I was trying to install a few packages on a compute node using yum, when I encountered the following problem:- “IOError: <urlopen error unknown url type: media>” Here is how it happened: [root@localhost yum.repos.d]# yum install opensm Loading “rhnplugin” plugin Loading “security” plugin Loading “installonlyn” plugin This system is not registered with RHN. RHN support will be disabled. Setting up Install Process Setting up repositories rhel51 100% |=========================| 1.3 kB 00:00 Reading repository metadata in from local files primary.xml.gz 100% |=========================| 780 kB 00:00 ################################################## 2857/2857 Parsing package install arguments Resolving Dependencies –> Populating transaction set ...