yum update やら何やっても "Error: Cannot retrieve metalink for repository: epel. Please verify its path and try again" と言われコケる。
URLGRABBER_DEBUG=1 yum check-update 2> debug.log を叩き、debug.log の末尾あたりを見る。
debug.log
2014-10-16 13:58:10,040 attempt 1/10: https://mirrors.fedoraproject.org/metalink?repo=epel-6&arch=x86_64
INFO:urlgrabber:attempt 1/10: https://mirrors.fedoraproject.org/metalink?repo=epel-6&arch=x86_64
2014-10-16 13:58:10,041 opening local file "/var/cache/yum/x86_64/6/epel/metalink.xml.tmp" with mode wb
INFO:urlgrabber:opening local file "/var/cache/yum/x86_64/6/epel/metalink.xml.tmp" with mode wb
* About to connect() to mirrors.fedoraproject.org port 443 (#0)
* Trying 66.35.62.166... * connected
* Connected to mirrors.fedoraproject.org (66.35.62.166) port 443 (#0)
* Initializing NSS with certpath: sql:/etc/pki/nssdb
* CAfile: /etc/pki/tls/certs/ca-bundle.crt
CApath: none
* NSS error -8092
* Closing connection #0
* SSL connect error
2014-10-16 13:58:11,053 exception: [Errno 14] problem making ssl connection
INFO:urlgrabber:exception: [Errno 14] problem making ssl connection
2014-10-16 13:58:11,054 retrycode (14) not in list [-1, 2, 4, 5, 6, 7], re-raising
INFO:urlgrabber:retrycode (14) not in list [-1, 2, 4, 5, 6, 7], re-raising
Error: Cannot retrieve metalink for repository: epel. Please verify its path and try again
mirrors.fedoraproject.org に接続する時にSSL connect error が起きている。
epel リポジトリのミラー、 https://mirrors.fedoraproject.org/ のSSL証明書？が更新されちゃてるのが原因。
対応
yum update -y ca-certificates をしたらいいと思います。