Registering CentOS Clients

This section contains information about registering clients running CentOS operating systems.

CentOS repository URLs are available from SUSE Customer Center.
Packages and metadata are provided by CentOS, not by SUSE.
For supported products, see the release notes and the support table at Supported CentOS Features.

CentOS clients are based on CentOS and are unrelated to SUSE Linux Enterprise Server with Expanded Support, RES, Red Hat, or Expanded Support.

You are responsible for arranging access to CentOS base media repositories and CentOS installation media, as well as connecting SUSE Multi-Linux Manager Server to the CentOS content delivery network.

Registering CentOS clients to SUSE Multi-Linux Manager is tested with the default SELinux configuration of enforcing with a targeted policy. You do not need to disable SELinux to register CentOS clients to SUSE Multi-Linux Manager.

1. Add Software Channels

Before you can register CentOS clients to your SUSE Multi-Linux Manager Server, you need to add the required software channels, and synchronize them.

The architectures currently supported are: x86_64 and aarch64. For full list of supported products and architectures, see Supported Clients and Features.

In the following section, descriptions often default to the x86_64 architecture. Replace it with other architectures if appropriate.

For example, when working with x86_64 architecture, you need this products:

Table 1. CentOS Products - WebUI
OS Version	Product Name
CentOS 7	CentOS 7 x86_64

Procedure: Adding Software Channels

In the SUSE Multi-Linux Manager Web UI, navigate to Admin Setup Wizard Products.
Locate the appropriate products for your client operating system and architecture using the search bar, and check the appropriate product. This will automatically check all mandatory channels. Also all recommended channels are checked as long as the include recommended toggle is turned on. Click the arrow to see the complete list of related products, and ensure that any extra products you require are checked.
Click Add Products and wait until the products have finished synchronizing.

Alternatively, you can add channels at the command prompt. The channels you need for this procedure are:

Table 2. CentOS Channels - CLI
OS Version	Base Channel
CentOS 7	centos7-x86_64

Procedure: Adding Software Channels at the Command Prompt

At the command prompt on the SUSE Multi-Linux Manager container host, as root, add the appropriate channels:

mgrctl exec -ti -- mgr-sync add channel <channel_label_1>
mgrctl exec -ti -- mgr-sync add channel <channel_label_2>
mgrctl exec -ti -- mgr-sync add channel <channel_label_n>

Synchronization starts automatically. If you want to synchronize the channels manually, use:
```
mgrctl exec -ti -- mgr-sync sync --with-children <channel_name>
```
Ensure the synchronization is complete before continuing.

If you are using modular channels, you must enable the Python 3.6 module stream on the client. If you do not provide Python 3.6, the installation of the spacecmd package will fail.

You might notice some disparity in the number of packages available in the AppStream channel between upstream and the SUSE Multi-Linux Manager channel. You might also see different numbers if you compare the same channel added at a different point in time. This is due to the way that CentOS manages their repositories. CentOS removes older version of packages when a new version is released, while SUSE Multi-Linux Manager keeps all of them, regardless of age.

2. Check Synchronization Status

Procedure: Checking Synchronization Progress From the Web UI

In the SUSE Multi-Linux Manager Web UI, navigate to Admin Setup Wizard and select the Products tab. This dialog displays a completion bar for each product when they are being synchronized.
Alternatively, you can navigate to Software Manage Channels, then click the channel associated to the repository. Navigate to the Repositories tab, then click Sync and check Sync Status.

Procedure: Checking Synchronization Progress From the Command Prompt

At the command prompt on the SUSE Multi-Linux Manager container host, as root, check the synchronization log file:
```
mgrctl exec -ti -- tail -f /var/log/rhn/reposync/<channel-label>.log
```
Each child channel generates its own log during the synchronization progress. You need to check all the base and child channel log files to be sure that the synchronization is complete.

3. Create an Activation Key

You need to create an activation key that is associated with your CentOS channels.

For more information on activation keys, see Activation Keys.

4. Manage GPG Keys

Clients use GPG keys to check the authenticity of software packages before they are installed. Only trusted software can be installed on clients.

Trusting a GPG key is important for security on clients. It is the task of the administrator to decide which keys are needed and can be trusted. Because a software channel cannot be used when the GPG key is not trusted, the decision of assigning a channel to a client depends on the decision of trusting the key.

For more information about GPG keys, see GPG Keys.

5. Register Clients

To register your clients, you need a bootstrap repository. By default, bootstrap repositories are automatically created, and regenerated daily for all synchronized products. You can manually create the bootstrap repository from the command prompt on the container host:

mgrctl exec -ti mgr-create-bootstrap-repo

For more information on registering your clients, see Client Registration.