Problem: this system is not registered with RHN in red hat is because RHN is not registered in red hat.
Solution 1:
(Assuming you have installed Yum and the network is smooth) change the yum source, that is, change the/etc/yum. Repos. d/rhel-debuginfo.repo file.
Enter the/etc/yum. Repos. d/directory, and enter wget secret in the terminal.
Solution 2:
1. Uninstall the yum component that comes with RedHat
[Root @ localhost ~] # Rpm-Qa | grep Yum | xargs rpm-e -- nodeps
2. Install centos Yum package
32-bit
# Wget http://centos.ustc.edu.cn/centos/5/ OS /i386/CentOS/yum-metadata-parser-1.1.2-3.el5.centos.i386.rpm
# Wget http://centos.ustc.edu.cn/centos/5/ OS /i386/CentOS/yum-fastestmirror-1.1.16-16.el5.centos.noarch.rpm
# Wget http://centos.ustc.edu.cn/centos/5/ OS /i386/CentOS/yum-3.2.22-37.el5.centos.noarch.rpm
64-bit
# Wget http://centos.ustc.edu.cn/centos/5/ OS /x86_64/CentOS/yum-metadata-parser-1.1.2-3.el5.centos.x86_64.rpm
# Wget http://centos.ustc.edu.cn/centos/5/ OS /x86_64/CentOS/yum-fastestmirror-1.1.16-21.el5.centos.noarch.rpm
# Wget http://centos.ustc.edu.cn/centos/5/ OS /x86_64/CentOS/yum-3.2.22-39.el5.centos.noarch.rpm
[Root @ localhost ~] # Rpm-IVH *. rpm
3. Download the update source and store it in the system directory [root @ localhost ~] # Wget http://docs.linuxtone.org/soft/lemp/CentOS-Base.repo
[Root @ localhost ~] # Mv CentOS-Base.repo/etc/yum. Repos. d/CentOS-Base.repo
4. Generate Cache
[Root @ localhost ~] # Yum makecache