Not loading "rhnplugin" plugin, as it is disabled

After subscribing to the Red Hat Subscription by doing a

# subscription-manager register

After that I did a

# yum clean all
# yum repolist -v
..... 
Not loading "rhnplugin" plugin, as it is disabled
.....

Finally, I did a

# subscription-manager list --available

Select the right pool

# subscription-manager subscribe --pool=xxxxxxxxxxxxxxxxxxxxxx

If it still does not work, go for the RHN Classic

# rhn_register

You can check whether it works by

# yum -d10 repolist

Repo-id      : rhel-x86_64-server-6
Repo-name    : Red Hat Enterprise Linux Server (v. 6 for 64-bit x86_64)
Repo-updated : Tue Nov 10 21:10:32 2015
Repo-pkgs    : 16,298
Repo-size    : 28 G
Repo-baseurl : https://xmlrpc.rhn.redhat.com/XMLRPC/GET-REQ/rhel-x86_64-server-6
Repo-expire  : 21,600 second(s) (last: Thu Nov 12 09:19:23 2015)
Repo-exclude : ibutils-libs*
Repo-excluded: 12