Chapter 8. Converting a host to Red Hat Enterprise Linux
You can convert Red Hat Enterprise Linux derivative distributions into a supportable Red Hat Enterprise Linux on a host while retaining installed applications and configurations. Satellite provides Convert2RHEL utilities to simplify the conversion process.
The Convert2RHEL utilities in Satellite contain an Ansible role and Ansible Playbook. You use the Ansible role to generate conversion data on Satellite Server, which includes enabling required repositories and creating products, activation keys, and host groups. Then you perform the actual conversion on the host by using the Ansible Playbook, which installs the Convert2RHEL CLI tool on the host and runs it.
You can use the Ansible role to generate conversion data for the following conversions:
- CentOS Linux 7 to Red Hat Enterprise Linux 7
- Oracle Linux 7 to Red Hat Enterprise Linux 7
- Oracle Linux 8 to Red Hat Enterprise Linux 8
These conversions are supported by Red Hat.
The conversion process is similar to a minor release upgrade of Red Hat Enterprise Linux in which every RPM package on the system is replaced. Third-party packages and non-Red Hat packages that are not available in Red Hat Enterprise Linux are retained.
The Convert2RHEL utility removes unnecessary packages such as logos or packages known to cause issues during the conversion. The utility replaces the CentOS-release
or Oracle-release
package with the rhel-release
package, and all packages signed by CentOS or Oracle with their Red Hat equivalents. The utility also subscribes the host to Red Hat Subscription Management.
The duration of the conversion process depends on the number of packages that have to be replaced, network speed, storage speed, and similar factors.
Prerequisites
- Review Supported conversion paths in Red Hat Enterprise Linux 8 Converting from a Linux distribution to RHEL using the Convert2RHEL utility.
- You must have completed the steps 1. – 5. of the procedure Preparing for a RHEL conversion in Red Hat Enterprise Linux 8 Converting from a Linux distribution to RHEL using the Convert2RHEL utility.
Ensure you have a subscription manifest uploaded to your Satellite and that there are sufficient Red Hat Enterprise Linux entitlements allocated for the conversions you intend. Alternatively, you can use Ansible variables to tell the role to import the manifest from disk. The manifest must be imported to the organization to which you will register hosts for conversion.
You can update your allocations and download the updated manifest from the Red Hat Customer Portal. For more information, see Exporting and downloading a manifest in Creating and managing manifests for a connected Satellite Server.
- Ensure that you have enabled and synchronized Red Hat repositories in Satellite for the minor Red Hat Enterprise Linux version to which you convert your hosts. For more information, see Enabling Red Hat Repositories and Synchronizing Repositories in Managing content.
High-level conversion steps
-
Import the
redhat.satellite.convert2rhel
Ansible role and variables. For more information, see Importing Ansible Roles and Variables in Managing configurations by using Ansible integration. - Configure Ansible variables for generation of conversion data. For more information, see Section 8.1, “Ansible variables for conversion”.
-
Assign the
redhat.satellite.convert2rhel
role to the host that represents Satellite Server. For more information, see Assigning Ansible Roles to an Existing Host in Managing configurations by using Ansible integration. Run the Ansible role on Satellite Server. For more information, see Running Ansible Roles on a Host in Managing configurations by using Ansible integration.
The Ansible role generates data required for host conversion, that is, repositories, certificates, activation keys, and host groups. The role enables the
rhel-7-server-rpms
repository with the 7Server release and x86_64 architecture, orrhel-8-for-x86_64-baseos-rpms
andrhel-8-for-x86_64-appstream-rpms
, or both, depending on which variables you have set in the previous steps.Register a host for conversion by using a generated host group.
Use the global registration template to register and subscribe your host before the conversion. Select the host group that was generated for the conversion you intend, such as
CentOS 7 converting
if you convert the host from CentOS 7. For more information, see Section 4.3, “Registering hosts by using global registration”.Run the pre-conversion analysis on the host group to verify if your hosts are ready for the conversion. Execute a remote job with the following settings:
-
Job category:
Convert 2 RHEL
Job template:
Convert2RHEL analyze
For more information, see Section 13.22, “Executing a remote job”.
Review pre-conversion analysis reports and resolve all issues that are blocking the conversion. Repeat this step until you resolve all blocking issues. For more information, see Reviewing the pre-conversion analysis report in Red Hat Enterprise Linux 8 Converting from a Linux distribution to RHEL using the Convert2RHEL utility.
-
Job category:
Run the Convert2RHEL playbook on the host group. Execute a remote job with the following settings:
-
Job category:
Convert 2 RHEL
-
Job template:
Convert to RHEL
Activation key:
-
convert2rhel_rhel7
if you convert to Red Hat Enterprise Linux 7 -
convert2rhel_rhel8
if you convert to Red Hat Enterprise Linux 8
-
For more information, see Section 13.22, “Executing a remote job”.
-
Job category:
Additional resources
- How to perform an unsupported conversion from a RHEL-derived Linux distribution to RHEL in the Red Hat Knowledgebase
8.1. Ansible variables for conversion
Before you run the Ansible role to generate conversion data, configure values of the following required Ansible variables.
Satellite imports most of the required Ansible variables from the redhat.satellite.convert2rhel
role. However, some variables are not imported. These variables are marked with an asterisk *
in the tables below. You must create those additional variables manually and assign them to the redhat.satellite.convert2rhel
role.
Name | Type | Intent and value |
---|---|---|
| string |
URL of your Satellite Server, such as |
| string | Your user name |
| string | Your password |
| string | Name of your organization |
| boolean |
Set to |
| boolean |
Set to |
| boolean |
Set to |
| boolean |
Enables Red Hat Enterprise Linux 7 repositories. Set to |
| boolean |
Set to |
| boolean |
Enables Red Hat Enterprise Linux 8 repositories. Set to |
| boolean |
Set to |
Name | Type | Intent and value |
---|---|---|
| string |
Path to a manifest to upload from disk, such as |
| string |
Minor release version, such as |