Registering CentOS Clients

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

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 Manager Server to the CentOS content delivery network.

Traditional clients are not available on CentOS 8. CentOS 8 clients are only supported as Salt clients.

Registering CentOS clients to SUSE 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 Manager.

1. Add Software Channels

Before you can register CentOS clients to your SUSE 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 client-configuration:supported-features.adoc.

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

Table 1. CentOS Products - WebUI
OS Version Product Name

CentOS 6

CentOS 6 x86_64

CentOS 7

CentOS 7 x86_64

CentOS 8

CentOS 8 x86_64

CentOS 6 is now at end-of-life, and the ISO images provided in the repository are out of date. Bootstrapping new CentOS 6 clients using these packages will fail. If you need to bootstrap new CentOS 6 clients, follow the troubleshooting procedure in client-configuration:tshoot-clients.adoc.

Procedure: Adding Software Channels
  1. In the SUSE Manager Web UI, navigate to Admin  Setup Wizard  Products.

  2. 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 required channels. Click the arrow to see the complete list of related products, and ensure that any extra products you require are checked.

  3. 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 6

centos6-x86_64

CentOS 7

centos7-x86_64

CentOS 8

centos8-x86_64

CentOS 6 is now at end-of-life, and the ISO images provided in the repository are out of date. Bootstrapping new CentOS 6 clients using these packages will fail. If you need to bootstrap new CentOS 6 clients, follow the troubleshooting procedure in client-configuration:tshoot-clients.adoc.

Procedure: Adding Software Channels at the Command Prompt
  1. At the command prompt on the SUSE Manager Server, as root, use the mgr-sync command to add the appropriate channels:

    mgr-sync add channel <channel_label_1>
    mgr-sync add channel <channel_label_2>
    mgr-sync add channel <channel_label_n>
  2. Synchronization starts automatically. If you want to synchronize the channels manually, use:

    mgr-sync sync --with-children <channel_name>
  3. 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 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 Manager keeps all of them, regardless of age.

The AppStream repository provides modular packages. This results in the SUSE Manager Web UI showing incorrect package information. You cannot perform package operations such as installing or upgrading directly from modular repositories using the Web UI or API.

You can use the AppStream filter with content lifecycle management (CLM) to transform modular repositories into regular repositories. Make sure to include python:3.6 using an AppStream filter if you want to use spacecmd on the clients.

Alternatively, you can use Salt states to manage modular packages on Salt clients, or use the dnf command on the client. For more information about CLM, see administration:content-lifecycle.adoc.

2. Check Synchronization Status

Procedure: Checking Synchronization Progress
  1. In the SUSE 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.

  2. 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
  1. At the command prompt on the SUSE Manager Server, as root, use the tail command to check the synchronization log file:

    tail -f /var/log/rhn/reposync/<channel-label>.log
  2. 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 client-configuration:activation-keys.adoc.

4. Register Clients

CentOS clients are registered in the same way as all other clients. For more information, see client-configuration:registration-overview.adoc.

To register and use CentOS 6 clients, you need to configure the SUSE Manager Server to support older types of SSL encryption. For more information about how to resolve this error, see Registering Older Clients at client-configuration:tshoot-clients.adoc.

5. Manage Errata

When you update CentOS clients, the packages do not include metadata about the updates. You can use a third-party errata service to obtain this information.

The third-party errata service described here, CEFS, is provided and maintained by the community. It is not supported by SUSE.

The authors of CEFS provide patches or errata on a best-effort basis, in the hope they are useful but with no guarantees of correctness or currency. This could mean that the patch dates could be incorrect, and in at least one case, the published data was shown to be more than a month old. For more information on these cases, see https://github.com/stevemeier/cefs/issues/28#issuecomment-656579382 and https://github.com/stevemeier/cefs/issues/28#issuecomment-656573607.

Any problems or delays with the patch data might result in unreliable patch information being imported to your SUSE Manager Server. This would cause reports, audits, CVE updates, or other patch-related information to also be incorrect. Please consider alternatives to using this service, such as independently verifying patch data, or choosing a different operating system, depending on your security-related requirements and certifications criteria.

Procedure: Installing an Errata Service
  1. On the SUSE Manager Server, from the command prompt, as root, add the sle-module-development-tools module:

    SUSEConnect --product sle-module-development-tools/15.2/x86_64
  2. Install errata service dependencies:

    zypper in  perl-Text-Unidecode
  3. Add or edit this line in /etc/rhn/rhn.conf:

    java.allow_adding_patches_via_api = centos7-updates-x86_64,centos7-x86_64,centos7-extras-x86_64
  4. Restart Tomcat:

systemctl restart tomcat
  1. Create a file for your errata script:

    touch /usr/local/bin/cent-errata.sh
  2. Edit the new file to include this script, editing the repository details as required. This script fetches the errata details from an external errata service, unpacks it, and publishes the details:

    #!/bin/bash
    mkdir -p /usr/local/centos
    cd /usr/local/centos
    rm *.xml
    wget -c http://cefs.steve-meier.de/errata.latest.xml
    #wget -c https://www.redhat.com/security/data/oval/com.redhat.rhsa-all.xml
    wget -c https://www.redhat.com/security/data/oval/com.redhat.rhsa-RHEL7.xml
    wget -c http://cefs.steve-meier.de/errata-import.tar
    tar xvf errata-import.tar
    chmod +x /usr/local/centos/errata-import.pl
    export SPACEWALK_USER='<adminname>';export SPACEWALK_PASS='<password>'
    /usr/local/centos/errata-import.pl --server '<servername>' \
    --errata /usr/local/centos/errata.latest.xml  \
    --include-channels=centos7-updates-x86_64,centos7-x86_64,centos7-extras-x86_64 \
    --publish --rhsa-oval /usr/local/centos/com.redhat.rhsa-RHEL7.xml
  3. Set up a cron job to run the script daily:

    ln -s /usr/local/bin/cent-errata.sh /etc/cron.daily

For more information on this tool, see https://cefs.steve-meier.de/.