From: Mike N 

Fedora Core 5 - Yum update fails with a message like
  "Cannot find a baseurl for repo: core".

  After poking around, I find that the mirror finder at
http://fedora.redhat.com/download/mirrors/fedora-core-5 is down with a message.

Quote:
> We are working hard to bring fedora.redhat.com back up to its fully
operational state.
>
> Until then, please visit our BitTorrent tracker or list of mirrors if you are
trying to download Fedora Core 6.

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