Commands to live-upgrade CentOS Streams 8 -> 9

centos8-9.sh

# The general procedure here is adapted from the 7->8 guide here. https://www.tecmint.com/upgrade-centos-7-to-centos-8/
#
# It is a curated list of my bash history. I entered other commands so hopefully I got the right ones here.

yum upgrade
reboot
dnf install epel-release
dnf install rpmconf
dnf install yum-utils
rpmconf -a  # answer "n" to both things
package-cleanup --leaves
package-cleanup --orphans
dnf install http://mirror.stream.centos.org/9-stream/BaseOS/x86_64/os/Packages/centos-stream-repos-9.0-9.el9.noarch.rpm http://mirror.stream.centos.org/9-stream/BaseOS/x86_64/os/Packages/centos-stream-release-9.0-9.el9.noarch.rpm http://mirror.stream.centos.org/9-stream/BaseOS/x86_64/os/Packages/centos-gpg-keys-9.0-9.el9.noarch.rpm
curl -O https://dl.fedoraproject.org/pub/epel/epel-release-latest-9.noarch.rpm
curl -O https://dl.fedoraproject.org/pub/epel/epel-next-release-latest-9.noarch.rpm
rpm -Uvh *.rpm
yum update
dnf clean all
rpm -e `rpm -q kernel`
dnf -y --releasever=9 --allowerasing --setopt=deltarpm=false distro-sync
dnf clean all
reboot
rm -f /var/lib/rpm/__db*
rpm --rebuilddb
dnf -y groupupdate "Core" "Minimal Install"

just a note guys those releases dont exist on the CENTOS website anymore(9.09) ... the updated command is...

dnf install http://mirror.stream.centos.org/9-stream/BaseOS/x86_64/os/Packages/centos-stream-repos-9.0-26.el9.noarch.rpm http://mirror.stream.centos.org/9-stream/BaseOS/x86_64/os/Packages/centos-stream-release-9.0-26.el9.noarch.rpm http://mirror.stream.centos.org/9-stream/BaseOS/x86_64/os/Packages/centos-gpg-keys-9.0-26.el9.noarch.rpm