[CentOS-mirror] Master mirror servers broken or overloaded ?

During the past day we've been unable to rsync to the CentOS master mirror servers. Timeouts are reported:

rsync: failed to connect to us-msync.centos.org: Connection timed out (110) rsync error: error in socket IO (code 10) at clientserver.c(98)

rsync: failed to connect to eu-msync.centos.org: Connection timed out (110) rsync error: error in socket IO (code 10) at clientserver.c(98)

Are these servers really down, or are they overwhelmed with unwarranted rsync traffic ? We run a Tier1 mirror server (mirror.fysik.dtu.dk) and therefore need to rsync relatively quickly.

Is it time that the master mirror servers become restricted to Tier1 (and maybe Tier2) ?