How to Migrate from Centos 8 to Alma Linux 8

Linux

Migrate to AlmaLinux from Centos 8

AlmaLinux is a free and open source Linux distribution, created originally by CloudLinux to provide a community-supported, production-grade enterprise operating system that is binary-compatible with Red Hat Enterprise Linux. The first stable release of AlmaLinux was published on March 30, 2021.

CentOS 8 Linux will be not supported by the end of the year 2021 and if you want to migrate it to AlmaLinux 8,you can follow this article.

In this guide, we will show you how to migrate to Alma Linux from centos 8

Note: Please make sure take important data backup before migrating to Alma Linux. if anything goes wrong during migration,you can restore from backup.

Step 1: update centos 8 system

Before updating, will check the centos version

[lampblogs@localhost ~]$ cat /etc/redhat-release
CentOS Linux release 8.0.1905 (Core)

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update all the packages to the latest version with following command.

sudo dnf update

once packages are updated Reboot your system 

sudo reboot

Now check the version

[lampblogs@localhost ~]$ cat /etc/redhat-release
CentOS Linux release 8.4.2105

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Step 2: download and run AlmaLinux script

To download the AlmaLinux migration script, run the following command.

curl -O https://raw.githubusercontent.com/AlmaLinux/almalinux-deploy/master/almalinux-deploy.sh

Next set the permissions to execute the script

sudo chmod +x almalinux-deploy.sh

Now run the script as below

sudo bash almalinux-deploy.sh

script runs few system checks.It then goes ahead to uninstall,reinstall,upgrade some packages to synchronize them with the latest release of AlmaLinux.

output:

Check root privileges                                                 OK
Check centos-8.x86_64 is supported                                    OK
Download RPM-GPG-KEY-AlmaLinux                                        OK
Import RPM-GPG-KEY-AlmaLinux to RPM DB                                OK
Download almalinux-release package                                    OK
Verify almalinux-release package                                      OK
Your OS is supported                                                  OK
Remove OS specific rpm packages                                       OK
Verifying...                          ########################################
Preparing...                          ########################################
Updating / installing...
almalinux-release-8.4-3.el8           ########################################
Install almalinux-release package                                     OK
Remove centos-backgrounds centos-logos centos-indexhtml packages      OK

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this process takes some time to complete. once it is completed it will display the at the end as shown below.

  xz-libs-5.2.4-3.el8.x86_64
  yajl-2.1.0-10.el8.x86_64
  yelp-2:3.28.1-3.el8.x86_64
  yelp-libs-2:3.28.1-3.el8.x86_64
  yelp-tools-3.28.0-3.el8.noarch
  yelp-xsl-3.28.0-2.el8.noarch
  yum-4.4.2-11.el8.noarch
  zenity-3.28.1-1.el8.x86_64
  zip-3.0-23.el8.x86_64
  zlib-1.2.11-17.el8.x86_64
Complete!
Run dnf distro-sync -y                                                OK
Restoring of alternatives is done                                     OK
Generating grub configuration file ...
File descriptor 5 (/var/log/almalinux-deploy.debug.log) leaked on vgs invocation. Parent PID 104330: /usr/sbin/grub2-probe
File descriptor 5 (/var/log/almalinux-deploy.debug.log) leaked on vgs invocation. Parent PID 104330: /usr/sbin/grub2-probe
File descriptor 5 (/var/log/almalinux-deploy.debug.log) leaked on vgs invocation. Parent PID 104902: /usr/sbin/grub2-probe
File descriptor 5 (/var/log/almalinux-deploy.debug.log) leaked on vgs invocation. Parent PID 104902: /usr/sbin/grub2-probe
done
All Secure Boot related packages which were released by not AlmaLinux are reinstalledOK
Migration to AlmaLinux is completed

Then run following command to synchronize installed packages

sudo dnf distro-sync -y 

Next,reboot your system to boot into the fresh instance of AlmaLinux

sudo reboot

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while booting the grub menu will appear with the AlmaLinux as shown below

once your system is booted, you can verify the AlmaLinux operating system version using the following command.

cat /etc/os-release

output:

NAME="AlmaLinux"
VERSION="8.4 (Electric Cheetah)"
ID="almalinux"
ID_LIKE="rhel centos fedora"
VERSION_ID="8.4"
PLATFORM_ID="platform:el8"
PRETTY_NAME="AlmaLinux 8.4 (Electric Cheetah)"
ANSI_COLOR="0;34"
CPE_NAME="cpe:/o:almalinux:almalinux:8.4:GA"
HOME_URL="https://almalinux.org/"
DOCUMENTATION_URL="https://wiki.almalinux.org/"
BUG_REPORT_URL="https://bugs.almalinux.org/"
ALMALINUX_MANTISBT_PROJECT="AlmaLinux-8"
ALMALINUX_MANTISBT_PROJECT_VERSION="8.4"

That's it. Now you have successfully migrated from centos 8 to Alma Linux.

Also Read -> How to Migrate from Centos 8 to Alma Linux 8