[Dnsmasq-discuss] Questions about adding IPv6 external DNS servers to dnsmasq

[Patrick Dickey]

Hello there,

I'm running a dual-stack IPv4/IPv6 network, where my IPv6 address is
handled through a tunnel service (TunnelBroker). My router handles the
IPv6 DHCP, but doesn't hand out the DNS server information. I have an
Amahi Server running dnsmasq that handles my IPv4 DHCP and all DNS
information. Currently it's only using the IPv4 DNS Servers, as it has
never been configured with IPv6 entries.

What I need to do is set dnsmasq up so that it can handle both IPv4 and
IPv6 resolution. In the /etc/dnsmasq.conf file, I see the following
lines

# Send DHCPv6 option. Note [] around IPv6 addresses.
#dhcp-option=option6:dns-server,[1234::77],[1234::88]

# Send DHCPv6 option for namservers as the machine running 
# dnsmasq and another.
#dhcp-option=option6:dns-server,[::],[1234::88]

My questions are these:

1. If I uncomment these lines, and include the IPv6 addresses that I
want to use (OpenDNS addresses), will this get sent out to the networked
computers?
2. If I uncomment these lines, and include the IPv6 addresses, will
dnsmasq use those addresses to resolve IPv6?
3. Do I need to include my IPv6 address for the dnsmasq (Amahi) server
somewhere in either dnsmasq.conf or resolv.conf, in order to tell all
networked computers to ask it for IPv6 addresses? (I ask this, because
currently my networked computers are told to ask only the Amahi server
for IPv4 DNS resolution, so I need that to happen with IPv6 also).
4. What exactly do these two sets of configurations do, as the comment
really doesn't explain it (only tells you what you're configuring)?
5. If editing these lines won't work, will adding the entries at the
bottom of the dnsmasq.conf file do what I need?

I'm mainly asking #4 because I can't find anything online that really
explains what this option does, or how to actually *configure* your
network for IPv6 DNS resolution.

A final question is this: Will this work as I intend, or do I need to
have dnsmasq handle my IPv6 DHCP also? I can either turn off the DHCP on
my router (Cisco 2514 series), or if worse comes to worse, have the
server handle updating my tunnel also. But, I'd prefer not to do this,
in case the server is down (then at least I'll have IPv6 connectivity).

Thank you for any information, and have a great day.:)
Patrick.