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Description of problem:
A call to getaddrinfo() using glibc x86_64 results in duplicate DNS queries for the same A-record, causing redundant network traffic and extra delay for the client application. It may also break certain DNS-based load balancing schemes

Version-Release number of selected component (if applicable):
glibc latest HEAD

How reproducible: Always

Steps to Reproduce:
1. Start tcpdump using "udp port 53"
2. wget -4 www.google.com
  
Actual results:
2 DNS A queries + 2 identical answers for "www.google.com"

Expected results:
Single DNS A query + answer

Additional info:
See glibc bug report: http://sourceware.org/bugzilla/show_bug.cgi?id=14307

*** Bug 837696 has been marked as a duplicate of this bug. ***

*** Bug 837697 has been marked as a duplicate of this bug. ***

*** Bug 837698 has been marked as a duplicate of this bug. ***

Created attachment 596504 [details]
Potential fix

Comment on attachment 596504 [details]
Potential fix

A slightly different patch was submitted to the libc-alpha mailing list: http://sourceware.org/ml/libc-alpha/2012-07/msg00057.html

It will probably be committed into SVN tomorrow (Friday)

I'm aware of that change; the RHEL 6 codebase is slightly different and in fact doesn't have the codepath where the fix is being made upstream.

*** Bug 854759 has been marked as a duplicate of this bug. ***

Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory, and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

http://rhn.redhat.com/errata/RHBA-2013-0279.html