Chapter 2. Installing OpenShift on a single node You can install single-node OpenShift by using either the web-based Assisted Installer or the coreos-installer tool to generate a discovery ISO image. The discovery ISO image writes the Red Hat Enterprise Linux CoreOS (RHCOS) system configuration to the target installation disk, so that you can run a single-cluster node to meet your needs. Consider using single-node OpenShift when you want to run a cluster in a low-resource or an isolated environment for testing, troubleshooting, training, or small-scale project purposes. 2.1. Installing single-node OpenShift using the Assisted Installer To install OpenShift Container Platform on a single node, use the web-based Assisted Installer wizard to guide you through the process and manage the installation. See the Assisted Installer for OpenShift Container Platform documentation for details and configuration options. 2.1.1. Generating the discovery ISO with the Assisted Installer Installing OpenShift Container Platform on a single node requires a discovery ISO, which the Assisted Installer can generate. Procedure On the administration host, open a browser and navigate to Red Hat OpenShift Cluster Manager . Click Create New Cluster to create a new cluster. In the Cluster name field, enter a name for the cluster. In the Base domain field, enter a base domain. For example: All DNS records must be subdomains of this base domain and include the cluster name, for example: Note You cannot change the base domain or cluster name after cluster installation. Select Install single node OpenShift (SNO) and complete the rest of the wizard steps. Download the discovery ISO. Complete the remaining Assisted Installer wizard steps. Important Ensure that you take note of the discovery ISO URL for installing with virtual media. If you enable OpenShift Virtualization during this process, you must have a second local storage device of at least 50GiB for your virtual machines. Additional resources Persistent storage using logical volume manager storage What you can do with OpenShift Virtualization 2.1.2. Installing single-node OpenShift with the Assisted Installer Use the Assisted Installer to install the single-node cluster. Prerequisites Ensure that the boot drive order in the server BIOS settings defaults to booting the server from the target installation disk. Procedure Attach the discovery ISO image to the target host. Boot the server from the discovery ISO image. The discovery ISO image writes the system configuration to the target installation disk and automatically triggers a server restart. On the administration host, return to the browser. Wait for the host to appear in the list of discovered hosts. If necessary, reload the Assisted Clusters page and select the cluster name. Complete the install wizard steps. Add networking details, including a subnet from the available subnets. Add the SSH public key if necessary. Monitor the installation's progress. Watch the cluster events. After the installation process finishes writing the operating system image to the server's hard disk, the server restarts. Optional: Remove the discovery ISO image. The server restarts several times automatically, deploying the control plane. Additional resources Creating a bootable ISO image on a USB drive Booting from an HTTP-hosted ISO image using the Redfish API Adding worker nodes to single-node OpenShift clusters 2.2. Installing single-node OpenShift manually To install OpenShift Container Platform on a single node, first generate the installation ISO, and then boot the server from the ISO. You can monitor the installation using the openshift-install installation program. Additional resources Networking requirements for user-provisioned infrastructure User-provisioned DNS requirements Configuring DHCP or static IP addresses 2.2.1. Generating the installation ISO with coreos-installer Installing OpenShift Container Platform on a single node requires an installation ISO, which you can generate with the following procedure. Prerequisites Install podman . Note See "Requirements for installing OpenShift on a single node" for networking requirements, including DNS records. Procedure Set the OpenShift Container Platform version: USD export OCP_VERSION=<ocp_version> 1 1 Replace <ocp_version> with the current version, for example, latest-4.14 Set the host architecture: USD export ARCH=<architecture> 1 1 Replace <architecture> with the target host architecture, for example, aarch64 or x86_64 . Download the OpenShift Container Platform client ( oc ) and make it available for use by entering the following commands: USD curl -k https://mirror.openshift.com/pub/openshift-v4/clients/ocp/USDOCP_VERSION/openshift-client-linux.tar.gz -o oc.tar.gz USD tar zxf oc.tar.gz USD chmod +x oc Download the OpenShift Container Platform installer and make it available for use by entering the following commands: USD curl -k https://mirror.openshift.com/pub/openshift-v4/clients/ocp/USDOCP_VERSION/openshift-install-linux.tar.gz -o openshift-install-linux.tar.gz USD tar zxvf openshift-install-linux.tar.gz USD chmod +x openshift-install Retrieve the RHCOS ISO URL by running the following command: USD export ISO_URL=USD(./openshift-install coreos print-stream-json | grep location | grep USDARCH | grep iso | cut -d\" -f4) Download the RHCOS ISO: USD curl -L USDISO_URL -o rhcos-live.iso Prepare the install-config.yaml file: apiVersion: v1 baseDomain: <domain> 1 compute: - name: worker replicas: 0 2 controlPlane: name: master replicas: 1 3 metadata: name: <name> 4 networking: 5 clusterNetwork: - cidr: 10.128.0.0/14 hostPrefix: 23 machineNetwork: - cidr: 10.0.0.0/16 6 networkType: OVNKubernetes serviceNetwork: - 172.30.0.0/16 platform: none: {} bootstrapInPlace: installationDisk: /dev/disk/by-id/<disk_id> 7 pullSecret: '<pull_secret>' 8 sshKey: | <ssh_key> 9 1 Add the cluster domain name. 2 Set the compute replicas to 0 . This makes the control plane node schedulable. 3 Set the controlPlane replicas to 1 . In conjunction with the compute setting, this setting ensures the cluster runs on a single node. 4 Set the metadata name to the cluster name. 5 Set the networking details. OVN-Kubernetes is the only allowed network plugin type for single-node clusters. 6 Set the cidr value to match the subnet of the single-node OpenShift cluster. 7 Set the path to the installation disk drive, for example, /dev/disk/by-id/wwn-0x64cd98f04fde100024684cf3034da5c2 . 8 Copy the pull secret from Red Hat OpenShift Cluster Manager and add the contents to this configuration setting. 9 Add the public SSH key from the administration host so that you can log in to the cluster after installation. Generate OpenShift Container Platform assets by running the following commands: USD mkdir ocp USD cp install-config.yaml ocp USD ./openshift-install --dir=ocp create single-node-ignition-config Embed the ignition data into the RHCOS ISO by running the following commands: USD alias coreos-installer='podman run --privileged --pull always --rm \ -v /dev:/dev -v /run/udev:/run/udev -v USDPWD:/data \ -w /data quay.io/coreos/coreos-installer:release' USD coreos-installer iso ignition embed -fi ocp/bootstrap-in-place-for-live-iso.ign rhcos-live.iso Additional resources See Requirements for installing OpenShift on a single node for more information about installing OpenShift Container Platform on a single node. See Enabling cluster capabilities for more information about enabling cluster capabilities that were disabled prior to installation. See Optional cluster capabilities in OpenShift Container Platform 4.14 for more information about the features provided by each capability. 2.2.2. Monitoring the cluster installation using openshift-install Use openshift-install to monitor the progress of the single-node cluster installation. Prerequisites Ensure that the boot drive order in the server BIOS settings defaults to booting the server from the target installation disk. Procedure Attach the discovery ISO image to the target host. Boot the server from the discovery ISO image. The discovery ISO image writes the system configuration to the target installation disk and automatically triggers a server restart. On the administration host, monitor the installation by running the following command: USD ./openshift-install --dir=ocp wait-for install-complete Optional: Remove the discovery ISO image. The server restarts several times while deploying the control plane. Verification After the installation is complete, check the environment by running the following command: USD export KUBECONFIG=ocp/auth/kubeconfig USD oc get nodes Example output NAME STATUS ROLES AGE VERSION control-plane.example.com Ready master,worker 10m v1.27.3 Additional resources Creating a bootable ISO image on a USB drive Booting from an HTTP-hosted ISO image using the Redfish API Adding worker nodes to single-node OpenShift clusters 2.3. Installing single-node OpenShift on cloud providers 2.3.1. Additional requirements for installing single-node OpenShift on a cloud provider The documentation for installer-provisioned installation on cloud providers is based on a high availability cluster consisting of three control plane nodes. When referring to the documentation, consider the differences between the requirements for a single-node OpenShift cluster and a high availability cluster. A high availability cluster requires a temporary bootstrap machine, three control plane machines, and at least two compute machines. For a single-node OpenShift cluster, you need only a temporary bootstrap machine and one cloud instance for the control plane node and no compute nodes. The minimum resource requirements for high availability cluster installation include a control plane node with 4 vCPUs and 100GB of storage. For a single-node OpenShift cluster, you must have a minimum of 8 vCPUs and 120GB of storage. The controlPlane.replicas setting in the install-config.yaml file should be set to 1 . The compute.replicas setting in the install-config.yaml file should be set to 0 . This makes the control plane node schedulable. 2.3.2. Supported cloud providers for single-node OpenShift The following table contains a list of supported cloud providers and CPU architectures. Table 2.1. Supported cloud providers Cloud provider CPU architecture Amazon Web Service (AWS) x86_64 and AArch64 Microsoft Azure x86_64 Google Cloud Platform (GCP) x86_64 and AArch64 2.3.3. Installing single-node OpenShift on AWS Installing a single-node cluster on AWS requires installer-provisioned installation using the "Installing a cluster on AWS with customizations" procedure. Additional resources Installing a cluster on AWS with customizations 2.3.4. Installing single-node OpenShift on Azure Installing a single node cluster on Azure requires installer-provisioned installation using the "Installing a cluster on Azure with customizations" procedure. Additional resources Installing a cluster on Azure with customizations 2.3.5. Installing single-node OpenShift on GCP Installing a single node cluster on GCP requires installer-provisioned installation using the "Installing a cluster on GCP with customizations" procedure. Additional resources Installing a cluster on GCP with customizations 2.4. Creating a bootable ISO image on a USB drive You can install software using a bootable USB drive that contains an ISO image. Booting the server with the USB drive prepares the server for the software installation. Procedure On the administration host, insert a USB drive into a USB port. Create a bootable USB drive, for example: # dd if=<path_to_iso> of=<path_to_usb> status=progress where: <path_to_iso> is the relative path to the downloaded ISO file, for example, rhcos-live.iso . <path_to_usb> is the location of the connected USB drive, for example, /dev/sdb . After the ISO is copied to the USB drive, you can use the USB drive to install software on the server. 2.5. Booting from an HTTP-hosted ISO image using the Redfish API You can provision hosts in your network using ISOs that you install using the Redfish Baseboard Management Controller (BMC) API. Note This example procedure demonstrates the steps on a Dell server. Important Ensure that you have the latest firmware version of iDRAC that is compatible with your hardware. If you have any issues with the hardware or firmware, you must contact the provider. Prerequisites Download the installation Red Hat Enterprise Linux CoreOS (RHCOS) ISO. Use a Dell PowerEdge server that is compatible with iDRAC9. Procedure Copy the ISO file to an HTTP server accessible in your network. Boot the host from the hosted ISO file, for example: Call the Redfish API to set the hosted ISO as the VirtualMedia boot media by running the following command: USD curl -k -u <bmc_username>:<bmc_password> -d '{"Image":"<hosted_iso_file>", "Inserted": true}' -H "Content-Type: application/json" -X POST <host_bmc_address>/redfish/v1/Managers/iDRAC.Embedded.1/VirtualMedia/CD/Actions/VirtualMedia.InsertMedia Where: <bmc_username>:<bmc_password> Is the username and password for the target host BMC. <hosted_iso_file> Is the URL for the hosted installation ISO, for example: http://webserver.example.com/rhcos-live-minimal.iso . The ISO must be accessible from the target host machine. <host_bmc_address> Is the BMC IP address of the target host machine. Set the host to boot from the VirtualMedia device by running the following command: USD curl -k -u <bmc_username>:<bmc_password> -X PATCH -H 'Content-Type: application/json' -d '{"Boot": {"BootSourceOverrideTarget": "Cd", "BootSourceOverrideMode": "UEFI", "BootSourceOverrideEnabled": "Once"}}' <host_bmc_address>/redfish/v1/Systems/System.Embedded.1 Reboot the host: USD curl -k -u <bmc_username>:<bmc_password> -d '{"ResetType": "ForceRestart"}' -H 'Content-type: application/json' -X POST <host_bmc_address>/redfish/v1/Systems/System.Embedded.1/Actions/ComputerSystem.Reset Optional: If the host is powered off, you can boot it using the {"ResetType": "On"} switch. Run the following command: USD curl -k -u <bmc_username>:<bmc_password> -d '{"ResetType": "On"}' -H 'Content-type: application/json' -X POST <host_bmc_address>/redfish/v1/Systems/System.Embedded.1/Actions/ComputerSystem.Reset 2.6. Creating a custom live RHCOS ISO for remote server access In some cases, you cannot attach an external disk drive to a server, however, you need to access the server remotely to provision a node. It is recommended to enable SSH access to the server. You can create a live RHCOS ISO with SSHd enabled and with predefined credentials so that you can access the server after it boots. Prerequisites You installed the butane utility. Procedure Download the coreos-installer binary from the coreos-installer image mirror page. Download the latest live RHCOS ISO from mirror.openshift.com . Create the embedded.yaml file that the butane utility uses to create the Ignition file: variant: openshift version: 4.14.0 metadata: name: sshd labels: machineconfiguration.openshift.io/role: worker passwd: users: - name: core 1 ssh_authorized_keys: - '<ssh_key>' 1 The core user has sudo privileges. Run the butane utility to create the Ignition file using the following command: USD butane -pr embedded.yaml -o embedded.ign After the Ignition file is created, you can include the configuration in a new live RHCOS ISO, which is named rhcos-sshd-4.14.0-x86_64-live.x86_64.iso , with the coreos-installer utility: USD coreos-installer iso ignition embed -i embedded.ign rhcos-4.14.0-x86_64-live.x86_64.iso -o rhcos-sshd-4.14.0-x86_64-live.x86_64.iso Verification Check that the custom live ISO can be used to boot the server by running the following command: # coreos-installer iso ignition show rhcos-sshd-4.14.0-x86_64-live.x86_64.iso Example output { "ignition": { "version": "3.2.0" }, "passwd": { "users": [ { "name": "core", "sshAuthorizedKeys": [ "ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQCZnG8AIzlDAhpyENpK2qKiTT8EbRWOrz7NXjRzopbPu215mocaJgjjwJjh1cYhgPhpAp6M/ttTk7I4OI7g4588Apx4bwJep6oWTU35LkY8ZxkGVPAJL8kVlTdKQviDv3XX12l4QfnDom4tm4gVbRH0gNT1wzhnLP+LKYm2Ohr9D7p9NBnAdro6k++XWgkDeijLRUTwdEyWunIdW1f8G0Mg8Y1Xzr13BUo3+8aey7HLKJMDtobkz/C8ESYA/f7HJc5FxF0XbapWWovSSDJrr9OmlL9f4TfE+cQk3s+eoKiz2bgNPRgEEwihVbGsCN4grA+RzLCAOpec+2dTJrQvFqsD alosadag@sonnelicht.local" ] } ] } } 2.7. Installing single-node OpenShift with IBM Z and IBM LinuxONE Installing a single-node cluster on IBM Z(R) and IBM(R) LinuxONE requires user-provisioned installation using either the "Installing a cluster with RHEL KVM on IBM Z(R) and IBM(R) LinuxONE" or the "Installing a cluster with z/VM on IBM Z(R) and IBM(R) LinuxONE" procedure. Note Installing a single-node cluster on IBM Z(R) simplifies installation for development and test environments and requires less resource requirements at entry level. Hardware requirements The equivalent of two Integrated Facilities for Linux (IFL), which are SMT2 enabled, for each cluster. At least one network connection to both connect to the LoadBalancer service and to serve data for traffic outside the cluster. Note You can use dedicated or shared IFLs to assign sufficient compute resources. Resource sharing is one of the key strengths of IBM Z(R). However, you must adjust capacity correctly on each hypervisor layer and ensure sufficient resources for every OpenShift Container Platform cluster. Additional resources Installing a cluster with z/VM on IBM Z(R) and IBM(R) LinuxONE Installing a cluster with RHEL KVM on IBM Z(R) andIBM(R) LinuxONE 2.7.1. Installing single-node OpenShift with z/VM on IBM Z and IBM LinuxONE Prerequisites You have installed podman . Procedure Set the OpenShift Container Platform version by running the following command: USD OCP_VERSION=<ocp_version> 1 1 Replace <ocp_version> with the current version, for example, latest-4.14 Set the host architecture by running the following command: USD ARCH=<architecture> 1 1 Replace <architecture> with the target host architecture s390x . Download the OpenShift Container Platform client ( oc ) and make it available for use by entering the following commands: USD curl -k https://mirror.openshift.com/pub/openshift-v4/USD{ARCH}/clients/ocp/USD{OCP_VERSION}/openshift-client-linux.tar.gz -o oc.tar.gz USD tar zxf oc.tar.gz USD chmod +x oc Download the OpenShift Container Platform installer and make it available for use by entering the following commands: USD curl -k https://mirror.openshift.com/pub/openshift-v4/USD{ARCH}/clients/ocp/USD{OCP_VERSION}/openshift-install-linux.tar.gz -o openshift-install-linux.tar.gz USD tar zxvf openshift-install-linux.tar.gz USD chmod +x openshift-install Prepare the install-config.yaml file: apiVersion: v1 baseDomain: <domain> 1 compute: - name: worker replicas: 0 2 controlPlane: name: master replicas: 1 3 metadata: name: <name> 4 networking: 5 clusterNetwork: - cidr: 10.128.0.0/14 hostPrefix: 23 machineNetwork: - cidr: 10.0.0.0/16 6 networkType: OVNKubernetes serviceNetwork: - 172.30.0.0/16 platform: none: {} bootstrapInPlace: installationDisk: /dev/disk/by-id/<disk_id> 7 pullSecret: '<pull_secret>' 8 sshKey: | <ssh_key> 9 1 Add the cluster domain name. 2 Set the compute replicas to 0 . This makes the control plane node schedulable. 3 Set the controlPlane replicas to 1 . In conjunction with the compute setting, this setting ensures the cluster runs on a single node. 4 Set the metadata name to the cluster name. 5 Set the networking details. OVN-Kubernetes is the only allowed network plugin type for single-node clusters. 6 Set the cidr value to match the subnet of the single-node OpenShift cluster. 7 Set the path to the installation disk drive, for example, /dev/disk/by-id/wwn-0x64cd98f04fde100024684cf3034da5c2 . 8 Copy the pull secret from Red Hat OpenShift Cluster Manager and add the contents to this configuration setting. 9 Add the public SSH key from the administration host so that you can log in to the cluster after installation. Generate OpenShift Container Platform assets by running the following commands: USD mkdir ocp USD cp install-config.yaml ocp USD ./openshift-install --dir=ocp create single-node-ignition-config Obtain the RHEL kernel , initramfs , and rootfs artifacts from the Product Downloads page on the Red Hat Customer Portal or from the RHCOS image mirror page. Important The RHCOS images might not change with every release of OpenShift Container Platform. You must download images with the highest version that is less than or equal to the OpenShift Container Platform version that you install. Only use the appropriate kernel , initramfs , and rootfs artifacts described in the following procedure. The file names contain the OpenShift Container Platform version number. They resemble the following examples: kernel rhcos-<version>-live-kernel-<architecture> initramfs rhcos-<version>-live-initramfs.<architecture>.img rootfs rhcos-<version>-live-rootfs.<architecture>.img Note The rootfs image is the same for FCP and DASD. Move the following artifacts and files to an HTTP or HTTPS server: Downloaded RHEL live kernel , initramfs , and rootfs artifacts Ignition files Create parameter files for a particular virtual machine: Example parameter file rd.neednet=1 \ console=ttysclp0 \ coreos.live.rootfs_url=<rhcos_liveos>:8080/rootfs.img \ 1 ignition.firstboot ignition.platform.id=metal \ ignition.config.url=<rhcos_ign>:8080/ignition/bootstrap-in-place-for-live-iso.ign \ 2 ip=encbdd0:dhcp::02:00:00:02:34:02 3 rd.znet=qeth,0.0.bdd0,0.0.bdd1,0.0.bdd2,layer2=1 \ rd.dasd=0.0.4411 \ 4 rd.zfcp=0.0.8001,0x50050763040051e3,0x4000406300000000 \ 5 zfcp.allow_lun_scan=0 \ rd.luks.options=discard 1 For the coreos.live.rootfs_url= artifact, specify the matching rootfs artifact for the kernel`and `initramfs you are booting. Only HTTP and HTTPS protocols are supported. 2 For the ignition.config.url= parameter, specify the Ignition file for the machine role. Only HTTP and HTTPS protocols are supported. 3 For the ip= parameter, assign the IP address automatically using DHCP or manually as described in "Installing a cluster with z/VM on IBM Z(R) and IBM(R) LinuxONE". 4 For installations on DASD-type disks, use rd.dasd= to specify the DASD where RHCOS is to be installed. Omit this entry for FCP-type disks. 5 For installations on FCP-type disks, use rd.zfcp=<adapter>,<wwpn>,<lun> to specify the FCP disk where RHCOS is to be installed. Omit this entry for DASD-type disks. Leave all other parameters unchanged. Transfer the following artifacts, files, and images to z/VM. For example by using FTP: kernel and initramfs artifacts Parameter files RHCOS images For details about how to transfer the files with FTP and boot from the virtual reader, see Installing under Z/VM . Punch the files to the virtual reader of the z/VM guest virtual machine that is to become your bootstrap node. Log in to CMS on the bootstrap machine. IPL the bootstrap machine from the reader by running the following command: After the first reboot of the virtual machine, run the following commands directly after one another: To boot a DASD device after first reboot, run the following commands: USD cp i <devno> clear loadparm prompt where: <devno> Specifies the device number of the boot device as seen by the guest. USD cp vi vmsg 0 <kernel_parameters> where: <kernel_parameters> Specifies a set of kernel parameters to be stored as system control program data (SCPDATA). When booting Linux, these kernel parameters are concatenated to the end of the existing kernel parameters that are used by your boot configuration. The combined parameter string must not exceed 896 characters. To boot an FCP device after first reboot, run the following commands: USD cp set loaddev portname <wwpn> lun <lun> where: <wwpn> Specifies the target port and <lun> the logical unit in hexadecimal format. USD cp set loaddev bootprog <n> where: <n> Specifies the kernel to be booted. USD cp set loaddev scpdata {APPEND|NEW} '<kernel_parameters>' where: <kernel_parameters> Specifies a set of kernel parameters to be stored as system control program data (SCPDATA). When booting Linux, these kernel parameters are concatenated to the end of the existing kernel parameters that are used by your boot configuration. The combined parameter string must not exceed 896 characters. <APPEND|NEW> Optional: Specify APPEND to append kernel parameters to existing SCPDATA. This is the default. Specify NEW to replace existing SCPDATA. Example USD cp set loaddev scpdata 'rd.zfcp=0.0.8001,0x500507630a0350a4,0x4000409D00000000 ip=encbdd0:dhcp::02:00:00:02:34:02 rd.neednet=1' To start the IPL and boot process, run the following command: USD cp i <devno> where: <devno> Specifies the device number of the boot device as seen by the guest. 2.7.2. Installing single-node OpenShift with RHEL KVM on IBM Z and IBM LinuxONE Prerequisites You have installed podman . Procedure Set the OpenShift Container Platform version by running the following command: USD OCP_VERSION=<ocp_version> 1 1 Replace <ocp_version> with the current version, for example, latest-4.14 Set the host architecture by running the following command: USD ARCH=<architecture> 1 1 Replace <architecture> with the target host architecture s390x . Download the OpenShift Container Platform client ( oc ) and make it available for use by entering the following commands: USD curl -k https://mirror.openshift.com/pub/openshift-v4/USD{ARCH}/clients/ocp/USD{OCP_VERSION}/openshift-client-linux.tar.gz -o oc.tar.gz USD tar zxf oc.tar.gz USD chmod +x oc Download the OpenShift Container Platform installer and make it available for use by entering the following commands: USD curl -k https://mirror.openshift.com/pub/openshift-v4/USD{ARCH}/clients/ocp/USD{OCP_VERSION}/openshift-install-linux.tar.gz -o openshift-install-linux.tar.gz USD tar zxvf openshift-install-linux.tar.gz USD chmod +x openshift-install Prepare the install-config.yaml file: apiVersion: v1 baseDomain: <domain> 1 compute: - name: worker replicas: 0 2 controlPlane: name: master replicas: 1 3 metadata: name: <name> 4 networking: 5 clusterNetwork: - cidr: 10.128.0.0/14 hostPrefix: 23 machineNetwork: - cidr: 10.0.0.0/16 6 networkType: OVNKubernetes serviceNetwork: - 172.30.0.0/16 platform: none: {} bootstrapInPlace: installationDisk: /dev/disk/by-id/<disk_id> 7 pullSecret: '<pull_secret>' 8 sshKey: | <ssh_key> 9 1 Add the cluster domain name. 2 Set the compute replicas to 0 . This makes the control plane node schedulable. 3 Set the controlPlane replicas to 1 . In conjunction with the compute setting, this setting ensures the cluster runs on a single node. 4 Set the metadata name to the cluster name. 5 Set the networking details. OVN-Kubernetes is the only allowed network plugin type for single-node clusters. 6 Set the cidr value to match the subnet of the single-node OpenShift cluster. 7 Set the path to the installation disk drive, for example, /dev/disk/by-id/wwn-0x64cd98f04fde100024684cf3034da5c2 . 8 Copy the pull secret from Red Hat OpenShift Cluster Manager and add the contents to this configuration setting. 9 Add the public SSH key from the administration host so that you can log in to the cluster after installation. Generate OpenShift Container Platform assets by running the following commands: USD mkdir ocp USD cp install-config.yaml ocp USD ./openshift-install --dir=ocp create single-node-ignition-config Obtain the RHEL kernel , initramfs , and rootfs artifacts from the Product Downloads page on the Red Hat Customer Portal or from the RHCOS image mirror page. Important The RHCOS images might not change with every release of OpenShift Container Platform. You must download images with the highest version that is less than or equal to the OpenShift Container Platform version that you install. Only use the appropriate kernel , initramfs , and rootfs artifacts described in the following procedure. The file names contain the OpenShift Container Platform version number. They resemble the following examples: kernel rhcos-<version>-live-kernel-<architecture> initramfs rhcos-<version>-live-initramfs.<architecture>.img rootfs rhcos-<version>-live-rootfs.<architecture>.img Before you launch virt-install , move the following files and artifacts to an HTTP or HTTPS server: Downloaded RHEL live kernel , initramfs , and rootfs artifacts Ignition files Create the KVM guest nodes by using the following components: RHEL kernel and initramfs artifacts Ignition files The new disk image Adjusted parm line arguments USD virt-install \ --name <vm_name> \ --autostart \ --memory=<memory_mb> \ --cpu host \ --vcpus <vcpus> \ --location <media_location>,kernel=<rhcos_kernel>,initrd=<rhcos_initrd> \ 1 --disk size=100 \ --network network=<virt_network_parm> \ --graphics none \ --noautoconsole \ --extra-args "ip=<ip>::<gateway>:<mask>:<hostname>::none" \ --extra-args "nameserver=<name_server>" \ --extra-args "ip=dhcp rd.neednet=1 ignition.platform.id=metal ignition.firstboot" \ --extra-args "coreos.live.rootfs_url=<rhcos_liveos>" \ 2 --extra-args "ignition.config.url=<rhcos_ign>" \ 3 --extra-args "random.trust_cpu=on rd.luks.options=discard" \ --extra-args "console=ttysclp0" \ --wait 1 For the --location parameter, specify the location of the kernel/initrd on the HTTP or HTTPS server. 2 For the coreos.live.rootfs_url= artifact, specify the matching rootfs artifact for the kernel and initramfs you are booting. Only HTTP and HTTPS protocols are supported. 3 For the ignition.config.url= parameter, specify the Ignition file for the machine role. Only HTTP and HTTPS protocols are supported. 2.8. Installing single-node OpenShift with IBM Power Installing a single-node cluster on IBM Power(R) requires user-provisioned installation using the "Installing a cluster with IBM Power(R)" procedure. Note Installing a single-node cluster on IBM Power(R) simplifies installation for development and test environments and requires less resource requirements at entry level. Hardware requirements The equivalent of two Integrated Facilities for Linux (IFL), which are SMT2 enabled, for each cluster. At least one network connection to connect to the LoadBalancer service and to serve data for traffic outside of the cluster. Note You can use dedicated or shared IFLs to assign sufficient compute resources. Resource sharing is one of the key strengths of IBM Power(R). However, you must adjust capacity correctly on each hypervisor layer and ensure sufficient resources for every OpenShift Container Platform cluster. Additional resources Installing a cluster on IBM Power(R) 2.8.1. Setting up basion for single-node OpenShift with IBM Power Prior to installing single-node OpenShift on IBM Power(R), you must set up bastion. Setting up a bastion server for single-node OpenShift on IBM Power(R) requires the configuration of the following services: PXE is used for the single-node OpenShift cluster installation. PXE requires the following services to be configured and run: DNS to define api, api-int, and *.apps DHCP service to enable PXE and assign an IP address to single-node OpenShift node HTTP to provide ignition and RHCOS rootfs image TFTP to enable PXE You must install dnsmasq to support DNS, DHCP and PXE, httpd for HTTP. Use the following procedure to configure a bastion server that meets these requirements. Procedure Use the following command to install grub2 , which is required to enable PXE for PowerVM: grub2-mknetdir --net-directory=/var/lib/tftpboot Example /var/lib/tftpboot/boot/grub2/grub.cfg file default=0 fallback=1 timeout=1 if [ USD{net_default_mac} == fa:b0:45:27:43:20 ]; then menuentry "CoreOS (BIOS)" { echo "Loading kernel" linux "/rhcos/kernel" ip=dhcp rd.neednet=1 ignition.platform.id=metal ignition.firstboot coreos.live.rootfs_url=http://192.168.10.5:8000/install/rootfs.img ignition.config.url=http://192.168.10.5:8000/ignition/sno.ign echo "Loading initrd" initrd "/rhcos/initramfs.img" } fi Use the following commands to download RHCOS image files from the mirror repo for PXE. Enter the following command to assign the RHCOS_URL variable the follow 4.12 URL: USD export RHCOS_URL=https://mirror.openshift.com/pub/openshift-v4/ppc64le/dependencies/rhcos/4.12/latest/ Enter the following command to navigate to the /var/lib/tftpboot/rhcos directory: USD cd /var/lib/tftpboot/rhcos Enter the following command to download the specified RHCOS kernel file from the URL stored in the RHCOS_URL variable: USD wget USD{RHCOS_URL}/rhcos-live-kernel-ppc64le -o kernel Enter the following command to download the RHCOS initramfs file from the URL stored in the RHCOS_URL variable: USD wget USD{RHCOS_URL}/rhcos-live-initramfs.ppc64le.img -o initramfs.img Enter the following command to navigate to the /var//var/www/html/install/ directory: USD cd /var//var/www/html/install/ Enter the following command to download, and save, the RHCOS root filesystem image file from the URL stored in the RHCOS_URL variable: USD wget USD{RHCOS_URL}/rhcos-live-rootfs.ppc64le.img -o rootfs.img To create the ignition file for a single-node OpenShift cluster, you must create the install-config.yaml file. Enter the following command to create the work directory that holds the file: USD mkdir -p ~/sno-work Enter the following command to navigate to the ~/sno-work directory: USD cd ~/sno-work Use the following sample file can to create the required install-config.yaml in the ~/sno-work directory: apiVersion: v1 baseDomain: <domain> 1 compute: - name: worker replicas: 0 2 controlPlane: name: master replicas: 1 3 metadata: name: <name> 4 networking: 5 clusterNetwork: - cidr: 10.128.0.0/14 hostPrefix: 23 machineNetwork: - cidr: 10.0.0.0/16 6 networkType: OVNKubernetes serviceNetwork: - 172.30.0.0/16 platform: none: {} bootstrapInPlace: installationDisk: /dev/disk/by-id/<disk_id> 7 pullSecret: '<pull_secret>' 8 sshKey: | <ssh_key> 9 1 Add the cluster domain name. 2 Set the compute replicas to 0 . This makes the control plane node schedulable. 3 Set the controlPlane replicas to 1 . In conjunction with the compute setting, this setting ensures that the cluster runs on a single node. 4 Set the metadata name to the cluster name. 5 Set the networking details. OVN-Kubernetes is the only allowed network plugin type for single-node clusters. 6 Set the cidr value to match the subnet of the single-node OpenShift cluster. 7 Set the path to the installation disk drive, for example, /dev/disk/by-id/wwn-0x64cd98f04fde100024684cf3034da5c2 . 8 Copy the pull secret from Red Hat OpenShift Cluster Manager and add the contents to this configuration setting. 9 Add the public SSH key from the administration host so that you can log in to the cluster after installation. Download the openshift-install image to create the ignition file and copy it to the http directory. Enter the following command to download the openshift-install-linux-4.12.0 .tar file: USD wget https://mirror.openshift.com/pub/openshift-v4/ppc64le/clients/ocp/4.12.0/openshift-install-linux-4.12.0.tar.gz Enter the following command to unpack the openshift-install-linux-4.12.0.tar.gz archive: USD tar xzvf openshift-install-linux-4.12.0.tar.gz Enter the following command to USD ./openshift-install --dir=~/sno-work create create single-node-ignition-config Enter the following command to create the ignition file: USD cp ~/sno-work/single-node-ignition-config.ign /var/www/html/ignition/sno.ign Enter the following command to restore SELinux file for the /var/www/html directory: USD restorecon -vR /var/www/html || true Bastion now has all the required files and is properly configured in order to install single-node OpenShift. 2.8.2. Installing single-node OpenShift with IBM Power Prerequisites You have set up bastion. Procedure There are two steps for the single-node OpenShift cluster installation. First the single-node OpenShift logical partition (LPAR) needs to boot up with PXE, then you need to monitor the installation progress. Use the following command to boot powerVM with netboot: USD lpar_netboot -i -D -f -t ent -m <sno_mac> -s auto -d auto -S <server_ip> -C <sno_ip> -G <gateway> <lpar_name> default_profile <cec_name> where: sno_mac Specifies the MAC address of the single-node OpenShift cluster. sno_ip Specifies the IP address of the single-node OpenShift cluster. server_ip Specifies the IP address of bastion (PXE server). gateway Specifies the Network's gateway IP. lpar_name Specifies the single-node OpenShift lpar name in HMC. cec_name Specifies the System name where the sno_lpar resides After the single-node OpenShift LPAR boots up with PXE, use the openshift-install command to monitor the progress of installation: Run the following command after the bootstrap is complete: ./openshift-install wait-for bootstrap-complete Run the following command after it returns successfully: ./openshift-install wait-for install-complete

Commands:
example.com
<cluster_name>.example.com
export OCP_VERSION=<ocp_version> 1
export ARCH=<architecture> 1
curl -k https://mirror.openshift.com/pub/openshift-v4/clients/ocp/USDOCP_VERSION/openshift-client-linux.tar.gz -o oc.tar.gz
tar zxf oc.tar.gz
chmod +x oc
curl -k https://mirror.openshift.com/pub/openshift-v4/clients/ocp/USDOCP_VERSION/openshift-install-linux.tar.gz -o openshift-install-linux.tar.gz
tar zxvf openshift-install-linux.tar.gz
chmod +x openshift-install
export ISO_URL=USD(./openshift-install coreos print-stream-json | grep location | grep USDARCH | grep iso | cut -d\" -f4)
curl -L USDISO_URL -o rhcos-live.iso
apiVersion: v1 baseDomain: <domain> 1 compute: - name: worker replicas: 0 2 controlPlane: name: master replicas: 1 3 metadata: name: <name> 4 networking: 5 clusterNetwork: - cidr: 10.128.0.0/14 hostPrefix: 23 machineNetwork: - cidr: 10.0.0.0/16 6 networkType: OVNKubernetes serviceNetwork: - 172.30.0.0/16 platform: none: {} bootstrapInPlace: installationDisk: /dev/disk/by-id/<disk_id> 7 pullSecret: '<pull_secret>' 8 sshKey: | <ssh_key> 9
mkdir ocp
cp install-config.yaml ocp
./openshift-install --dir=ocp create single-node-ignition-config
alias coreos-installer='podman run --privileged --pull always --rm -v /dev:/dev -v /run/udev:/run/udev -v USDPWD:/data -w /data quay.io/coreos/coreos-installer:release'
coreos-installer iso ignition embed -fi ocp/bootstrap-in-place-for-live-iso.ign rhcos-live.iso
./openshift-install --dir=ocp wait-for install-complete
export KUBECONFIG=ocp/auth/kubeconfig
oc get nodes
NAME STATUS ROLES AGE VERSION control-plane.example.com Ready master,worker 10m v1.27.3
dd if=<path_to_iso> of=<path_to_usb> status=progress
curl -k -u <bmc_username>:<bmc_password> -d '{"Image":"<hosted_iso_file>", "Inserted": true}' -H "Content-Type: application/json" -X POST <host_bmc_address>/redfish/v1/Managers/iDRAC.Embedded.1/VirtualMedia/CD/Actions/VirtualMedia.InsertMedia
curl -k -u <bmc_username>:<bmc_password> -X PATCH -H 'Content-Type: application/json' -d '{"Boot": {"BootSourceOverrideTarget": "Cd", "BootSourceOverrideMode": "UEFI", "BootSourceOverrideEnabled": "Once"}}' <host_bmc_address>/redfish/v1/Systems/System.Embedded.1
curl -k -u <bmc_username>:<bmc_password> -d '{"ResetType": "ForceRestart"}' -H 'Content-type: application/json' -X POST <host_bmc_address>/redfish/v1/Systems/System.Embedded.1/Actions/ComputerSystem.Reset
curl -k -u <bmc_username>:<bmc_password> -d '{"ResetType": "On"}' -H 'Content-type: application/json' -X POST <host_bmc_address>/redfish/v1/Systems/System.Embedded.1/Actions/ComputerSystem.Reset
variant: openshift version: 4.14.0 metadata: name: sshd labels: machineconfiguration.openshift.io/role: worker passwd: users: - name: core 1 ssh_authorized_keys: - '<ssh_key>'
butane -pr embedded.yaml -o embedded.ign
coreos-installer iso ignition embed -i embedded.ign rhcos-4.14.0-x86_64-live.x86_64.iso -o rhcos-sshd-4.14.0-x86_64-live.x86_64.iso
coreos-installer iso ignition show rhcos-sshd-4.14.0-x86_64-live.x86_64.iso
{ "ignition": { "version": "3.2.0" }, "passwd": { "users": [ { "name": "core", "sshAuthorizedKeys": [ "ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQCZnG8AIzlDAhpyENpK2qKiTT8EbRWOrz7NXjRzopbPu215mocaJgjjwJjh1cYhgPhpAp6M/ttTk7I4OI7g4588Apx4bwJep6oWTU35LkY8ZxkGVPAJL8kVlTdKQviDv3XX12l4QfnDom4tm4gVbRH0gNT1wzhnLP+LKYm2Ohr9D7p9NBnAdro6k++XWgkDeijLRUTwdEyWunIdW1f8G0Mg8Y1Xzr13BUo3+8aey7HLKJMDtobkz/C8ESYA/f7HJc5FxF0XbapWWovSSDJrr9OmlL9f4TfE+cQk3s+eoKiz2bgNPRgEEwihVbGsCN4grA+RzLCAOpec+2dTJrQvFqsD alosadag@sonnelicht.local" ] } ] } }
OCP_VERSION=<ocp_version> 1
ARCH=<architecture> 1
curl -k https://mirror.openshift.com/pub/openshift-v4/USD{ARCH}/clients/ocp/USD{OCP_VERSION}/openshift-client-linux.tar.gz -o oc.tar.gz
tar zxf oc.tar.gz
chmod +x oc
curl -k https://mirror.openshift.com/pub/openshift-v4/USD{ARCH}/clients/ocp/USD{OCP_VERSION}/openshift-install-linux.tar.gz -o openshift-install-linux.tar.gz
tar zxvf openshift-install-linux.tar.gz
chmod +x openshift-install
apiVersion: v1 baseDomain: <domain> 1 compute: - name: worker replicas: 0 2 controlPlane: name: master replicas: 1 3 metadata: name: <name> 4 networking: 5 clusterNetwork: - cidr: 10.128.0.0/14 hostPrefix: 23 machineNetwork: - cidr: 10.0.0.0/16 6 networkType: OVNKubernetes serviceNetwork: - 172.30.0.0/16 platform: none: {} bootstrapInPlace: installationDisk: /dev/disk/by-id/<disk_id> 7 pullSecret: '<pull_secret>' 8 sshKey: | <ssh_key> 9
mkdir ocp
cp install-config.yaml ocp
./openshift-install --dir=ocp create single-node-ignition-config
rd.neednet=1 console=ttysclp0 coreos.live.rootfs_url=<rhcos_liveos>:8080/rootfs.img \ 1 ignition.firstboot ignition.platform.id=metal ignition.config.url=<rhcos_ign>:8080/ignition/bootstrap-in-place-for-live-iso.ign \ 2 ip=encbdd0:dhcp::02:00:00:02:34:02 3 rd.znet=qeth,0.0.bdd0,0.0.bdd1,0.0.bdd2,layer2=1 rd.dasd=0.0.4411 \ 4 rd.zfcp=0.0.8001,0x50050763040051e3,0x4000406300000000 \ 5 zfcp.allow_lun_scan=0 rd.luks.options=discard
cp ipl c
cp i <devno> clear loadparm prompt
cp vi vmsg 0 <kernel_parameters>
cp set loaddev portname <wwpn> lun <lun>
cp set loaddev bootprog <n>
cp set loaddev scpdata {APPEND|NEW} '<kernel_parameters>'
cp set loaddev scpdata 'rd.zfcp=0.0.8001,0x500507630a0350a4,0x4000409D00000000 ip=encbdd0:dhcp::02:00:00:02:34:02 rd.neednet=1'
cp i <devno>
OCP_VERSION=<ocp_version> 1
ARCH=<architecture> 1
curl -k https://mirror.openshift.com/pub/openshift-v4/USD{ARCH}/clients/ocp/USD{OCP_VERSION}/openshift-client-linux.tar.gz -o oc.tar.gz
tar zxf oc.tar.gz
chmod +x oc
curl -k https://mirror.openshift.com/pub/openshift-v4/USD{ARCH}/clients/ocp/USD{OCP_VERSION}/openshift-install-linux.tar.gz -o openshift-install-linux.tar.gz
tar zxvf openshift-install-linux.tar.gz
chmod +x openshift-install
apiVersion: v1 baseDomain: <domain> 1 compute: - name: worker replicas: 0 2 controlPlane: name: master replicas: 1 3 metadata: name: <name> 4 networking: 5 clusterNetwork: - cidr: 10.128.0.0/14 hostPrefix: 23 machineNetwork: - cidr: 10.0.0.0/16 6 networkType: OVNKubernetes serviceNetwork: - 172.30.0.0/16 platform: none: {} bootstrapInPlace: installationDisk: /dev/disk/by-id/<disk_id> 7 pullSecret: '<pull_secret>' 8 sshKey: | <ssh_key> 9
mkdir ocp
cp install-config.yaml ocp
./openshift-install --dir=ocp create single-node-ignition-config
virt-install --name <vm_name> --autostart --memory=<memory_mb> --cpu host --vcpus <vcpus> --location <media_location>,kernel=<rhcos_kernel>,initrd=<rhcos_initrd> \ 1 --disk size=100 --network network=<virt_network_parm> --graphics none --noautoconsole --extra-args "ip=<ip>::<gateway>:<mask>:<hostname>::none" --extra-args "nameserver=<name_server>" --extra-args "ip=dhcp rd.neednet=1 ignition.platform.id=metal ignition.firstboot" --extra-args "coreos.live.rootfs_url=<rhcos_liveos>" \ 2 --extra-args "ignition.config.url=<rhcos_ign>" \ 3 --extra-args "random.trust_cpu=on rd.luks.options=discard" --extra-args "console=ttysclp0" --wait
grub2-mknetdir --net-directory=/var/lib/tftpboot
default=0 fallback=1 timeout=1 if [ USD{net_default_mac} == fa:b0:45:27:43:20 ]; then menuentry "CoreOS (BIOS)" { echo "Loading kernel" linux "/rhcos/kernel" ip=dhcp rd.neednet=1 ignition.platform.id=metal ignition.firstboot coreos.live.rootfs_url=http://192.168.10.5:8000/install/rootfs.img ignition.config.url=http://192.168.10.5:8000/ignition/sno.ign echo "Loading initrd" initrd "/rhcos/initramfs.img" } fi
export RHCOS_URL=https://mirror.openshift.com/pub/openshift-v4/ppc64le/dependencies/rhcos/4.12/latest/
cd /var/lib/tftpboot/rhcos
wget USD{RHCOS_URL}/rhcos-live-kernel-ppc64le -o kernel
wget USD{RHCOS_URL}/rhcos-live-initramfs.ppc64le.img -o initramfs.img
cd /var//var/www/html/install/
wget USD{RHCOS_URL}/rhcos-live-rootfs.ppc64le.img -o rootfs.img
mkdir -p ~/sno-work
cd ~/sno-work
apiVersion: v1 baseDomain: <domain> 1 compute: - name: worker replicas: 0 2 controlPlane: name: master replicas: 1 3 metadata: name: <name> 4 networking: 5 clusterNetwork: - cidr: 10.128.0.0/14 hostPrefix: 23 machineNetwork: - cidr: 10.0.0.0/16 6 networkType: OVNKubernetes serviceNetwork: - 172.30.0.0/16 platform: none: {} bootstrapInPlace: installationDisk: /dev/disk/by-id/<disk_id> 7 pullSecret: '<pull_secret>' 8 sshKey: | <ssh_key> 9
wget https://mirror.openshift.com/pub/openshift-v4/ppc64le/clients/ocp/4.12.0/openshift-install-linux-4.12.0.tar.gz
tar xzvf openshift-install-linux-4.12.0.tar.gz
./openshift-install --dir=~/sno-work create create single-node-ignition-config
cp ~/sno-work/single-node-ignition-config.ign /var/www/html/ignition/sno.ign
restorecon -vR /var/www/html || true
lpar_netboot -i -D -f -t ent -m <sno_mac> -s auto -d auto -S <server_ip> -C <sno_ip> -G <gateway> <lpar_name> default_profile <cec_name>
./openshift-install wait-for bootstrap-complete
./openshift-install wait-for install-complete