“Couldn't resolve host” when installing/updating yum packages

Question

Whenever I try to install or update a package using yum, after it updates its DB these messages are shown:

Loaded plugins: langpacks, presto, refresh-packagekit, tidy-cache google64

http://download.fedora.redhat.com/pub/epel/6/i386/repodata/repomd.xml:
[Errno 14] curl#6 - "Couldn't resolve host" Trying other mirror. 

http://download.fedora.redhat.com/pub/epel/6/i386/repodata/repomd.xml:
[Errno 14] curl#6 - "Couldn't resolve host" Trying other mirror.

Error: failure: repodata/repomd.xml from mypck: [Errno 256] No more mirrors to try.

I'm running Linux 3.4.3. What could be causing this problem? How do I fix it?

Answer 1

The mirrorlist contains an invalid entry. On my Fedora installation, the error is simply informative as it goes to the next entry in the mirrorlist and completes successfully.

You can remove the error by (as root or using sudo) editing the file /etc/yum.repos.d/fedora-updates.repo. You will see the following lines:

#baseurl=http://download.fedoraproject.org/pub/fedora/linux/updates/
 $releasever/$asearch/
mirrorlist=https://mirrors.fedoraproject.org/metalink?repo=updates-released-f
 $releasever&arch=$basearch

Uncomment the baseurl line and comment out the mirrorlist line. This removes the option of getting updates from the maintained list of mirrors.

Answer 2

Seems to me that the host just does not exist:

$ host download.fedora.redhat.com
Host download.fedora.redhat.com not found: 3(NXDOMAIN)

So, either

1. wait until the host becomes available again
2. find a replacement host and update that to yum sources
3. remove the host from the sources

Note that

$ host download.fedoraproject.org
download.fedoraproject.org is an alias for wildcard.fedoraproject.org.
wildcard.fedoraproject.org has address 85.236.55.6
wildcard.fedoraproject.org has address 80.239.156.215
wildcard.fedoraproject.org has address 209.132.181.16
wildcard.fedoraproject.org has IPv6 address 2001:4178:2:1269::fed2
wildcard.fedoraproject.org has IPv6 address 2610:28:3090:3001:dead:beef:cafe:fed4

which may be what you are looking for.