I too have been facing this issue since a few releases, and still face it on Ubuntu 19.10 (resolvconf not installed as it causes other issues):
# sudo rm /run/systemd/resolve/stub-resolv.conf.tmp
# sudo systemctl restart NetworkManager
# ls -la /etc/resolv.conf /run/systemd/resolve/ lrwxrwxrwx 1 root root 39 Dec 23 16:31 /etc/resolv.conf -> ../run/systemd/resolve/stub-resolv.conf
/run/systemd/resolve/: total 8 drwxr-xr-x 3 systemd-resolve systemd-resolve 100 Jan 14 13:01 . drwxr-xr-x 21 root root 480 Jan 14 06:59 .. drwx------ 2 systemd-resolve systemd-resolve 60 Jan 14 13:01 netif -rw-r--r-- 1 systemd-resolve systemd-resolve 613 Jan 14 13:01 resolv.conf -rw-r--r-- 1 systemd-resolve systemd-resolve 731 Jan 14 13:01 stub-resolv.conf
# nmcli connection up vpn.mydomain.com Connection successfully activated (D-Bus active path: /org/freedesktop/NetworkManager/ActiveConnection/10)
/run/systemd/resolve/: total 16 drwxr-xr-x 3 systemd-resolve systemd-resolve 140 Jan 14 13:01 . drwxr-xr-x 21 root root 480 Jan 14 06:59 .. drwx------ 2 systemd-resolve systemd-resolve 60 Jan 14 13:01 netif -rw-r--r-- 1 systemd-resolve systemd-resolve 613 Jan 14 13:01 resolv.conf -rw-r--r-- 1 systemd-resolve systemd-resolve 731 Jan 14 13:01 stub-resolv.conf -rw------- 1 root root 731 Jan 14 13:01 stub-resolv.conf.pppd-backup.ppp0 -rw-r--r-- 1 root root 753 Jan 14 13:01 stub-resolv.conf.tmp
# nmcli connection down vpn.mydomain.com Connection 'vpn.mydomain.com' successfully deactivated (D-Bus active path: /org/freedesktop/NetworkManager/ActiveConnection/10)
/run/systemd/resolve/: total 12 drwxr-xr-x 3 systemd-resolve systemd-resolve 120 Jan 14 13:02 . drwxr-xr-x 21 root root 480 Jan 14 06:59 .. drwx------ 2 systemd-resolve systemd-resolve 60 Jan 14 13:01 netif -rw-r--r-- 1 systemd-resolve systemd-resolve 613 Jan 14 13:01 resolv.conf -rw------- 1 root root 731 Jan 14 13:01 stub-resolv.conf -rw-r--r-- 1 root root 753 Jan 14 13:01 stub-resolv.conf.tmp
# cat /etc/resolv.conf cat: /etc/resolv.conf: Permission denied
# ping -c1 www.google.com ping: www.google.com: Name or service not known
# sudo chmod a+r /etc/resolv.conf
# ping -c1 www.google.com PING www.google.com (216.58.201.228) 56(84) bytes of data. 64 bytes from par10s33-in-f4.1e100.net (216.58.201.228): icmp_seq=1 ttl=56 time=4.52 ms
--- www.google.com ping statistics --- 1 packets transmitted, 1 received, 0% packet loss, time 0ms rtt min/avg/max/mdev = 4.522/4.522/4.522/0.000 ms
My work-around is to disable both up and down 0000usepeerdns scripts:
# sudo dpkg-divert --divert /etc/ppp/ip-down.d/0000usepeerdns.bak --rename /etc/ppp/ip-down.d/0000usepeerdns
# sudo dpkg-divert --divert /etc/ppp/ip-up.d/0000usepeerdns.bak --rename /etc/ppp/ip-up.d/0000usepeerdns
I too have been facing this issue since a few releases, and still face it on Ubuntu 19.10 (resolvconf not installed as it causes other issues):
# sudo rm /run/systemd/ resolve/ stub-resolv. conf.tmp
# sudo systemctl restart NetworkManager
# ls -la /etc/resolv.conf /run/systemd/ resolve/ systemd/ resolve/ stub-resolv. conf
lrwxrwxrwx 1 root root 39 Dec 23 16:31 /etc/resolv.conf -> ../run/
/run/systemd/ resolve/ :
total 8
drwxr-xr-x 3 systemd-resolve systemd-resolve 100 Jan 14 13:01 .
drwxr-xr-x 21 root root 480 Jan 14 06:59 ..
drwx------ 2 systemd-resolve systemd-resolve 60 Jan 14 13:01 netif
-rw-r--r-- 1 systemd-resolve systemd-resolve 613 Jan 14 13:01 resolv.conf
-rw-r--r-- 1 systemd-resolve systemd-resolve 731 Jan 14 13:01 stub-resolv.conf
# nmcli connection up vpn.mydomain.com p/NetworkManage r/ActiveConnect ion/10)
Connection successfully activated (D-Bus active path: /org/freedeskto
# ls -la /etc/resolv.conf /run/systemd/ resolve/ systemd/ resolve/ stub-resolv. conf
lrwxrwxrwx 1 root root 39 Dec 23 16:31 /etc/resolv.conf -> ../run/
/run/systemd/ resolve/ : conf.pppd- backup. ppp0 conf.tmp
total 16
drwxr-xr-x 3 systemd-resolve systemd-resolve 140 Jan 14 13:01 .
drwxr-xr-x 21 root root 480 Jan 14 06:59 ..
drwx------ 2 systemd-resolve systemd-resolve 60 Jan 14 13:01 netif
-rw-r--r-- 1 systemd-resolve systemd-resolve 613 Jan 14 13:01 resolv.conf
-rw-r--r-- 1 systemd-resolve systemd-resolve 731 Jan 14 13:01 stub-resolv.conf
-rw------- 1 root root 731 Jan 14 13:01 stub-resolv.
-rw-r--r-- 1 root root 753 Jan 14 13:01 stub-resolv.
# nmcli connection down vpn.mydomain.com p/NetworkManage r/ActiveConnect ion/10)
Connection 'vpn.mydomain.com' successfully deactivated (D-Bus active path: /org/freedeskto
# ls -la /etc/resolv.conf /run/systemd/ resolve/ systemd/ resolve/ stub-resolv. conf
lrwxrwxrwx 1 root root 39 Dec 23 16:31 /etc/resolv.conf -> ../run/
/run/systemd/ resolve/ : conf.tmp
total 12
drwxr-xr-x 3 systemd-resolve systemd-resolve 120 Jan 14 13:02 .
drwxr-xr-x 21 root root 480 Jan 14 06:59 ..
drwx------ 2 systemd-resolve systemd-resolve 60 Jan 14 13:01 netif
-rw-r--r-- 1 systemd-resolve systemd-resolve 613 Jan 14 13:01 resolv.conf
-rw------- 1 root root 731 Jan 14 13:01 stub-resolv.conf
-rw-r--r-- 1 root root 753 Jan 14 13:01 stub-resolv.
# cat /etc/resolv.conf
cat: /etc/resolv.conf: Permission denied
# ping -c1 www.google.com
ping: www.google.com: Name or service not known
# sudo chmod a+r /etc/resolv.conf
# ping -c1 www.google.com in-f4.1e100. net (216.58.201.228): icmp_seq=1 ttl=56 time=4.52 ms
PING www.google.com (216.58.201.228) 56(84) bytes of data.
64 bytes from par10s33-
--- www.google.com ping statistics --- 522/4.522/ 0.000 ms
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 4.522/4.
My work-around is to disable both up and down 0000usepeerdns scripts:
# sudo dpkg-divert --divert /etc/ppp/ ip-down. d/0000usepeerdn s.bak --rename /etc/ppp/ ip-down. d/0000usepeerdn s
# sudo dpkg-divert --divert /etc/ppp/ ip-up.d/ 0000usepeerdns. bak --rename /etc/ppp/ ip-up.d/ 0000usepeerdns