Error updating RHEL package: Cannot retrieve repository metadata for repository: rhel-x86_64-server-5

I made a local repository on my network to avoid updating the package through the internet. But my system was giving me the following error

root@linux:~ # yum update nscd
Loaded plugins: rhnplugin, security
Error: Cannot retrieve repository metadata (repomd.xml) for repository: rhel-x86_64-server-5. Please verify its path and try again

To solve this problem, I disabled the rhnplugin

root@linux:~ # vi /etc/yum/pluginconf.d/rhnplugin.conf
[main]
enabled = 0
gpgcheck = 1

# You can specify options per channel, e.g.:
#
#[rhel-i386-server-5]
#enabled = 1
#
#[some-unsigned-custom-channel]
#gpgcheck = 0