Description of problem:

very often, DNS resolution fail.


Version-Release number of selected component (if applicable):
Fedora 15 up to date


How reproducible:
Every time for me, but not for every one i guess.


Steps to Reproduce:
1. try 
$ wget http://mozzila.org
--2011-08-30 16:25:35--  http://mozzila.org/
Resolving mozzila.org... failed: Name or service not known.
wget: unable to resolve host address `mozzila.org'

2. first try fail, then a second :

$ wget http://mozzila.org
--2011-08-30 16:25:37--  http://mozzila.org/
Resolving mozzila.org... 209.85.51.152
Connecting to mozzila.org|209.85.51.152|:80... connected.


The same for every sites, and every soft (wget, yum, firefox…)
  

Additional info:
Only fedora 15 is affected, its a fresh install. I never had this problem before with any distro

Here the error message of curl, maybe interesting :

$ curl www.centos.org
curl: (6) Could not resolve host: www.mozzila.org; Cannot allocate memory
(as usual, second try worked)

Notice also that if i do 
$ wget host.com
(fail)
$ curl host.com
(same host, fail too)
$ wget host.com
(succeed !)