Jtdcftul

I recently installed Ubuntu 18.04. I set up a VPN through the standard Settings->Network GUI. I can connect to the VPN with no problems, but when I disconnect the VPN I cannot access the internet through my web browser. I can, however, ping an internet address from a shell window.

My /etc/resolv.conf file is a symlink to /run/systemd/resolve/stub-resolv.conf.

Before I connect to the VPN, the permissions/ownership are as follows:

-rw-r--r-- 1 systemd-resolve systemd-resolve 701 Jun 20 20:28 /run/systemd/resolve/stub-resolv.conf

While I am connected to the VPN these permissions stay the same, but when I disconnect, the read permissions are dropped and the ownership changes to root:root, like this:

-rw------- 1 root root 701 Jun 20 20:31 /run/systemd/resolve/stub-resolv.conf

It seems that because of this, my web browser cannot read the resolv.conf file and thus does not know what nameserver to use

If I chmod a+r this file, I can access the internet fine, even though the ownership is still root:root.

Does anyone have any idea what is happening here and how it could be fixed without manually changing permissions of the resolv file every time I disconnect the VPN?

Update: I added a script in the /etc/network/if-post-down.d directory that just changes the permissions/ownership of the stub-resolv.conf file when the VPN disconnects.

if [ "$IFACE" = ppp0 ]; then

    chmod a+r /run/systemd/resolve/stub-resolv.conf

    chown systemd-resolve:systemd-resolve /run/systemd/resolve/stub-resolv.conf

fi

That seems to work for now.

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.

A possible fix for some, seems to be to install the following:

sudo apt install resolvconf

See :

• https://bugs.launchpad.net/ubuntu/+source/network-manager/+bug/1778946