Jump to contentJump to page navigation: previous page [access key p]/next page [access key n]
documentation.suse.com / Layered Stack Deployment of Rancher Kubernetes Engine / Component model
Applies to SUSE Linux Enterprise Server 15 SP3, Rancher Kubernetes Engine 1.2.16

4 Component model

This section describes the various components being used to create a Rancher Kubernetes Engine solution deployment, in the perspective of top to bottom ordering. When completed, the Rancher Kubernetes Engine instance can be used as the application infrastructure for cloud-native workloads and can be imported into SUSE Rancher for management.

4.1 Component overview

By using:

  • Kubernetes Platform - Rancher Kubernetes Engine

  • Operating System - SUSE Linux Enterprise Server

  • Compute Platform

    • Ampere Altra Family

you can create the necessary infrastructure and services. Further details for these components are described in the following sections.

4.2 Software - Rancher Kubernetes Engine

Rancher Kubernetes Engine is a CNCF-certified Kubernetes distribution that runs entirely within Docker containers. It solves the common frustration of installation complexity with Kubernetes by removing most host dependencies and presenting a stable path for deployment, upgrades, and rollbacks.

With Rancher Kubernetes Engine [RKE], the operation of Kubernetes is easily automated and entirely independent of the operating system and platform you are running. As long as you can run a supported version of Docker, you can deploy and run Kubernetes with RKE. It builds a cluster from a single command in a few minutes, and its declarative configuration makes Kubernetes upgrades atomic and safe.

What is provided with Rancher Kubernetes Engine
  • CNCF Certification

    • Rancher Kubernetes Engine CNCF certification means that every release supports the same APIs as upstream Kubernetes. This gives enterprises the confidence that their Kubernetes resources are portable between RKE and other CNCF-certified Kubernetes distributions.

  • Simplified installation

    • Installation is via a single binary and it uses a single YAML file, meaning that even non-experts can deploy Kubernetes with a single command. The command connects to remote hosts via SSH, so Rancher or any staff member with SSH access can deploy and manage RKE instances anywhere in the world.

  • Automated Operation

    • When used with SUSE Rancher, operators can perform automated installation and upgrades of RKE clusters with a few clicks.

  • Vendor Independence

    • RKE is not locked into a specific vendor operating system, Kubernetes Management Platform or proprietary tooling.

  • Safe, Atomic Upgrades

    • Since RKE is built using containers, it does not have any touch points with the underlying operating system beyond the container engine. Containers make it easy to upgrade to a new version and to roll back to the previous version if necessary.

  • 24x7 Enterprise-level Support

    • Ensures around-the-clock support from technical experts when you need it.

The fundamental roles for the nodes and core functionality of Rancher Kubernetes Engine are represented in the following figure:

RKE1 overview
Figure 4.1: Component Overview - Rancher Kubernetes Engine
  • Kubernetes API Server,

    • interacts with kubelet on all the nodes, plus addresses authentication, user interface (UI), command line interface (CLI) and API for external access and cluster management via SUSE Rancher cluster controller to agent

While all Rancher Kubernetes Engine roles can be installed on a single system, for the best availability, performance and security, the recommended deployment of a Rancher Kubernetes Engine cluster is a pair of nodes for the control plane role, at least three etcd role-based nodes and three or more worker nodes.

Rancher Kubernetes Engine can run as a complete cluster on a single node or can be expanded into a multi-node cluster. Besides the core Kubernetes components, these are also configurable and included:

  • Multiple Kubernetes versions

  • CoreDNS, Metrics, Ingress controller

  • CNI : Canal, Calico, Flannel, Weave

  • Support for a Windows worker agent node (only with Flannel)

  • Fleet Agent : for GitOps deployment of cloud-native applications

All of these components are configurable and can be swapped out for your implementation of choice. With these included components, you get a fully functional and CNCF-conformant cluster so you can start running apps right away.

Tip
Tip

Learn more information about Rancher Kubernetes Engine at https://rancher.com/docs/rke/latest/en/.

While all Rancher Kubernetes Engine roles can be installed on a single system, a multi-node cluster, is a more production-like approach and will be described in the deployment section.

Tip
Tip

To improve availability, performance and security, the recommended deployment of a Rancher Kubernetes Engine cluster is a pair of nodes for the control plane role, at least three etcd role-based nodes and three or more worker nodes.

4.3 Software - SUSE Linux Enterprise Server

SUSE Linux Enterprise Server (SLES) is an adaptable and easy-to-manage platform that allows developers and administrators to deploy business-critical workloads on-premises, in the cloud and at the edge. It is a Linux operating system that is adaptable to any environment – optimized for performance, security and reliability. As a multimodal operating system that paves the way for IT transformation in the software-defined era, this simplifies multimodal IT, makes traditional IT infrastructure efficient and provides an engaging platform for developers. As a result, one can easily deploy and transition business-critical workloads across on-premises and public cloud environments.

Designed for interoperability, SUSE Linux Enterprise Server integrates into classical Unix and Windows environments, supports open standard interfaces for systems management, and has been certified for IPv6 compatibility. This modular, general purpose operating system runs on four processor architectures and is available with optional extensions that provide advanced capabilities for tasks such as real time computing and high availability clustering. SUSE Linux Enterprise Server is optimized to run as a high performing guest on leading hypervisors and supports an unlimited number of virtual machines per physical system with a single subscription. This makes it the perfect guest operating system for virtual computing.

4.4 Compute Platform

Leveraging the enterprise grade functionality of the operating system mentioned in the previous section, many compute platforms can be the foundation of the deployment:

  • Virtual machines on supported hypervisors or hosted on cloud service providers

  • Physical, baremetal or single-board computers, either on-premises or hosted by cloud service providers

Note
Note

To complete self-testing of hardware with SUSE YES Certified Process, you can download and install the respective SUSE operating system support-pack version of SUSE Linux Enterprise Server and the YES test suite. Then run the tests per the instructions in the test kit, fixing any problems encountered and when corrected, re-run all tests to obtain clean test results. Submit the test results into the SUSE Bulletin System (SBS) for audit, review and validation.

Tip
Tip

Certified systems and hypervisors can be verified via SUSE YES Certified Bulletins and then can be leveraged as supported nodes for this deployment, as long as the certification refers to the respective version of the underlying SUSE operating system required.

4.4.1 Ampere Altra Family

The Ampere Altra Arm v8.2 processor portfolio of world’s first cloud native processors is widely available with data center ready configurations from our systems partners and for use with many Cloud Service Providers. Explore the Ampere Computing Platforms offered from our partners. These systems are flexible enough to meet the needs of any cloud deployment and come packed with Ampere 80-core Altra or 128-core Altra Max processors.

The specific processor models that offer relevant choices for Enterprise Kubernetes are designed to meet the requirements of modern data centers, deliver predictable performance, high scalability, and power efficiency for data center deployments from hyperscale cloud to the edge cloud. These processorst that drive efficiency in your data center infrastructure workloads, including data analytics, artificial intelligence, database storage, telco stacks, edge computing, and Web hosting, are:

  • Ampere Altra 64-Bit Multi-Core Processor

    • Predictable Performance - Ampere Altra offers up to 80 cores at up to 3.30 GHz speed maximum. Each core is single-threaded by design with its own 64 KB L1 I-cache, 64 KB L1 D-cache, and a huge 1 MB L2 cache, delivering predictable performance all along by eliminating the noisy neighbor challenge within each core.

    • Power Efficiency - provides industry-leading power efficiency/core, while packing 80 cores in a single-socket and 160 cores in a dual-socket platform, establishing new levels of power efficiency with scalability to meet the most strenuous application infrastructure needs.

  • Ampere Altra Max 64-Bit Multi-Core Processor

    • Predictable Performance - Ampere Altra Max offers up to 128 cores operating at a maximum of 3.0 GHz. Each core is single-threaded by design with its own 64 KB L1 I-cache, 64 KB L1 D-cache, and a huge 1 MB L2 cache, delivering predictable performance 100% of the time by eliminating the noisy neighbor challenge within each core.

    • Power Efficiency - provides industry-leading power efficiency/core, while packing 128 cores in a single-socket and 256 cores in a dual-socket platform, establishing new levels of power efficiency with scalability.

Furthermore, each of these processors features:

  • High Scalability - With leading power/core, and multi-socket support, it provides the scalability to maximize the number of servers per rack, unparalleled in the industry.

  • Reliability, Availability, and Serviceability (RAS) - provides extensive enterprise-class RAS capabilities. Data in memory is protected with advanced ECC in addition to standard DDR4 RAS features. End-to-end data poisoning ensures corrupted data is tagged and any attempt to use it is flagged as an error. The SLC is also ECC protected, and the processor supports background scrubbing of the SLC cache and DRAM to locate and correct single-bit errors before they accumulate into uncorrectable errors.

Note
Note

A sample bill of materials, in the Chapter 9, Appendix, cites the necessary quantites of all components, along with a reference to the minimum resource requirements needed by the software components.