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I connect to AirVPN using OpenVPN from command line. $ sudo openvpn --config foo.ovpn I'm using ubuntu 16 with the latest version of OpenVPN. Sometimes OpenVPN creates a tun0 interface on 10.4.0.1 and other times it's 10.7.0.1. I think I've seen it on other 10.*.0.1 addresses before, but I'm not positive at the moment. 1. How are these addresses automatically assigned? 2. My /etc/resolv.conf is using the 10.4.0.1 nameserver. Should I change my nameserver to 10.7.0.1 when openvpn creates tun0 on that address? Should the nameserver in resolv.conf always match the tun0 address? 3. Can I manually force all future ovpn connections to use 10.4.0.1? If yes, how? Thanks