Standard package mirrors stop syncing updates once CentOS 7 reaches end-of-life. Redirect the package manager to the official CentOS Vault to manitain access to archived RPMs.

Backup the existing repository configuration and generate a new one pointing to the archived packages:

sudo cp /etc/yum.repos.d/CentOS-Base.repo /etc/yum.repos.d/CentOS-Base.repo.bak
sudo tee /etc/yum.repos.d/CentOS-Base.repo > /dev/null <<'REPO_CONFIG'
[vault-base]
name=CentOS 7 Archive - Base
baseurl=https://vault.centos.org/7.9.2009/os/$basearch/
enabled=1
gpgcheck=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-7

[vault-updates]
name=CentOS 7 Archive - Updates
baseurl=https://vault.centos.org/7.9.2009/updates/$basearch/
enabled=1
gpgcheck=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-7

[vault-extras]
name=CentOS 7 Archive - Extras
baseurl=https://vault.centos.org/7.9.2009/extras/$basearch/
enabled=1
gpgcheck=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-7
REPO_CONFIG

Clear outdated metadata and rebuild the local package index:

sudo yum clean all
sudo yum makecache fast

Verify connectivity by installing a lightweight utility:

sudo yum install -y tree

If specific dependencies are missing from the archive, they must be sourced manually via RPM downloads or compiled from source.

For environments requiring ongoing security patches and active maintenance, transitioning to a downstream RHEL-compatible distribution is recommended. AlmaLinux and Rocky Linux provide binary compatibility with CentOS 7 workflows while offering extended support lifecycles. Migration scripts provided by these projects automate the replacement of core packages and repository configurations, minimizing downtime during the transition.