CentOS 8 Error: Failed to download metadata for repo ‘appstream’

When updating packages on CentOS 8 server, I got the following error

[root@instance-20220409-2340 ~]# dnf update
Failed loading plugin "osmsplugin": No module named 'librepo'
CentOS Linux 8 - AppStream                                                                                                                                                  51  B/s |  38  B     00:00    
Error: Failed to download metadata for repo 'appstream': Cannot prepare internal mirrorlist: No URLs in mirrorlist
[root@instance-20220409-2340 ~]# 

This is because CentOS 8 have reached its End of life.

To fix the dnf error, you can change the repository baseurl to vault.centos.org

sed -i -e "s|mirrorlist=|#mirrorlist=|g" /etc/yum.repos.d/CentOS-*
sed -i -e "s|#baseurl=http://mirror.centos.org|baseurl=http://vault.centos.org|g" /etc/yum.repos.d/CentOS-*

You may need to convert CentOS 8 to one of the supported Linux distributions.

Convert CentOS 8 to CentOS 8 Stream

To convert CentOS 8 to CentOS 8 Stream, run

dnf --disablerepo '*' --enablerepo=extras swap centos-linux-repos centos-stream-repos
dnf distro-sync

C

Convert CentOS 8 to RHEL 8

RedHat provides Convert2RHEL script to convert CentOS 8 to RHEL 8. RHEL is now FREE for production up to 16 servers.