The present CeroWRT builds all assign IPv6 addresses via
      dnsmasq with the settings "ra-names,ra-stateless", which is
      supposed to make the clients use SLAAC addresses

(auto-assigned
        based on MAC address) and add this to DNS.  I noticed
      today that in the case of Windows 7 clients, the AAAA records were
      missing.  It turns out that the default is to assign random
      addresses which confuses dnsmasq (the ping to SLAAC test fails). 
      Linux clients are unaffected by this, since they default to
      SLAAC-friendly assignment.

      

      The solutions to this are one of:

      

      1. Run "netsh interface ipv6 set global
      randomizeidentifiers=disabled" on each Windows 7 client to force
      them to use SLAAC.

      2. Modify /etc/dnsmasq.conf to use "ra-names,slaac" in place of
      "ra-names,ra-stateless".  This means that all clients get SLAAC
      and DHCPv6 addresses, and the DHCPv6 address gets added to DNS
      even if the SLAAC address is unpingable.  For machines with
      pingable SLAAC addresses, both type of address are present.

      

      Hope this helps anyone else that was confused by that...

-- 
Robert Bradley