded out, that the file "/run/systemd/resolve/stub-resolv.conf.pppd-backup.ppp0" has permission and owner badly. And my script fix permission and awner, when the VPN goes UP. Then it works too if the VPN goes DOWN.
Solution 2:
For network-manager-pptp or network-manager-l2tp, the actual fix is to install the resolvconf package:
sudo apt install resolvconf
The resolvconf package makes sure NetworkManager does the /etc/resolv.conf handling, extract from /etc/ppp/ip-up.d/000resolvconf :
[ -x /sbin/resolvconf ] || exit 0
[ "$USEPEERDNS" ] || exit 0
case "$6" in
nm-pptp-service-*|nm-l2tp-service-*|/org/freedesktop/NetworkManager/PPP/*)
# NetworkManager handles it
exit 0
;;
esac
See Ubuntu LP bug#1778946 for more details.