It would seem that all nodes in the cluster fail to install due to a lack of initialisation of the repos, for example:
# yum search iop
Loaded plugins: product-id, refresh-packagekit, rhnplugin, security, subscription-manager
This system is receiving updates from RHN Classic or RHN Satellite.
================================= N/S Matched: iop ===================================
xorg-x11-fonts-ethiopic.noarch : Ethiopic fonts
Name and summary matches only, use "search all" for everything.
But if we clean the systems then is systems I can then discover the required packages:
# yum clean all
Loaded plugins: product-id, refresh-packagekit, rhnplugin, security,
subscription-manager
Cleaning repos: BI_AMBARI-2.1.0-20150806_1901 IOP-4.1 IOP-UTILS-1.0 hostdb
RHEL-ha RHEL-lb RHEL-optional RHEL-supplementary
: RHEL-updates RHEL-v2vwin rhel-x86_64-server-6
Cleaning up Everything
# yum search iop
Loaded plugins: product-id, refresh-packagekit, rhnplugin, security,
subscription-manager
This system is receiving updates from RHN Classic or RHN Satellite.
--<cut>--
=============================== N/S Matched: iop =================================
xorg-x11-fonts-ethiopic.noarch : Ethiopic fonts
**iop-select.noarch : Distribution Select**
Name and summary matches only, use "search all" for everything.
After which you should find that all the installs go though without any error.