CentOS is dead
Red Hat has finally pulled the plug on the CentOS
Announcement: CentOS Linux 8 is EOL of December 31st 2021
CentOS which has been backbone of all the major servers, there are alternatives now out there such as Rocky Linux and Alma Linux which claim 1:1 binary compatibility with RHEL
If you are a desktop user such as me, its better to migrate to Fedora
Also, if you are getting error such as
Failed to download metadata for repo 'appstream'
CentOS team has moved all their packages from mirrorlist.centos.org to vault.centos.org
Running below commands should solve the problem
sed -i 's/mirrorlist/#mirrorlist/g' /etc/yum.repos.d/CentOS-*
sed -i 's|#baseurl=http://mirror.centos.org|baseurl=http://vault.centos.org|g' /etc/yum.repos.d/CentOS-*