You reviewed details about the OKD installation and update processes.
You have read the documentation on selecting a cluster installation method and preparing it for users.
You can create a single-node cluster with standard installation methods. OKD on a single node is a specialized installation that requires the creation of a special Ignition configuration file. The primary use case is for edge computing workloads, including intermittent connectivity, portable clouds, and 5G radio access networks (RAN) close to a base station. The major tradeoff with an installation on a single node is the lack of high availability.
The use of OpenShiftSDN with single-node OKD is not supported. OVN-Kubernetes is the default network plugin for single-node OKD deployments. |
Installing OKD on a single node alleviates some of the requirements for high availability and large scale clusters. However, you must address the following requirements:
Administration host: You must have a computer to prepare the ISO, to create the USB boot drive, and to monitor the installation.
For the |
ISO is not required for IBM Z® installations. |
CPU Architecture: Installing OKD on a single node supports x86_64
, arm64
,ppc64le
, and s390x
CPU architectures.
Supported platforms: Installing OKD on a single node is supported on bare metal, vSphere, AWS cloud, Red Hat OpenStack, OKD Virtualization, IBM Power®, and IBM Z® platforms.
Production-grade server: Installing OKD on a single node requires a server with sufficient resources to run OKD services and a production workload.
Profile | vCPU | Memory | Storage |
---|---|---|---|
Minimum |
8 vCPU cores |
16 GB of RAM |
120 GB |
|
The server must have a Baseboard Management Controller (BMC) when booting with virtual media.
BMC is not supported on IBM Z® and IBM Power®. |
Networking: The server must have access to the internet or access to a local registry if it is not connected to a routable network. The server must have a DHCP reservation or a static IP address for the Kubernetes API, ingress route, and cluster node domain names. You must configure the DNS to resolve the IP address to each of the following fully qualified domain names (FQDN):
Usage | FQDN | Description |
---|---|---|
Kubernetes API |
|
Add a DNS A/AAAA or CNAME record. This record must be resolvable by clients external to the cluster. |
Internal API |
|
Add a DNS A/AAAA or CNAME record when creating the ISO manually. This record must be resolvable by nodes within the cluster. |
Ingress route |
|
Add a wildcard DNS A/AAAA or CNAME record that targets the node. This record must be resolvable by clients external to the cluster. |
Without persistent IP addresses, communications between the apiserver
and etcd
might fail.