blag/post/google-earth-and-ipv6-dns-lookups.mdwn

   1 [[!meta title="Google Earth and IPv6 DNS lookups"]]
   2 [[!meta date="2011-01-22 13:02"]]
   3 [[!meta author="rohieb"]]
   4 [[!meta license="CC-BY-SA 3.0"]]
   5
   6 Apparently the combination of a WLAN router that blocks IPv6 DNS queries
   7 of type `AAAA` (in my case, it was a Siemens S1621-Z220-A sold as [Alice
   8 Modem 1121 WLAN][0]) and the current version of Google Earth for Linux (I am
   9 using 5.1.3533.1731 from [Medibuntu][1]) do not work well together. The
  10 problem is that the router simply throws away `AAAA` queries (or
  11 generally, any type it does not know), so the DNS query times out.
  12 However, Google Earth does not seem to fall back to IPv4 queries (type
  13 `A`) in this case, and shows a message about network connectivity errors.
  14 I don’t know if it’s Google Earth’s fault or if the underlying eglibc
  15 resolver of my Linux system does something wrong, anyhow there is a
  16 fairly well-commented [bug report][2] on Launchpad for Ubuntu Karmic and
  17 Lucid which explains the issue.
  18
  19 Anyway, I got rid of the problem by manually configuring a nameserver on
  20 my local machine (for example the nameserver(s) of your internet
  21 provider, or the ones of OpenDNS), and not using the WLAN router as a
  22 resolver. NetworkManager allows you to do this by editing a connection
  23 and choosing “Automatic DHCP (Addresses only)” on the IPv4 register tab;
  24 or you can write the settings directly to your `/etc/resolv.conf` (here
  25 for the OpenDNS servers):
  26
  27     nameserver 208.67.222.222
  28     nameserver 208.67.220.220
  29
  30 [0]: http://www.alice-wiki.de/Alice_Modem_1121_WLAN
  31 [1]: http://www.medibuntu.org/
  32 [2]: https://bugs.launchpad.net/ubuntu/+source/eglibc/+bug/417757
  33
  34 [[!tag Ubuntu workaround Alice_DSL DNS eglibc Google_Earth HanseNet IPv4
  35     IPv6 Ubuntu_Karmic Ubuntu_Lucid]]