PYCURL ERROR 7 - "couldn't connect to host"

[Semi]

Yum doesn't work on SL6.4, it get error and quit.
yum update
Loaded plugins: refresh-packagekit, security
http://dl.atrpms.net/el6-x86_64/atrpms/stable/repodata/repomd.xml: 
[Errno 14] PYCURL ERROR 7 - "couldn't connect to host"
Trying other mirror.
Error: Cannot retrieve repository metadata (repomd.xml) for repository: 
atrpms. Please verify its path and try again