how to reduce unnecessary lots of AAAA queries?

[Chuck Anderson]

On Sat, Mar 03, 2012 at 09:24:25AM +0000, MontyRee wrote:
> surely, I don't use ipv6 and "NETWORKING_IPV6=no" was configured at /etc/sysconfig/network file.

That doesn't prevent IPv6 from being autoconfigured on an interface,
it just tells the initscripts to ignore IPv6/pretend it doesn't exist.
The kernel will still do SLAAC and RA and configure interfaces with
that information (at least link-local if there are no IPv6 routers on
the network).  To prevent SLAAC:

NETWORKING_IPV6=yes
IPV6INIT=yes
IPV6FORWARDING=no
IPV6_AUTOCONF=no
IPV6_ROUTER=no
IPV6_AUTOTUNNEL=no

To really turn off all IPv6 you can put this in /etc/sysctl.conf:

net.ipv6.conf.all.disable_ipv6 = 1
net.ipv6.conf.default.disable_ipv6 = 1
net.ipv6.conf.eth0.disable_ipv6 = 1

> How to reduce(or stop) unnecessary lots of AAAA queries?

You can't, clients can decide to query whatever they want, and they
may have other IPv6 connectivity to use AAAA responses with.  AAAA can
be queried over IPv4 just fine, just as A can be queried over IPv6.