[kwlug-disc] VPN Traffic

[Chris Frey]

On Sun, Aug 15, 2021 at 07:42:45PM -0400, Gordon Dey wrote:
> I modified the configuration to one of a split tunnel, so that I only
> route traffic of the vpn tunnel if the destination address matches the
> remote network range. That broke my remote name lookup, but I have a
> small set of remote hosts that I need, so I added them to the /etc/hosts
> file and called it a day.

You can use a local instance of dnsmasq to finely control how your
DNS is handled.  For example:

Assume:
	your machine's IP is		192.168.0.10
	your local gateway's IP is	192.168.0.1
	your VPN's DNS server is	10.0.0.8

Then:
	dnsmasq --no-resolv \
		--listen-address=127.0.0.1 \
		--listen-address=192.168.0.10 \
		--server=/mydomain.com/192.168.0.1 \
		--server=/no-need-for-privacy.com/192.168.0.1 \
		--server=10.0.0.8

This causes dnsmasq to listen locally (127.0.0.1) and also serve to any
other machines on your local network if you want (via 192.168.0.10).
Update those machines /etc/resolv.conf as needed.

For *.mydomain.com and *.no-need-for-privacy.com it will consult your
local gateway, which will likely consult your ISP or google depending
on your gateway's config.  It will also "know" about everything in
your /etc/hosts and serve them up locally and to your local network,
so that a single /etc/hosts becomes a mini local DNS server.  For
everything else, it will use 10.0.0.8 for DNS lookups.

- Chris