Comment 23 for bug 1752411

I've run into this problem as well after upgrading my Ubuntu 17.10 installation (upgraded from 17.04) to Ubuntu 18.04 last week. My VPN script calling "openconnect" hang and no packets got forwarded. My first workaround was however to connect using nm-applet instead which worked fine (available via package network-manager-openconnect-gnome).

I found this thread after a tip from a colleague after asking for help. It would be nice to have a proper fix for users upgrading to Bionic. The timeout fix/workaround would be good enough in my opinion.

@lathiat: Thanks for the fix in avahi-daemon-check-dns.sh (wrapping "timeout" around the "host" call). I can confirm that this solves the problem for me as well.

A note from my setup:
I have *two* stuck "host -t soa local." processes launched by two different "avahi-daemon-check-dns.sh" instances. pstree says that one is launched by "vpnc-script" (launched by openconnect) and the other one is launched by "01-ifupdown" launched by "nm-dispatcher". Killing the host process started by openconnect->vpnc-script solves the problem.

And as @marvin24 said, uninstalling "ifupdown" does *not* solve the problem.

@muetze-bsw (in duplicate Bug #1772692): I can confirm that uninstalling "avahi-daemon" solves the problem. This will be my "permanent" workaround.