ELevate Quickstart Guide

Before beginning, we HIGHLY recommend that you follow system administration best practices and make sure you have backups and/or snapshots of your system before you proceed. It is recommended to do a trial run in a sandbox to verify that migration worked as expected before you attempt to migrate any production system. Please report any issues encountered to the AlmaLinux Bug Tracker and/or AlmaLinux Chat Migration Channel

The ELevate project only supports official operating systems repositories. It doesn’t support external repositories like EPEL. Please, check the ELevate Frequent Issues page for known and frequent issues.

This guide contains steps on how to upgrade your RHEL-based operating system to the next major version.

Currently, the following migration directions are available:

* - migration to CentOS Stream 9 is currently in process and will be available later.

** - migration to Oracle Linux 9 is available with the Oracle Leapp utility and will not be supported by ELevate project.

You need CentOS 7, AlmaLinux 8, EuroLinux 8 or Rocky Linux 8 system installed to use this guide.

• Fully updated system is required to accomplish the upgrade. So, install the latest updates first, and reboot.

sudo yum update -y
sudo reboot

• Install elevate-release package with the project repo and GPG key.

sudo yum install -y http://repo.almalinux.org/elevate/elevate-release-latest-el$(rpm --eval %rhel).noarch.rpm

• Install leapp packages and migration data for the OS you want to upgrade. Possible options are:
  • leapp-data-almalinux
  • leapp-data-centos
  • leapp-data-eurolinux
  • leapp-data-oraclelinux
  • leapp-data-rocky

sudo yum install -y leapp-upgrade leapp-data-almalinux

• Start a preupgrade check. In the meanwhile, the Leapp utility creates a special /var/log/leapp/leapp-report.txt file that contains possible problems and recommended solutions. No rpm packages will be installed at this phase.

Preupgrade check will fail as the default install doesn't meet all requirements for migration.

sudo leapp preupgrade

This summary report will help you get a picture of whether it is possible to continue the upgrade.

:::tip
In certain configurations, Leapp generates /var/log/leapp/answerfile with true/false questions. Leapp utility requires answers to all these questions in order to proceed with the upgrade.
:::

• The following fixes from the /var/log/leapp/leapp-report.txt file are the most popular for CentOS 7, but it's recommended to review the whole file.

sudo rmmod pata_acpi
echo PermitRootLogin yes | sudo tee -a /etc/ssh/sshd_config
sudo leapp answer --section remove_pam_pkcs11_module_check.confirm=True

• Here are the most popular fixes for RHEL8-based operating systems:

sudo sed -i "s/^AllowZoneDrifting=.*/AllowZoneDrifting=no/" /etc/firewalld/firewalld.conf
sudo leapp answer --section check_vdo.no_vdo_devices=True

Check the ELevate Frequent Issues page for known and frequent issues and guidance steps to solve them.

• Start an upgrade. You'll be offered to reboot the system after this process is completed.

sudo leapp upgrade
sudo reboot

• A new entry in GRUB called ELevate-Upgrade-Initramfs will appear. The system will be automatically booted into it.
  See how the update process goes in the console.

• After reboot, login to the system and check how the migration went. Verify that the current OS is the one you need. Check logs and packages left from previous OS version, consider removing them or update manually.

cat /etc/redhat-release
cat /etc/os-release
rpm -qa | grep el7 # for 7 to 8 migration
rpm -qa | grep el8 # for 8 to 9 migration
cat /var/log/leapp/leapp-report.txt
cat /var/log/leapp/leapp-upgrade.log

ELevating CentOS 7 to AlmaLinux 9

As the Leapp tool is designed to perform one-step migrations, to migrate your CentOS 7.x machine to AlmaLinux 9.x you need to split the migration process from CentOS 7.x to AlmaLinux 8.x and AlmaLinux 8.x to AlmaLinux 9.x.

When successfully migrated to AlmaLinux 8.x OS, consider performing these steps to prepare your system for migration to AlmaLinux 9.x:

1. Navigate to the /etc/ directory and use an editor of your choice to edit the yum.conf file. You need to remove everything from the exclude line especially that refers to elevate or leapp.

   An example of yum.conf file:

   ​​​[main]
   ​​​gpgcheck=1
   ​​​installonly_limit=3
   ​​​clean_requirements_on_remove=True
   ​​​best=True
   ​​​skip_if_unavailable=False
   ​​​exclude=python2-leapp,snactor,leapp-upgrade-el7toel8,leapp
   

2. Then navigate to the /etc/dnf/ directory and use an editor of your choice to do the same in the dnf.conf file.

3. Now you can remove/manually upgrade packages left from CentOS 7.x without any conflicts.

4. Check packages left from CentOS 7:

   ​​​rpm -qa | grep el7
   

   An example output with a list of packages:

   ​​​leapp-upgrade-el7toel8-0.16.0-6.el7.elevate.17.noarch
   ​​​yum-plugin-fastestmirror-1.1.31-54.el7_8.noarch
   ​​​python2-leapp-0.14.0-1.el7.noarch
   ​​​leapp-data-almalinux-0.1-6.el7.noarch
   ​​​kernel-3.10.0-1160.102.1.el7.x86_64
   ​​​kernel-3.10.0-1160.el7.x86_64
   ​​​java-1.7.0-openjdk-headless-1.7.0.261-2.6.22.2.el7_8.x86_64
   ​​​btrfs-progs-4.9.1-1.el7.x86_64
   ​​​elevate-release-1.0-2.el7.noarch
   ​​​leapp-0.14.0-1.el7.noarch
   

   As mentioned above, consider removing these packages or upgrading them manually to proceed with migration to AlmaLinux 9.x.

   If you face difficulties while removing the packages, the following command might help you:

   ​​​rpm -e --nodeps <package_name>
   

5. You can also check for the packages left from the migration process and remove them:

   ​​​rpm -qa | grep elevate
   ​​​rpm -qa | grep leapp
   

6. Check whether you have the /root/tmp_leapp_py3 directory created and if so delete it.

7. Clean up your machine.

   ​​​sudo dnf clean all
   

8. You may also have to remove old RSA/SHA1 GPG keys. List the keys:

   ​​​rpm -q gpg-pubkey --qf '%{NAME}-%{VERSION}-%{RELEASE}\t%{SUMMARY}\n'
   

   To remove them, use use the rpm -e command:

   ​​​rpm -e [keyname]
   

9. After these preparations are completed, you can follow steps from the ELevate Quickstart Guide to migrate your AlmaLinux.x machine to AlmaLinux 9.x.

A few more useful tips

• After the leapp preupgrade step fails, check the logs and apply the fixes. The most popular fixes for RHEL8-based operating systems:

  ​​​sudo sed -i "s/^AllowZoneDrifting=.*/AllowZoneDrifting=no/" /etc/firewalld/firewalld.conf
  ​​​sudo leapp answer --section check_vdo.no_vdo_devices=True
  

  You might also find the following issue in the leapp-report file that can interfere with the migration. Consider removing the file:

  ​​​ Network configuration for unsupported device types detected
  ​​​ Summary: RHEL 9 does not support the legacy network-scripts package that was deprecated in RHEL 8 in favor of NetworkManager. Files for device types that are not supported by NetworkManager are present in the system. Files with the problematic configuration:
  ​​​   - /etc/sysconfig/network-scripts/ifcfg-eth0
  

• You might want to remove the make-devel package as it conflicts when running leapp upgrade and thus this step fails.

• After successful migration to AlmaLinux 9.x don't forget to verify you got the system you needed and if there are left-over packages you might want to remove:

  ​​​rpm -qa | grep el8
  ​​​rpm -qa | grep elevate
  ​​​rpm -qa | grep leapp
  

Demo Video

Check Demo of a CentOS 7.x to AlmaLinux 8.x migration using the software and data provided by the AlmaLinux ELevate Project.