Broken SplitDNS resolution in networ-manager VPN after disconnect and reconnect

[Giovanni Panozzo]

Release: Ubuntu 16.04.2 LTS
network-manager package version: 1.2.6-0ubuntu0.16.04.1

I'm using Ubuntu Desktop 16.04 x64 and I have some VPN (OpenVPN and Cisco vpnc) connections defined. In all these connections I use both split tunnel and split dns.

When I connect to a remote VPN server, my Ubuntu client correctly resolves DNS names in zones pushed by the remode server using the remote DNS server.
For example: the remote VPN server pushes to the client "DNS resolver is 192.168.10.1 for domain "vpndom.net"", then "host srv1.vpndom.net" is correctly resolved bu 192.168.10.1 and I get 192.168.10.7.

After disconnecting and reconnecting to the VPN server, my Ubuntu client is no longer able to resolve DNS names in zones pushed by the VPN servers: "host srv1.vpndom.net" returns host not found.

As a temporary solution, I downgraded netowrk manager to 1.2.2-0ubuntu0.16.04.4 and all is working fine. So I think the problem is in network-manager 1.2.6-0ubuntu0.16.04.1

As a workaround, with the connected VPN tunnel, I just "sudo killall dnsmasq": NetworkManager will then restart dnsmasq passing it all correct DNSes. There is no need to disconnect from the vpn.

[Giovanni Panozzo (giox069)]

Ubuntu 17.04 seems to work very well with my split DNS setup. Also with multiple VPN connections at the same time.

[Giovanni Panozzo (giox069)]

Solved with dnsmasq-base 2.75-1ubuntu0.16.04.2, thank you.