Chapter 1. Getting ready to install MicroShift
Plan for your Red Hat Device Edge by planning your Red Hat Enterprise Linux (RHEL) installation type and your MicroShift configuration.
1.1. System requirements for installing MicroShift
The following conditions must be met prior to installing MicroShift:
- A compatible version of Red Hat Enterprise Linux (RHEL). For more information, see Compatibility table.
- AArch64 or x86_64 system architecture.
- 2 CPU cores.
- 2 GB RAM. Installing from the network (UEFI HTTPs or PXE boot) requires 3 GB RAM for RHEL.
- 10 GB of storage.
- You have an active MicroShift subscription on your Red Hat account. If you do not have a subscription, contact your sales representative for more information.
- if your workload requires Persistent Volumes (PVs), you have a Logical Volume Manager (LVM) Volume Group (VG) with sufficient free capacity for the workloads.
These requirements are the minimum system requirements for MicroShift and Red Hat Enterprise Linux (RHEL). Add the system requirements for the workload you plan to run.
For example, if an IoT gateway solution requires 4 GB of RAM, your system needs to have at least 2 GB for Red Hat Enterprise Linux (RHEL) and MicroShift, plus 4 GB for the workloads. 6 GB of RAM is required in total.
It is recommended to allow for extra capacity for future needs if you are deploying physical devices in remote locations. If you are uncertain of the RAM required and if the budget permits, use the maximum RAM capacity that the device can support.
Ensure you configure secure access to the system to be able to manage it accordingly. For more information, see Using secure communications between two systems with OpenSSH.
1.2. Compatibility table
Plan to pair a supported version of RHEL for Edge with the MicroShift version you are using as described in the following compatibility table.
Red Hat Device Edge release compatibility matrix
Red Hat Enterprise Linux (RHEL) and MicroShift work together as a single solution for device-edge computing. You can update each component separately, but the product versions must be compatible. Supported configurations of Red Hat Device Edge use verified releases for each together as listed in the following table:
RHEL Version(s) | MicroShift Version | Supported MicroShift Version → Version Updates |
---|---|---|
9.4 | 4.17 | 4.17.1 → 4.17.z |
9.4 | 4.16 | 4.16.0 → 4.16.z, 4.16 → 4.17 |
9.2, 9.3 | 4.15 | 4.15.0 → 4.15.z, 4.15 → 4.16 on RHEL 9.4 |
9.2, 9.3 | 4.14 | 4.14.0 → 4.14.z, 4.14 → 4.15 or 4.14 → 4.16 on RHEL 9.4 |
1.3. MicroShift installation tools
To use MicroShift, you must already have or plan to install a RHEL type, such as on bare metal, or as a virtual machine (VM) that you provision. Although each use case has different details, each installation of Red Hat Device Edge uses RHEL tools and the OpenShift CLI (oc
).
You can use RPMs to install MicroShift on an existing RHEL machine. See Installing from an RPM package for more information. No other tools are required unless you are also installing an image-based RHEL system or VM at the same time.
1.4. RHEL installation types
Where you want to run your cluster and what your application needs to do determine the RHEL installation type that you choose. For every installation target, you must configure both the operating system and MicroShift. Consider your application storage needs, networking for cluster or application access, and your authentication and security requirements.
Understand the differences between the RHEL installation types, including the support scope of each, and the tools used.
1.4.1. Using RPMs, or package-based installation
This simple installation type uses a basic command to install MicroShift on an existing RHEL machine. See Installing from an RPM package for more information. No other tools are required unless you are also installing a RHEL system or virtual machine (VM) at the same time.
1.4.2. RHEL image-based installations
Image-based installation types involve creating an rpm-ostree
-based, immutable version of RHEL that is optimized for edge deployment.
- RHEL for Edge can be deployed to the edge in production environments. This installation type can be used where network connections are present or completely offline, depending on the local environment.
- Image mode for RHEL is available with the Technology Preview support scope. This image-based installation type is based on OCI container images and bootable containers. See bootc: Getting started with bootable containers for an introduction to bootc technology.
When choosing an image-based installation, consider whether the installation target is intended to be in an offline or networked state, where you plan to build system images, and how you plan to load your Red Hat Device Edge. Use the following scenarios as general guidance:
- If you build either a fully self-contained RHEL for Edge or an image mode for RHEL ISO outside a disconnected environment, and then install the ISO locally on your edge devices, you likely do not need an RPM repository or a mirror registry.
- If you build an ISO outside a disconnected environment that does not include the container images, but consists of only the RPMs, you need a mirror registry inside your disconnected environment. You use your mirror registry to pull container images.
- If you build images inside a disconnected environment, or use package mode for installations, you need both a mirror registry and a local RPM mirror repository. You can use either the RHEL reposync utility or Red Hat Satellite for advanced use cases. See How to create a local mirror of the latest update for Red Hat Enterprise Linux 8 and 9 without using Satellite Server and Red Hat Satellite for more information.
1.5. RHEL installation tools and concepts
Familiarize yourself with the following RHEL tools and concepts:
- A Kickstart file, which contains the configuration and instructions used during the installation of your specific operating system.
RHEL image builder is a tool for creating deployment-ready customized system images. RHEL image builder uses a blueprint that you create to make the ISO. RHEL image builder is best installed on a RHEL VM and is built with the
composer-cli
tool. To set up these tools and review the workflow, see the following RHEL documentation links:- A blueprint file directs RHEL image builder to the items to include in the ISO. An image blueprint provides a persistent definition of image customizations. You can create multiple builds from a single blueprint. You can also edit an existing blueprint to build a new ISO as requirements change. For more information, see Creating a blueprint by using the command-line interface in the RHEL documentation.
An ISO, which is the bootable operating system on which MicroShift runs.
1.6. Red Hat Device Edge installation steps
For most installation types, you must also take the following steps:
- Download the pull secret from the Red Hat Hybrid Cloud Console.
- Be ready to configure MicroShift by adding parameters and values to the MicroShift YAML configuration file. See Using the MicroShift configuration file for more information.
Decide whether you need to configure storage for the application and tasks you are using in your MicroShift cluster, or disable the MicroShift storage plug-in completely.
- For more information about creating volume groups and persistent volumes on RHEL, see Overview of logical volume management.
- For more information about the MicroShift plug-in, see Dynamic storage using the LVMS plugin.
Configure networking settings according to the access needs you plan for your MicroShift cluster and applications. Consider whether you want to use single or dual-stack networks, configure a firewall, or configure routes.
- For more information about MicroShift networking options, see Understanding networking settings.
-
Install the OpenShift CLI (
oc
) to access your cluster, see Getting started with the OpenShift CLI.
Red Hat Enterprise Linux for Real Time (real-time kernel) can be used where predictable latency is critical. Workload partitioning is also required for low-latency applications. For more information about low latency and the real-time kernel, see Configuring low latency.
Additional resources