[CentOS] Forcing IPv4 DNS lookups first before IPv6

Mon Apr 4 17:10:39 UTC 2011
Brunner, Brian T. <BBrunner at gai-tronics.com>

centos-bounces at centos.org wrote:
> Thank you, but unfortunately this is a different issue. These boxes do
> not run bind, they resolve their DNS queries via dedicated bind
> servers on the network. Configuring the bind servers on the network a
> different way still would not stop the IPv6 traffic I am showing in
> the TCP dump from being sent.

Things described in the bug report are

Adding 
         NETWORKING_IPV6=yes
 to /etc/sysconfig/network
 prevents the queries to root nameservers with IPv6 addresses
 timing out. 

And 

alias net-pf-10 off to /etc/modprobe.conf

Have you tried both of them?

> On 4/4/2011 11:54 AM, Stephen Harris wrote:
>> On Mon, Apr 04, 2011 at 11:34:25AM -0500, Russell Jones wrote:
>>> [root at hostname1 ~]# tcpdump -vvvvv 'port 53'
>>> tcpdump: listening on eth0, link-type EN10MB (Ethernet), capture
>>> size 96 bytes 
>>> 
>>> 11:07:24.989304 IP (tos 0x0, ttl  64, id 65039, offset 0, flags
>>> [DF], proto: UDP (17), length: 60) hostname1.59725>
>>> vdns1-hc.example.com.domain: [bad udp cksum 2bd2!]  26130+ AAAA?
>>> hostname2.example.com. (32)
>> 
>> Check https://bugzilla.redhat.com/show_bug.cgi?id=140528 and see if
>> that resolves your issue. 
>> 
> _______________________________________________
> CentOS mailing list
> CentOS at centos.org
> http://lists.centos.org/mailman/listinfo/centos



Insert spiffy .sig here:
Life is complex: it has both real and imaginary parts.

//me
*******************************************************************
This email and any files transmitted with it are confidential and
intended solely for the use of the individual or entity to whom
they are addressed. If you have received this email in error please
notify the system manager. This footnote also confirms that this
email message has been swept for the presence of computer viruses.
www.Hubbell.com - Hubbell Incorporated**