Systems Management with SUSE Linux Enterprise Server 16

Sebastian wrote recently about SUSE Linux Enterprise Server 16  and talked about leveraging Linux innovation with a better Linux. Today, let’s dive a bit deeper into how SUSE wants to improve systems management with SUSE Linux Enterprise 16.

Changes in the Management Tools

For systems management, we revised the plan taking into account two aspects:

First, to help IT administrators to set up and manage systems, many use automation for repetitive tasks, some even for single tasks. Using automation allows admins to test and review complex procedures and then run them whenever needed. Second, for some manual tasks, administration and basic monitoring is often done from various devices – including mobile ones – and thus a web frontend is key for remote management.

Also, it’s imperative for us to allow admins to mix methods and give them choice. Thus, let’s look at manual steps for installation and system administration and then discuss automation of these.

Agama: Manual installation

Many admins will use ready-to-run images, especially in public cloud and virtual environments. SUSE will continue to provide those with version 16 – as we do today.

For some scenarios and often for bare-metal installations, a traditional installer gives full customization of an installation.

For installation, we used the proven YaST technology and created a new Linux installer – it’s called Agama. The YaST team developed it, leveraging decades of Linux installer experience.

Agama can perform interactive and unattended installations. It comes with two user interfaces: A modern web front-end and a powerful command-line tool. In addition, a HTTP API allows control and monitoring of installations.

Agama focuses on system installation – unlike YaST that is known both as Linux installer and general configuration tool. Thus, Agama, covers especially

• Configure network and storage setup potentially including remote storage, partitioning, LVM, encryption, etc. 
• Deploy the target system over that storage setup eg. installing the appropriate set of RPM packages.
• Customise the aspects of the system needed for the first boot, like boot loader, kdump, authentication, etc. 

Once the OS installation is done, the job of Agama is done – the administrator will set up the workload and manage the system.

Cockpit: Web-Based Server Management

Cockpit allows remote management of a system through its web interface and modules. An administrator can see their server in a web browser and perform system tasks like starting containers, configuring networks, administrating storage, inspecting logs and processes.

Agama: Unattended Installation

Admins often want to install systems automatically with a so-called unattended installation.

Customers have been using AutoYaST profiles to create complex installation scripts and then run them for installation. The team working on the new installer Agama has been looking at two aspects: How can administrators leverage their existing AutoYaST profiles? How can they ease the writing of such automation scripts?

Upgrading from AutoYaST

Agama is in general backward-compatible with AutoYaST, no conversion is needed. With the reduced scope of Agama – only installation – some functionality, like configuring a DHCP or DNS server with AutoYaST, is not part of Agama anymore. Agama will read an AutoYaST profile and ignore these out of scope settings and apply those that it handles, like partitioning.

Agama-Native Automation

Agama has its own language based on JSON with some programming (JSONNET) that is easier to write than AutoYaST. The goal here is to provide really just the needed information, for example a list of wanted mount points and minimal sizes, instead of the fully-defined partitioning in AutoYaST.

Agama also allows exporting settings to a file so that these can be reused for an automatic installation. The export is minimal as it includes only changes to the defaults without any noise.

Automation with Ansible

To set up systems initially – once the OS is up and – administrators often prefer an automation engine like Salt or Ansible. With SLES 16, we decided to put our focus on automation with Ansible as this technology is more widely used nowadays. 

Salt itself will only be supported as part of our SUSE Multi-Linux Manager product, as it manages systems using Salt and Ansible.

Besides the Ansible automation engine, SUSE will deliver ready to run automation scripts – roles and playbooks – for day 1 and day 2 automation. These include the linux system roles and the SAP roles. The SAP roles for example allow the setup of a complete SAP HANA cluster, even with high availability.

YaST in maintenance mode

With the development of SLES 16, SUSE is putting YaST into maintenance mode. The installation and configuration tool YaST will continue to be fully supported as part of SLES 15. For SLES 16, some of YaST’s components are used as base of Agama, YaST as a tool is replaced by Agama, Cockpit and Ansible.

SLES 16: A Future-Ready Linux

With SLES 16, SUSE is modernizing the software management stack with new tools that enable full system automation or manual setup from the browser. These tools are designed to work seamlessly together, enabling administrators to mix paradigms if they choose and do for example:

• Start Agama manually, import the profile to get your default settings
• Adapt to your individual configuration if needed
• Tell Agama to install the OS
• Let Ansible run once Agama is finished
• Finally use cockpit to inspect the system and do further changes
• Use Ansible for routine tasks like patching a system

That’s just one way of doing it. 

Others might do the full automatic configuration with:

• Start Agama and do an automatic installation
• Let Ansible run once Agama is finished
• Enjoy the fully set up system

To learn more about SUSE Linux Enterprise Server 16.0, check this introductory article and the article “Why Change? Innovations in SUSE Linux Enterprise Server 16”.