blacklist mirrors?

[Tom Horsley]

I was just poking around in the available yum plugins and I
didn't see one for blacklisting mirrors. Is there something
that will allow me to do that, and I just didn't recognize
it from the description?

I'm basically ready to give up on mirrors.liberty.edu since
yum keeps trying to use it, timing out, and picking a different
mirror. I'd like to tell it to stop wasting time ever
trying that particular mirror (don't know if it is a problem
with that mirror or just the path from here to there).