How To Upgrade From CentOS 7 to CentOS 8 using DNF Package Manager

This quick step by step tutorial will walk you through the upgrading process of CentOS 7 to 8 using the dnf package manager.

You will need to perform following steps with root privileges.

Installing EPEL Repository

yum -y install https://dl.fedoraproject.org/pub/epel/epel-release-latest-7.noarch.rpm

yum -y install rpmconf yum-utils

rpmconf -a

package-cleanup --leaves
package-cleanup --orphans

Installing DNF Package Manager

yum -y install dnf
dnf -y remove yum yum-metadata-parser
rm -Rf /etc/yum

dnf -y upgrade
dnf -y upgrade http://mirror.bytemark.co.uk/centos/8/BaseOS/x86_64/os/Packages/centos-release-8.0-0.1905.0.9.el8.x86_64.rpm
dnf -y upgrade https://dl.fedoraproject.org/pub/epel/epel-release-latest-8.noarch.rpm
dnf clean all

rpm -e `rpm -q kernel`
rpm -e --nodeps sysvinit-tools

Upgrading to CentOS 8

dnf -y --releasever=8 --allowerasing --setopt=deltarpm=false distro-sync
rpmconf -a
rpm -e kernel-core
dnf -y install kernel-core

Verify that grub is updated and in the right location:

ROOTDEV=`ls /dev/*da|head -1`;
echo "Detected root as $ROOTDEV..."
grub2-install $ROOTDEV

Installing Minimal Package:

dnf -y groupupdate "Core""Minimal Install"

Verify Centos version:

cat /etc/centos-release


reboot

Wrapping up

You have successfully upgraded from CentOS 7 to CentOS 8 using dnf package manager and you now have a latest release of CentOS 8.