Yum install on client servers of Red Hat Satellite 6 fails with TypeError: expected string or buffer.

Issue

• # yum install on client servers of Satellite Server fails with the below error:

File "/usr/bin/yum", line 29, in <module>
    yummain.user_main(sys.argv[1:], exit_code=True)
  File "/usr/share/yum-cli/yummain.py", line 375, in user_main
    errcode = main(args)
  File "/usr/share/yum-cli/yummain.py", line 184, in main
    result, resultmsgs = base.doCommands()
  File "/usr/share/yum-cli/cli.py", line 585, in doCommands
    return self.yum_cli_commands[self.basecmd].doCommand(self, self.basecmd, self.extcmds)
  File "/usr/share/yum-cli/yumcommands.py", line 1068, in doCommand
    return base.installGroups(extcmds)
  File "/usr/share/yum-cli/cli.py", line 2083, in installGroups
    groups = self.comps.return_groups(group_string)
  File "/usr/lib/python2.7/site-packages/yum/comps.py", line 663, in return_groups
    if match(name):
TypeError: expected string or buffer