[Bug 1092691] Re: A way to disable AAAA lookups in the resolver (again)

[Carlo Wood]

I have the same problem. After trying very hard to disable ipv6
completely (in order to get rid of EXTREME LONG download times for
chromium git and having an ISP that does not support ipv6), my interface
*STILL* has an inet6 addr and the resolver STILL does AAAA look ups :(.

This is insane-- why is there is no way to disable ipv6?!

eth0      Link encap:Ethernet  HWaddr c8:60:00:c3:37:1c  
          inet addr:192.168.0.14  Bcast:192.168.0.255  Mask:255.255.255.0
          inet6 addr: fe80::92f9:ecc1:82d2:1d3/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:27837071 errors:0 dropped:0 overruns:0 frame:0
          TX packets:24277886 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:13897890845 (13.8 GB)  TX bytes:3590197010 (3.5 GB)

Dowloading 13.8 GB of repositories (many of them) took me two days;
should be possible in an hour.

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Title:
  A way to disable AAAA lookups in the resolver (again)

Status in glibc package in Ubuntu:
  Confirmed

Bug description:
  I like to known what's the way to disable DNS AAAA queries.
  Already have disabled all resources ipv6.

  1. Changes in grub:
  vim /etc/default/grub
      GRUB_CMDLINE_LINUX_DEFAULT="ipv6.disable=1"
  update-grub

  2. I'm using 12.04 LTS version (builtin ipv6 support)
  grep -i ipv6 /boot/config-3.2.0-24-generic
      CONFIG_IPV6=y
      CONFIG_IPV6_PRIVACY=y
      ...

  Before this i try with sysctl, but tcp6 sockets still alive.
  After grub changes this solve the question - i can disable ipv6 address and networks sockets too.

  But, internal lookups stay wrong.
  Some sites like www.caixa.gov.br are slow.

  When i sniff my connection i can see many DNS AAAA records and server fail
  Running "lynx www.caixa.gov.br"

  15:57:11.332463 IP 127.0.0.1.58734 > 127.0.0.1.53: 63741+ AAAA? www.caixa.gov.br. (34)
  15:57:16.337439 IP 127.0.0.1.58734 > 127.0.0.1.53: 63741+ AAAA? www.caixa.gov.br. (34)
  15:57:21.342488 IP 127.0.0.1.58067 > 127.0.0.1.53: 1244+ AAAA? www.caixa.gov.br.localdomain. (46)
  15:57:21.342579 IP 127.0.0.1.53 > 127.0.0.1.58067: 1244 NXDomain 0/1/0 (121)
  15:57:21.342648 IP 127.0.0.1.51657 > 127.0.0.1.53: 3236+ A? www.caixa.gov.br. (34)
  15:57:21.342723 IP 127.0.0.1.53 > 127.0.0.1.51657: 3236 1/0/0 A 200.201.161.106 (50)
  15:57:21.353289 IP 127.0.0.1.58482 > 127.0.0.1.53: 15390+ AAAA? www.caixa.gov.br. (34)
  15:57:26.358326 IP 127.0.0.1.58482 > 127.0.0.1.53: 15390+ AAAA? www.caixa.gov.br. (34)
  15:57:31.363381 IP 127.0.0.1.48398 > 127.0.0.1.53: 21648+ AAAA? www.caixa.gov.br.localdomain. (46)
  15:57:31.363487 IP 127.0.0.1.53 > 127.0.0.1.48398: 21648 NXDomain 0/1/0 (121)
  15:57:31.363560 IP 127.0.0.1.55657 > 127.0.0.1.53: 49860+ A? www.caixa.gov.br. (34)
  15:57:31.363643 IP 127.0.0.1.53 > 127.0.0.1.55657: 49860 1/0/0 A 200.201.161.106 (50)
  15:57:31.364319 IP 127.0.0.1.55431 > 127.0.0.1.53: 38110+ AAAA? www.caixa.gov.br. (34)
  15:57:36.369352 IP 127.0.0.1.55431 > 127.0.0.1.53: 38110+ AAAA? www.caixa.gov.br. (34)

  I do bind changes too
  vim /etc/default/bind9
      RESOLVCONF=no
      OPTIONS="-4 -u bind"

  vim /etc/bind/named.conf.options
          forward only;
          forwarders {
                  208.67.222.222;
                  8.8.8.8;
          };

  This dont solve AAAA requests.
  I like to known a way to prefer ipv4 queries (A) or disable ipv6 queries.

  When i'm using squid proxy the same problem occur.
  To solve this i need compile squid with --disable-ipv6.
  This works to Squid proxy, but i think that the best way is disable all DNS AAAA queries.

  This occur with lynx, wget and others.

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