hi:
   we notice some ip address can not access scientific linux servers
(web or ftp). I don't know why. for example default sl7.repo list
content below:

baseurl=http://ftp.scientificlinux.org/linux/scientific/$slreleasever/$basearch/os/

http://ftp1.scientificlinux.org/linux/scientific/$slreleasever/$basearch/os/

http://ftp2.scientificlinux.org/linux/scientific/$slreleasever/$basearch/os/

ftp://ftp.scientificlinux.org/linux/scientific/$slreleasever/$basearch/os/


but they resolve to only 1 ip address: 131.225.105.11
so some of our servers can not get yum update working with the default
configuration.
this happen about a year ago. and it seems more and more ip are banned..