[root@godslove etc]# yum list updates
Gathering header information file(s) from server(s)
Server: CentOS-3 - Base
retrygrab() failed for:
http://mirror.centos.org/centos/3/os/i386/headers/header.info
Executing failover method
failover: out of servers to try
Error getting file http://mirror.centos.org/centos/3/os/i386/headers/header.info
[Errno 4] IOError: <urlopen error >