Installing a cluster on VMC in a restricted network with user-provisioned infrastructure

In OKD version 4.10, you can install a cluster on VMware vSphere infrastructure that you provision in a restricted network by deploying it to VMware Cloud (VMC) on AWS.

Once you configure your VMC environment for OKD deployment, you use the OKD installation program from the bastion management host, co-located in the VMC environment. The installation program and control plane automates the process of deploying and managing the resources needed for the OKD cluster.

Setting up VMC for vSphere

You can install OKD on VMware Cloud (VMC) on AWS hosted vSphere clusters to enable applications to be deployed and managed both on-premise and off-premise, across the hybrid cloud.

You must configure several options in your VMC environment prior to installing OKD on VMware vSphere. Ensure your VMC environment has the following prerequisites:

• Create a non-exclusive, DHCP-enabled, NSX-T network segment and subnet. Other virtual machines (VMs) can be hosted on the subnet, but at least eight IP addresses must be available for the OKD deployment.

• Configure the following firewall rules:

  • An ANY:ANY firewall rule between the installation host and the software-defined data center (SDDC) management network on port 443. This allows you to upload the Fedora CoreOS (FCOS) OVA during deployment.

  • An HTTPS firewall rule between the OKD compute network and vCenter. This connection allows OKD to communicate with vCenter for provisioning and managing nodes, persistent volume claims (PVCs), and other resources.

• You must have the following information to deploy OKD:

  • The OKD cluster name, such as vmc-prod-1.

  • The base DNS name, such as companyname.com.

  • If not using the default, the pod network CIDR and services network CIDR must be identified, which are set by default to 10.128.0.0/14 and 172.30.0.0/16, respectively. These CIDRs are used for pod-to-pod and pod-to-service communication and are not accessible externally; however, they must not overlap with existing subnets in your organization.

  • The following vCenter information:

    • vCenter hostname, username, and password

    • Datacenter name, such as SDDC-Datacenter

    • Cluster name, such as Cluster-1

    • Network name

    • Datastore name, such as WorkloadDatastore

      It is recommended to move your vSphere cluster to the VMC Compute-ResourcePool resource pool after your cluster installation is finished.

• A Linux-based host deployed to VMC as a bastion.

  • The bastion host can be Fedora or any another Linux-based host; it must have internet connectivity and the ability to upload an OVA to the ESXi hosts.

  • Download and install the OpenShift CLI tools to the bastion host.

    • The openshift-install installation program

    • The OpenShift CLI (oc) tool

VMC Sizer tool

VMware Cloud on AWS is built on top of AWS bare metal infrastructure; this is the same bare metal infrastructure which runs AWS native services. When a VMware cloud on AWS software-defined data center (SDDC) is deployed, you consume these physical server nodes and run the VMware ESXi hypervisor in a single tenant fashion. This means the physical infrastructure is not accessible to anyone else using VMC. It is important to consider how many physical hosts you will need to host your virtual infrastructure.

To determine this, VMware provides the VMC on AWS Sizer. With this tool, you can define the resources you intend to host on VMC:

• Types of workloads

• Total number of virtual machines

• Specification information such as:

  • Storage requirements

  • vCPUs

  • vRAM

  • Overcommit ratios

With these details, the sizer tool can generate a report, based on VMware best practices, and recommend your cluster configuration and the number of hosts you will need.

vSphere prerequisites

• You reviewed details about the OKD installation and update processes.

• You read the documentation on selecting a cluster installation method and preparing it for users.

• You created a registry on your mirror host and obtain the imageContentSources data for your version of OKD.

  Because the installation media is on the mirror host, you can use that computer to complete all installation steps.

• You provisioned block registry storage. For more information on persistent storage, see Understanding persistent storage.

• If you use a firewall and plan to use the Telemetry service, you configured the firewall to allow the sites that your cluster requires access to.

  Be sure to also review this site list if you are configuring a proxy.

About installations in restricted networks

In OKD 4.10, you can perform an installation that does not require an active connection to the internet to obtain software components. Restricted network installations can be completed using installer-provisioned infrastructure or user-provisioned infrastructure, depending on the cloud platform to which you are installing the cluster.

If you choose to perform a restricted network installation on a cloud platform, you still require access to its cloud APIs. Some cloud functions, like Amazon Web Service’s IAM service, require internet access, so you might still require internet access. Depending on your network, you might require less internet access for an installation on bare metal hardware or on VMware vSphere.

To complete a restricted network installation, you must create a registry that mirrors the contents of the OKD registry and contains the installation media. You can create this registry on a mirror host, which can access both the internet and your closed network, or by using other methods that meet your restrictions.

Additional limits

Clusters in restricted networks have the following additional limitations and restrictions:

• The ClusterVersion status includes an Unable to retrieve available updates error.

• By default, you cannot use the contents of the Developer Catalog because you cannot access the required image stream tags.

VMware vSphere infrastructure requirements

You must install the OKD cluster on a VMware vSphere version 6 or 7 instance that meets the requirements for the components that you use.

If you use a vSphere version 6.5 instance, consider upgrading to 6.7U3 or 7.0 before you install OKD.

VMware vSphere CSI Driver Operator requirements

The following requirements must be met in order to install the CSI Driver Operator:

• VMware vSphere version 6.7U3 or later

• Virtual machines of hardware version 15 or later

• No third-party CSI driver already installed in the cluster

If a third-party CSI driver is present in the cluster, OKD does not overwrite it. The presence of a third-party CSI driver prevents OKD from upgrading to 4.11.

Additional resources

• To remove a third-party CSI driver, see Removing a third-party vSphere CSI Driver.

• To update the hardware version for your vSphere nodes, see Updating hardware on nodes running in vSphere.

Requirements for a cluster with user-provisioned infrastructure

For a cluster that contains user-provisioned infrastructure, you must deploy all of the required machines.

This section describes the requirements for deploying OKD on user-provisioned infrastructure.

Required machines for cluster installation

The smallest OKD clusters require the following hosts:

The bootstrap and control plane machines must use Fedora CoreOS (FCOS) as the operating system. However, the compute machines can choose between Fedora CoreOS (FCOS), Fedora 8.4, or Fedora 8.5.

See Red Hat Enterprise Linux technology capabilities and limits.

Minimum resource requirements for cluster installation

Each cluster machine must meet the following minimum requirements:

1. One vCPU is equivalent to one physical core when simultaneous multithreading (SMT), or hyperthreading, is not enabled. When enabled, use the following formula to calculate the corresponding ratio: (threads per core × cores) × sockets = vCPUs.

2. OKD and Kubernetes are sensitive to disk performance, and faster storage is recommended, particularly for etcd on the control plane nodes which require a 10 ms p99 fsync duration. Note that on many cloud platforms, storage size and IOPS scale together, so you might need to over-allocate storage volume to obtain sufficient performance.

3. As with all user-provisioned installations, if you choose to use Fedora compute machines in your cluster, you take responsibility for all operating system life cycle management and maintenance, including performing system updates, applying patches, and completing all other required tasks. Use of Fedora 7 compute machines is deprecated and planned for removal in a future release of OKD 4.

Certificate signing requests management

Because your cluster has limited access to automatic machine management when you use infrastructure that you provision, you must provide a mechanism for approving cluster certificate signing requests (CSRs) after installation. The kube-controller-manager only approves the kubelet client CSRs. The machine-approver cannot guarantee the validity of a serving certificate that is requested by using kubelet credentials because it cannot confirm that the correct machine issued the request. You must determine and implement a method of verifying the validity of the kubelet serving certificate requests and approving them.

Networking requirements for user-provisioned infrastructure

All the Fedora CoreOS (FCOS) machines require networking to be configured in initramfs during boot to fetch their Ignition config files.

During the initial boot, the machines require an IP address configuration that is set either through a DHCP server or statically by providing the required boot options. After a network connection is established, the machines download their Ignition config files from an HTTP or HTTPS server. The Ignition config files are then used to set the exact state of each machine. The Machine Config Operator completes more changes to the machines, such as the application of new certificates or keys, after installation.

It is recommended to use a DHCP server for long-term management of the cluster machines. Ensure that the DHCP server is configured to provide persistent IP addresses, DNS server information, and hostnames to the cluster machines.

The Kubernetes API server must be able to resolve the node names of the cluster machines. If the API servers and worker nodes are in different zones, you can configure a default DNS search zone to allow the API server to resolve the node names. Another supported approach is to always refer to hosts by their fully-qualified domain names in both the node objects and all DNS requests.

Setting the cluster node hostnames through DHCP

On Fedora CoreOS (FCOS) machines, the hostname is set through NetworkManager. By default, the machines obtain their hostname through DHCP. If the hostname is not provided by DHCP, it is obtained through a reverse DNS lookup. Reverse DNS lookup occurs after the network has been initialized on a node and can take time to resolve. Other system services can start prior to this and detect the hostname as localhost or similar. You can avoid this by using DHCP to provide the hostname for each cluster node.

Additionally, setting the hostnames through DHCP can bypass any manual DNS record name configuration errors in environments that have a DNS split-horizon implementation.

Network connectivity requirements

You must configure the network connectivity between machines to allow OKD cluster components to communicate. Each machine must be able to resolve the hostnames of all other machines in the cluster.

This section provides details about the ports that are required.

NTP configuration for user-provisioned infrastructure

OKD clusters are configured to use a public Network Time Protocol (NTP) server by default. If you want to use a local enterprise NTP server, or if your cluster is being deployed in a disconnected network, you can configure the cluster to use a specific time server. For more information, see the documentation for Configuring chrony time service.

If a DHCP server provides NTP server information, the chrony time service on the Fedora CoreOS (FCOS) machines read the information and can sync the clock with the NTP servers.

User-provisioned DNS requirements

In OKD deployments, DNS name resolution is required for the following components:

• The Kubernetes API

• The OKD application wildcard

• The bootstrap, control plane, and compute machines

Reverse DNS resolution is also required for the Kubernetes API, the bootstrap machine, the control plane machines, and the compute machines.

DNS A/AAAA or CNAME records are used for name resolution and PTR records are used for reverse name resolution. The reverse records are important because Fedora CoreOS (FCOS) uses the reverse records to set the hostnames for all the nodes, unless the hostnames are provided by DHCP. Additionally, the reverse records are used to generate the certificate signing requests (CSR) that OKD needs to operate.

The following DNS records are required for a user-provisioned OKD cluster and they must be in place before installation. In each record, <cluster_name> is the cluster name and <base_domain> is the base domain that you specify in the install-config.yaml file. A complete DNS record takes the form: <component>.<cluster_name>.<base_domain>..

Example DNS configuration for user-provisioned clusters

This section provides A and PTR record configuration samples that meet the DNS requirements for deploying OKD on user-provisioned infrastructure. The samples are not meant to provide advice for choosing one DNS solution over another.

In the examples, the cluster name is ocp4 and the base domain is example.com.

Example DNS A record configuration for a user-provisioned cluster

The following example is a BIND zone file that shows sample A records for name resolution in a user-provisioned cluster.

Sample DNS zone database

$TTL 1W
@    IN    SOA    ns1.example.com.    root (
            2019070700    ; serial
            3H        ; refresh (3 hours)
            30M        ; retry (30 minutes)
            2W        ; expiry (2 weeks)
            1W )        ; minimum (1 week)
    IN    NS    ns1.example.com.
    IN    MX 10    smtp.example.com.
;
;
ns1.example.com.        IN    A    192.168.1.5
smtp.example.com.        IN    A    192.168.1.5
;
helper.example.com.        IN    A    192.168.1.5
helper.ocp4.example.com.    IN    A    192.168.1.5
;
api.ocp4.example.com.        IN    A    192.168.1.5 (1)
api-int.ocp4.example.com.    IN    A    192.168.1.5 (2)
;
*.apps.ocp4.example.com.    IN    A    192.168.1.5 (3)
;
bootstrap.ocp4.example.com.    IN    A    192.168.1.96 (4)
;
master0.ocp4.example.com.    IN    A    192.168.1.97 (5)
master1.ocp4.example.com.    IN    A    192.168.1.98 (5)
master2.ocp4.example.com.    IN    A    192.168.1.99 (5)
;
worker0.ocp4.example.com.    IN    A    192.168.1.11 (6)
worker1.ocp4.example.com.    IN    A    192.168.1.7 (6)
;
;EOF

Example DNS PTR record configuration for a user-provisioned cluster

The following example BIND zone file shows sample PTR records for reverse name resolution in a user-provisioned cluster.

Sample DNS zone database for reverse records

$TTL 1W
@    IN    SOA    ns1.example.com.    root (
            2019070700    ; serial
            3H        ; refresh (3 hours)
            30M        ; retry (30 minutes)
            2W        ; expiry (2 weeks)
            1W )        ; minimum (1 week)
    IN    NS    ns1.example.com.
;
5.1.168.192.in-addr.arpa.    IN    PTR    api.ocp4.example.com. (1)
5.1.168.192.in-addr.arpa.    IN    PTR    api-int.ocp4.example.com. (2)
;
96.1.168.192.in-addr.arpa.    IN    PTR    bootstrap.ocp4.example.com. (3)
;
97.1.168.192.in-addr.arpa.    IN    PTR    master0.ocp4.example.com. (4)
98.1.168.192.in-addr.arpa.    IN    PTR    master1.ocp4.example.com. (4)
99.1.168.192.in-addr.arpa.    IN    PTR    master2.ocp4.example.com. (4)
;
11.1.168.192.in-addr.arpa.    IN    PTR    worker0.ocp4.example.com. (5)
7.1.168.192.in-addr.arpa.    IN    PTR    worker1.ocp4.example.com. (5)
;
;EOF

Load balancing requirements for user-provisioned infrastructure

Before you install OKD, you must provision the API and application ingress load balancing infrastructure. In production scenarios, you can deploy the API and application ingress load balancers separately so that you can scale the load balancer infrastructure for each in isolation.

The load balancing infrastructure must meet the following requirements:

1. API load balancer: Provides a common endpoint for users, both human and machine, to interact with and configure the platform. Configure the following conditions:

   • Layer 4 load balancing only. This can be referred to as Raw TCP, SSL Passthrough, or SSL Bridge mode. If you use SSL Bridge mode, you must enable Server Name Indication (SNI) for the API routes.

   • A stateless load balancing algorithm. The options vary based on the load balancer implementation.

   Session persistence is not required for the API load balancer to function properly.

   Configure the following ports on both the front and back of the load balancers:

   Table 8. API load balancer

   Port	Back-end machines (pool members)	Internal	External	Description
   6443	Bootstrap and control plane. You remove the bootstrap machine from the load balancer after the bootstrap machine initializes the cluster control plane. You must configure the /readyz endpoint for the API server health check probe.	X	X	Kubernetes API server
   22623	Bootstrap and control plane. You remove the bootstrap machine from the load balancer after the bootstrap machine initializes the cluster control plane.	X		Machine config server

   The load balancer must be configured to take a maximum of 30 seconds from the time the API server turns off the /readyz endpoint to the removal of the API server instance from the pool. Within the time frame after /readyz returns an error or becomes healthy, the endpoint must have been removed or added. Probing every 5 or 10 seconds, with two successful requests to become healthy and three to become unhealthy, are well-tested values.

2. Application ingress load balancer: Provides an ingress point for application traffic flowing in from outside the cluster. Configure the following conditions:

   • Layer 4 load balancing only. This can be referred to as Raw TCP, SSL Passthrough, or SSL Bridge mode. If you use SSL Bridge mode, you must enable Server Name Indication (SNI) for the ingress routes.

   • A connection-based or session-based persistence is recommended, based on the options available and types of applications that will be hosted on the platform.

   If the true IP address of the client can be seen by the application ingress load balancer, enabling source IP-based session persistence can improve performance for applications that use end-to-end TLS encryption.

   Configure the following ports on both the front and back of the load balancers:

   Table 9. Application ingress load balancer

   Port	Back-end machines (pool members)	Internal	External	Description
   443	The machines that run the Ingress Controller pods, compute, or worker, by default.	X	X	HTTPS traffic
   80	The machines that run the Ingress Controller pods, compute, or worker, by default.	X	X	HTTP traffic
   1936	The worker nodes that run the Ingress Controller pods, by default. You must configure the /healthz/ready endpoint for the ingress health check probe.	X	X	HTTP traffic

Example load balancer configuration for user-provisioned clusters

This section provides an example API and application ingress load balancer configuration that meets the load balancing requirements for user-provisioned clusters. The sample is an /etc/haproxy/haproxy.cfg configuration for an HAProxy load balancer. The example is not meant to provide advice for choosing one load balancing solution over another.

Sample API and application ingress load balancer configuration

global
  log         127.0.0.1 local2
  pidfile     /var/run/haproxy.pid
  maxconn     4000
  daemon
defaults
  mode                    http
  log                     global
  option                  dontlognull
  option http-server-close
  option                  redispatch
  retries                 3
  timeout http-request    10s
  timeout queue           1m
  timeout connect         10s
  timeout client          1m
  timeout server          1m
  timeout http-keep-alive 10s
  timeout check           10s
  maxconn                 3000
frontend stats
  bind *:1936
  mode            http
  log             global
  maxconn 10
  stats enable
  stats hide-version
  stats refresh 30s
  stats show-node
  stats show-desc Stats for ocp4 cluster (1)
  stats auth admin:ocp4
  stats uri /stats
listen api-server-6443 (2)
  bind *:6443
  mode tcp
  server bootstrap bootstrap.ocp4.example.com:6443 check inter 1s backup (3)
  server master0 master0.ocp4.example.com:6443 check inter 1s
  server master1 master1.ocp4.example.com:6443 check inter 1s
  server master2 master2.ocp4.example.com:6443 check inter 1s
listen machine-config-server-22623 (4)
  bind *:22623
  mode tcp
  server bootstrap bootstrap.ocp4.example.com:22623 check inter 1s backup (3)
  server master0 master0.ocp4.example.com:22623 check inter 1s
  server master1 master1.ocp4.example.com:22623 check inter 1s
  server master2 master2.ocp4.example.com:22623 check inter 1s
listen ingress-router-443 (5)
  bind *:443
  mode tcp
  balance source
  server worker0 worker0.ocp4.example.com:443 check inter 1s
  server worker1 worker1.ocp4.example.com:443 check inter 1s
listen ingress-router-80 (6)
  bind *:80
  mode tcp
  balance source
  server worker0 worker0.ocp4.example.com:80 check inter 1s
  server worker1 worker1.ocp4.example.com:80 check inter 1s

Preparing the user-provisioned infrastructure

Before you install OKD on user-provisioned infrastructure, you must prepare the underlying infrastructure.

This section provides details about the high-level steps required to set up your cluster infrastructure in preparation for an OKD installation. This includes configuring IP networking and network connectivity for your cluster nodes, enabling the required ports through your firewall, and setting up the required DNS and load balancing infrastructure.

After preparation, your cluster infrastructure must meet the requirements outlined in the Requirements for a cluster with user-provisioned infrastructure section.

Prerequisites

• You have reviewed the OKD 4.x Tested Integrations page.

• You have reviewed the infrastructure requirements detailed in the Requirements for a cluster with user-provisioned infrastructure section.

Procedure

1. If you are using DHCP to provide the IP networking configuration to your cluster nodes, configure your DHCP service.

   1. Add persistent IP addresses for the nodes to your DHCP server configuration. In your configuration, match the MAC address of the relevant network interface to the intended IP address for each node.

   2. When you use DHCP to configure IP addressing for the cluster machines, the machines also obtain the DNS server information through DHCP. Define the persistent DNS server address that is used by the cluster nodes through your DHCP server configuration.

      If you are not using a DHCP service, you must provide the IP networking configuration and the address of the DNS server to the nodes at FCOS install time. These can be passed as boot arguments if you are installing from an ISO image. See the Installing FCOS and starting the OKD bootstrap process section for more information about static IP provisioning and advanced networking options.

   3. Define the hostnames of your cluster nodes in your DHCP server configuration. See the Setting the cluster node hostnames through DHCP section for details about hostname considerations.

      If you are not using a DHCP service, the cluster nodes obtain their hostname through a reverse DNS lookup.

2. Ensure that your network infrastructure provides the required network connectivity between the cluster components. See the Networking requirements for user-provisioned infrastructure section for details about the requirements.

3. Configure your firewall to enable the ports required for the OKD cluster components to communicate. See Networking requirements for user-provisioned infrastructure section for details about the ports that are required.

4. Setup the required DNS infrastructure for your cluster.

   1. Configure DNS name resolution for the Kubernetes API, the application wildcard, the bootstrap machine, the control plane machines, and the compute machines.

   2. Configure reverse DNS resolution for the Kubernetes API, the bootstrap machine, the control plane machines, and the compute machines.

      See the User-provisioned DNS requirements section for more information about the OKD DNS requirements.

5. Validate your DNS configuration.

   1. From your installation node, run DNS lookups against the record names of the Kubernetes API, the wildcard routes, and the cluster nodes. Validate that the IP addresses in the responses correspond to the correct components.

   2. From your installation node, run reverse DNS lookups against the IP addresses of the load balancer and the cluster nodes. Validate that the record names in the responses correspond to the correct components.

      See the Validating DNS resolution for user-provisioned infrastructure section for detailed DNS validation steps.

6. Provision the required API and application ingress load balancing infrastructure. See the Load balancing requirements for user-provisioned infrastructure section for more information about the requirements.

Validating DNS resolution for user-provisioned infrastructure

You can validate your DNS configuration before installing OKD on user-provisioned infrastructure.

Prerequisites

• You have configured the required DNS records for your user-provisioned infrastructure.

Procedure

1. From your installation node, run DNS lookups against the record names of the Kubernetes API, the wildcard routes, and the cluster nodes. Validate that the IP addresses contained in the responses correspond to the correct components.

   1. Perform a lookup against the Kubernetes API record name. Check that the result points to the IP address of the API load balancer:

      $ dig +noall +answer @<nameserver_ip> api.<cluster_name>.<base_domain> (1)

      1	Replace <nameserver_ip> with the IP address of the nameserver, <cluster_name> with your cluster name, and <base_domain> with your base domain name.

      Example output

      api.ocp4.example.com.        0    IN    A    192.168.1.5

   2. Perform a lookup against the Kubernetes internal API record name. Check that the result points to the IP address of the API load balancer:

      $ dig +noall +answer @<nameserver_ip> api-int.<cluster_name>.<base_domain>

      Example output

      api-int.ocp4.example.com.        0    IN    A    192.168.1.5

   3. Test an example *.apps.<cluster_name>.<base_domain> DNS wildcard lookup. All of the application wildcard lookups must resolve to the IP address of the application ingress load balancer:

      $ dig +noall +answer @<nameserver_ip> random.apps.<cluster_name>.<base_domain>

      Example output

      random.apps.ocp4.example.com.        0    IN    A    192.168.1.5

      In the example outputs, the same load balancer is used for the Kubernetes API and application ingress traffic. In production scenarios, you can deploy the API and application ingress load balancers separately so that you can scale the load balancer infrastructure for each in isolation.

      You can replace random with another wildcard value. For example, you can query the route to the OKD console:

      $ dig +noall +answer @<nameserver_ip> console-openshift-console.apps.<cluster_name>.<base_domain>

      Example output

      console-openshift-console.apps.ocp4.example.com. 0 IN    A 192.168.1.5

   4. Run a lookup against the bootstrap DNS record name. Check that the result points to the IP address of the bootstrap node:

      $ dig +noall +answer @<nameserver_ip> bootstrap.<cluster_name>.<base_domain>

      Example output

      bootstrap.ocp4.example.com.        0    IN    A    192.168.1.96

   5. Use this method to perform lookups against the DNS record names for the control plane and compute nodes. Check that the results correspond to the IP addresses of each node.

2. From your installation node, run reverse DNS lookups against the IP addresses of the load balancer and the cluster nodes. Validate that the record names contained in the responses correspond to the correct components.

   1. Perform a reverse lookup against the IP address of the API load balancer. Check that the response includes the record names for the Kubernetes API and the Kubernetes internal API:

      $ dig +noall +answer @<nameserver_ip> -x 192.168.1.5

      Example output

      5.1.168.192.in-addr.arpa. 0    IN    PTR    api-int.ocp4.example.com. (1)
      5.1.168.192.in-addr.arpa. 0    IN    PTR    api.ocp4.example.com. (2)

      1	Provides the record name for the Kubernetes internal API.
      2	Provides the record name for the Kubernetes API.

      A PTR record is not required for the OKD application wildcard. No validation step is needed for reverse DNS resolution against the IP address of the application ingress load balancer.

   2. Perform a reverse lookup against the IP address of the bootstrap node. Check that the result points to the DNS record name of the bootstrap node:

      $ dig +noall +answer @<nameserver_ip> -x 192.168.1.96

      Example output

      96.1.168.192.in-addr.arpa. 0    IN    PTR    bootstrap.ocp4.example.com.

   3. Use this method to perform reverse lookups against the IP addresses for the control plane and compute nodes. Check that the results correspond to the DNS record names of each node.

Generating a key pair for cluster node SSH access

During an OKD installation, you can provide an SSH public key to the installation program. The key is passed to the Fedora CoreOS (FCOS) nodes through their Ignition config files and is used to authenticate SSH access to the nodes. The key is added to the ~/.ssh/authorized_keys list for the core user on each node, which enables password-less authentication.

After the key is passed to the nodes, you can use the key pair to SSH in to the FCOS nodes as the user core. To access the nodes through SSH, the private key identity must be managed by SSH for your local user.

If you want to SSH in to your cluster nodes to perform installation debugging or disaster recovery, you must provide the SSH public key during the installation process. The ./openshift-install gather command also requires the SSH public key to be in place on the cluster nodes.

Procedure

1. If you do not have an existing SSH key pair on your local machine to use for authentication onto your cluster nodes, create one. For example, on a computer that uses a Linux operating system, run the following command:

   $ ssh-keygen -t ed25519 -N '' -f <path>/<file_name> (1)

   1	Specify the path and file name, such as ~/.ssh/id_rsa, of the new SSH key. If you have an existing key pair, ensure your public key is in the your ~/.ssh directory.

   If you plan to install an OKD cluster that uses FIPS Validated / Modules in Process cryptographic libraries on the x86_64 architecture, do not create a key that uses the ed25519 algorithm. Instead, create a key that uses the rsa or ecdsa algorithm.

2. View the public SSH key:

   $ cat <path>/<file_name>.pub

   For example, run the following to view the ~/.ssh/id_rsa.pub public key:

   $ cat ~/.ssh/id_rsa.pub

3. Add the SSH private key identity to the SSH agent for your local user, if it has not already been added. SSH agent management of the key is required for password-less SSH authentication onto your cluster nodes, or if you want to use the ./openshift-install gather command.

   On some distributions, default SSH private key identities such as ~/.ssh/id_rsa and ~/.ssh/id_dsa are managed automatically.

   1. If the ssh-agent process is not already running for your local user, start it as a background task:

      $ eval "$(ssh-agent -s)"

      Example output

      Agent pid 31874

      If your cluster is in FIPS mode, only use FIPS-compliant algorithms to generate the SSH key. The key must be either RSA or ECDSA.

4. Add your SSH private key to the ssh-agent:

   $ ssh-add <path>/<file_name> (1)

   1	Specify the path and file name for your SSH private key, such as ~/.ssh/id_rsa

   Example output

   Identity added: /home/<you>/<path>/<file_name> (<computer_name>)

Next steps

• When you install OKD, provide the SSH public key to the installation program. If you install a cluster on infrastructure that you provision, you must provide the key to the installation program.

Manually creating the installation configuration file

For user-provisioned installations of OKD, you manually generate your installation configuration file.

Prerequisites

• You have an SSH public key on your local machine to provide to the installation program. The key will be used for SSH authentication onto your cluster nodes for debugging and disaster recovery.

• You have obtained the OKD installation program and the pull secret for your cluster.

• Obtain the imageContentSources section from the output of the command to mirror the repository.

• Obtain the contents of the certificate for your mirror registry.

Procedure

1. Create an installation directory to store your required installation assets in:

   $ mkdir <installation_directory>

   You must create a directory. Some installation assets, like bootstrap X.509 certificates have short expiration intervals, so you must not reuse an installation directory. If you want to reuse individual files from another cluster installation, you can copy them into your directory. However, the file names for the installation assets might change between releases. Use caution when copying installation files from an earlier OKD version.

2. Customize the sample install-config.yaml file template that is provided and save it in the <installation_directory>.

   You must name this configuration file install-config.yaml.

   • Unless you use a registry that FCOS trusts by default, such as docker.io, you must provide the contents of the certificate for your mirror repository in the additionalTrustBundle section. In most cases, you must provide the certificate for your mirror.

   • You must include the imageContentSources section from the output of the command to mirror the repository.

     For some platform types, you can alternatively run ./openshift-install create install-config —dir <installation_directory> to generate an install-config.yaml file. You can provide details about your cluster configuration at the prompts.

3. Back up the install-config.yaml file so that you can use it to install multiple clusters.

   The install-config.yaml file is consumed during the next step of the installation process. You must back it up now.

Sample install-config.yaml file for VMware vSphere

You can customize the install-config.yaml file to specify more details about your OKD cluster’s platform or modify the values of the required parameters.

apiVersion: v1
baseDomain: example.com (1)
compute: (2)
- hyperthreading: Enabled (3)
  name: worker
  replicas: 0 (4)
controlPlane: (2)
  hyperthreading: Enabled (3)
  name: master
  replicas: 3 (5)
metadata:
  name: test (6)
platform:
  vsphere:
    vcenter: your.vcenter.server (7)
    username: username (8)
    password: password (9)
    datacenter: datacenter (10)
    defaultDatastore: datastore (11)
    folder: "/<datacenter_name>/vm/<folder_name>/<subfolder_name>" (12)
    diskType: thin (13)
pullSecret: '{"auths":{"<local_registry>": {"auth": "<credentials>","email": "you@example.com"}}}' (14)
sshKey: 'ssh-ed25519 AAAA...' (15)
additionalTrustBundle: | (16)
  -----BEGIN CERTIFICATE-----
  ZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZ
  -----END CERTIFICATE-----
imageContentSources: (17)
- mirrors:
  - <local_registry>/<local_repository_name>/release
  source: quay.io/openshift-release-dev/ocp-release
- mirrors:
  - <local_registry>/<local_repository_name>/release
  source: quay.io/openshift-release-dev/ocp-v4.0-art-dev

Configuring the cluster-wide proxy during installation

Production environments can deny direct access to the internet and instead have an HTTP or HTTPS proxy available. You can configure a new OKD cluster to use a proxy by configuring the proxy settings in the install-config.yaml file.

Prerequisites

• You have an existing install-config.yaml file.

• You reviewed the sites that your cluster requires access to and determined whether any of them need to bypass the proxy. By default, all cluster egress traffic is proxied, including calls to hosting cloud provider APIs. You added sites to the Proxy object’s spec.noProxy field to bypass the proxy if necessary.

  The Proxy object status.noProxy field is populated with the values of the networking.machineNetwork[].cidr, networking.clusterNetwork[].cidr, and networking.serviceNetwork[] fields from your installation configuration. For installations on Amazon Web Services (AWS), Google Cloud Platform (GCP), Microsoft Azure, and Red Hat OpenStack Platform (RHOSP), the Proxy object status.noProxy field is also populated with the instance metadata endpoint (169.254.169.254).

Procedure

1. Edit your install-config.yaml file and add the proxy settings. For example:

   apiVersion: v1
   baseDomain: my.domain.com
   proxy:
     httpProxy: http://<username>:<pswd>@<ip>:<port> (1)
     httpsProxy: https://<username>:<pswd>@<ip>:<port> (2)
     noProxy: example.com (3)
   additionalTrustBundle: | (4)
       -----BEGIN CERTIFICATE-----
       <MY_TRUSTED_CA_CERT>
       -----END CERTIFICATE-----
   ...

   1	A proxy URL to use for creating HTTP connections outside the cluster. The URL scheme must be http.
   2	A proxy URL to use for creating HTTPS connections outside the cluster.
   3	A comma-separated list of destination domain names, IP addresses, or other network CIDRs to exclude from proxying. Preface a domain with . to match subdomains only. For example, .y.com matches x.y.com, but not y.com. Use * to bypass the proxy for all destinations. You must include vCenter’s IP address and the IP range that you use for its machines.
   4	If provided, the installation program generates a config map that is named user-ca-bundle in the openshift-config namespace that contains one or more additional CA certificates that are required for proxying HTTPS connections. The Cluster Network Operator then creates a trusted-ca-bundle config map that merges these contents with the Fedora CoreOS (FCOS) trust bundle, and this config map is referenced in the trustedCA field of the Proxy object. The additionalTrustBundle field is required unless the proxy’s identity certificate is signed by an authority from the FCOS trust bundle.

   The installation program does not support the proxy readinessEndpoints field.

2. Save the file and reference it when installing OKD.

The installation program creates a cluster-wide proxy that is named cluster that uses the proxy settings in the provided install-config.yaml file. If no proxy settings are provided, a cluster Proxy object is still created, but it will have a nil spec.

Creating the Kubernetes manifest and Ignition config files

Because you must modify some cluster definition files and manually start the cluster machines, you must generate the Kubernetes manifest and Ignition config files that the cluster needs to configure the machines.

The installation configuration file transforms into the Kubernetes manifests. The manifests wrap into the Ignition configuration files, which are later used to configure the cluster machines.

Prerequisites

• You obtained the OKD installation program. For a restricted network installation, these files are on your mirror host.

• You created the install-config.yaml installation configuration file.

Procedure

1. Change to the directory that contains the OKD installation program and generate the Kubernetes manifests for the cluster:

   $ ./openshift-install create manifests --dir <installation_directory> (1)

   Example output

   INFO Credentials loaded from the "myprofile" profile in file "/home/myuser/.aws/credentials"
   INFO Consuming Install Config from target directory
   INFO Manifests created in: install_dir/manifests and install_dir/openshift

   1	For <installation_directory>, specify the installation directory that contains the install-config.yaml file you created.

2. Remove the Kubernetes manifest files that define the control plane machines and compute machine sets:

   $ rm -f openshift/99_openshift-cluster-api_master-machines-*.yaml openshift/99_openshift-cluster-api_worker-machineset-*.yaml

   Because you create and manage these resources yourself, you do not have to initialize them.

   • You can preserve the machine set files to create compute machines by using the machine API, but you must update references to them to match your environment.

3. Check that the mastersSchedulable parameter in the <installation_directory>/manifests/cluster-scheduler-02-config.yml Kubernetes manifest file is set to false. This setting prevents pods from being scheduled on the control plane machines:

   1. Open the <installation_directory>/manifests/cluster-scheduler-02-config.yml file.

   2. Locate the mastersSchedulable parameter and ensure that it is set to false.

   3. Save and exit the file.

4. To create the Ignition configuration files, run the following command from the directory that contains the installation program:

   $ ./openshift-install create ignition-configs --dir <installation_directory> (1)

   1	For <installation_directory>, specify the same installation directory.

   Ignition config files are created for the bootstrap, control plane, and compute nodes in the installation directory. The kubeadmin-password and kubeconfig files are created in the ./<installation_directory>/auth directory:

   .
   ├── auth
   │   ├── kubeadmin-password
   │   └── kubeconfig
   ├── bootstrap.ign
   ├── master.ign
   ├── metadata.json
   └── worker.ign

Extracting the infrastructure name

The Ignition config files contain a unique cluster identifier that you can use to uniquely identify your cluster in VMware Cloud on AWS. If you plan to use the cluster identifier as the name of your virtual machine folder, you must extract it.

Prerequisites

• You obtained the OKD installation program and the pull secret for your cluster.

• You generated the Ignition config files for your cluster.

• You installed the jq package.

Procedure

• To extract and view the infrastructure name from the Ignition config file metadata, run the following command:

  $ jq -r .infraID <installation_directory>/metadata.json (1)

  1	For <installation_directory>, specify the path to the directory that you stored the installation files in.

  Example output

  openshift-vw9j6 (1)

  1	The output of this command is your cluster name and a random string.

Installing FCOS and starting the OKD bootstrap process

To install OKD on user-provisioned infrastructure on VMware vSphere, you must install Fedora CoreOS (FCOS) on vSphere hosts. When you install FCOS, you must provide the Ignition config file that was generated by the OKD installation program for the type of machine you are installing. If you have configured suitable networking, DNS, and load balancing infrastructure, the OKD bootstrap process begins automatically after the FCOS machines have rebooted.

Prerequisites

• You have obtained the Ignition config files for your cluster.

• You have access to an HTTP server that you can access from your computer and that the machines that you create can access.

• You have created a vSphere cluster.

Procedure

1. Upload the bootstrap Ignition config file, which is named <installation_directory>/bootstrap.ign, that the installation program created to your HTTP server. Note the URL of this file.

2. Save the following secondary Ignition config file for your bootstrap node to your computer as <installation_directory>/merge-bootstrap.ign:

   {
     "ignition": {
       "config": {
         "merge": [
           {
             "source": "<bootstrap_ignition_config_url>", (1)
             "verification": {}
           }
         ]
       },
       "timeouts": {},
       "version": "3.2.0"
     },
     "networkd": {},
     "passwd": {},
     "storage": {},
     "systemd": {}
   }

   1	Specify the URL of the bootstrap Ignition config file that you hosted.

   When you create the virtual machine (VM) for the bootstrap machine, you use this Ignition config file.

3. Locate the following Ignition config files that the installation program created:

   • <installation_directory>/master.ign

   • <installation_directory>/worker.ign

   • <installation_directory>/merge-bootstrap.ign

4. Convert the Ignition config files to Base64 encoding. Later in this procedure, you must add these files to the extra configuration parameter guestinfo.ignition.config.data in your VM.

   For example, if you use a Linux operating system, you can use the base64 command to encode the files.

   $ base64 -w0 <installation_directory>/master.ign > <installation_directory>/master.64

   $ base64 -w0 <installation_directory>/worker.ign > <installation_directory>/worker.64

   $ base64 -w0 <installation_directory>/merge-bootstrap.ign > <installation_directory>/merge-bootstrap.64

   If you plan to add more compute machines to your cluster after you finish installation, do not delete these files.

5. Obtain the FCOS images from the FCOS Downloads page

6. In the vSphere Client, create a folder in your datacenter to store your VMs.

   1. Click the VMs and Templates view.

   2. Right-click the name of your datacenter.

   3. Click New Folder → New VM and Template Folder.

   4. In the window that is displayed, enter the folder name. If you did not specify an existing folder in the install-config.yaml file, then create a folder with the same name as the infrastructure ID. You use this folder name so vCenter dynamically provisions storage in the appropriate location for its Workspace configuration.

7. In the vSphere Client, create a template for the OVA image and then clone the template as needed.

   In the following steps, you create a template and then clone the template for all of your cluster machines. You then provide the location for the Ignition config file for that cloned machine type when you provision the VMs.

   1. From the Hosts and Clusters tab, right-click your cluster name and select Deploy OVF Template.

   2. On the Select an OVF tab, specify the name of the FCOS OVA file that you downloaded.

   3. On the Select a name and folder tab, set a Virtual machine name for your template, such as Template-FCOS. Click the name of your vSphere cluster and select the folder you created in the previous step.

   4. On the Select a compute resource tab, click the name of your vSphere cluster.

   5. On the Select storage tab, configure the storage options for your VM.

      • Select Thin Provision or Thick Provision, based on your storage preferences.

      • Select the datastore that you specified in your install-config.yaml file.

   6. On the Select network tab, specify the network that you configured for the cluster, if available.

   7. When creating the OVF template, do not specify values on the Customize template tab or configure the template any further.

      Do not start the original VM template. The VM template must remain off and must be cloned for new FCOS machines. Starting the VM template configures the VM template as a VM on the platform, which prevents it from being used as a template that machine sets can apply configurations to.

8. Optional: Update the configured virtual hardware version in the VM template, if necessary. Follow Upgrading a virtual machine to the latest hardware version in the VMware documentation for more information.

   It is recommended that you update the hardware version of the VM template to version 15 before creating VMs from it, if necessary. Using hardware version 13 for your cluster nodes running on vSphere is now deprecated. If your imported template defaults to hardware version 13, you must ensure that your ESXi host is on 6.7U3 or later before upgrading the VM template to hardware version 15. If your vSphere version is less than 6.7U3, you can skip this upgrade step; however, a future version of OKD is scheduled to remove support for hardware version 13 and vSphere versions less than 6.7U3.

9. After the template deploys, deploy a VM for a machine in the cluster.

   1. Right-click the template name and click Clone → Clone to Virtual Machine.

   2. On the Select a name and folder tab, specify a name for the VM. You might include the machine type in the name, such as control-plane-0 or compute-1.

      Ensure that all virtual machine names across a vSphere installation are unique.

   3. On the Select a name and folder tab, select the name of the folder that you created for the cluster.

   4. On the Select a compute resource tab, select the name of a host in your datacenter.

   5. Optional: On the Select storage tab, customize the storage options.

   6. On the Select clone options, select Customize this virtual machine’s hardware.

   7. On the Customize hardware tab, click VM Options → Advanced.

      • Optional: Override default DHCP networking in vSphere. To enable static IP networking:

        1. Set your static IP configuration:

           $ export IPCFG="ip=<ip>::<gateway>:<netmask>:<hostname>:<iface>:none nameserver=srv1 [nameserver=srv2 [nameserver=srv3 [...]]]"

           Example command

           $ export IPCFG="ip=192.168.100.101::192.168.100.254:255.255.255.0:::none nameserver=8.8.8.8"

        2. Set the guestinfo.afterburn.initrd.network-kargs property before booting a VM from an OVA in vSphere:

           $ govc vm.change -vm "<vm_name>" -e "guestinfo.afterburn.initrd.network-kargs=${IPCFG}"

      • Optional: In the event of cluster performance issues, from the Latency Sensitivity list, select High. Ensure that your VM’s CPU and memory reservation have the following values:

        • Memory reservation value must be equal to its configured memory size.

        • CPU reservation value must be at least the number of low latency virtual CPUs multiplied by the measured physical CPU speed.

      • Click Edit Configuration, and on the Configuration Parameters window, click Add Configuration Params. Define the following parameter names and values:

        • guestinfo.ignition.config.data: Locate the base-64 encoded files that you created previously in this procedure, and paste the contents of the base64-encoded Ignition config file for this machine type.

        • guestinfo.ignition.config.data.encoding: Specify base64.

        • disk.EnableUUID: Specify TRUE.

8.  In the **Virtual Hardware** panel of the **Customize hardware** tab, modify the specified values as required. Ensure that the amount of RAM, CPU, and disk storage meets the minimum requirements for the machine type.
9.  Complete the configuration and power on the VM.
10.  Check the console output to verify that Ignition ran.
    Example command
    ```
    Ignition: ran on 2022/03/14 14:48:33 UTC (this boot)
    Ignition: user-provided config was applied
    ```

1. Create the rest of the machines for your cluster by following the preceding steps for each machine.

   You must create the bootstrap and control plane machines at this time. Because some pods are deployed on compute machines by default, also create at least two compute machines before you install the cluster.

Adding more compute machines to a cluster in vSphere

You can add more compute machines to a user-provisioned OKD cluster on VMware vSphere.

Prerequisites

• Obtain the base64-encoded Ignition file for your compute machines.

• You have access to the vSphere template that you created for your cluster.

Procedure

1. After the template deploys, deploy a VM for a machine in the cluster.

   1. Right-click the template’s name and click Clone → Clone to Virtual Machine.

   2. On the Select a name and folder tab, specify a name for the VM. You might include the machine type in the name, such as compute-1.

      Ensure that all virtual machine names across a vSphere installation are unique.

   3. On the Select a name and folder tab, select the name of the folder that you created for the cluster.

   4. On the Select a compute resource tab, select the name of a host in your datacenter.

   5. Optional: On the Select storage tab, customize the storage options.

   6. On the Select clone options, select Customize this virtual machine’s hardware.

   7. On the Customize hardware tab, click VM Options → Advanced.

      • From the Latency Sensitivity list, select High.

      • Click Edit Configuration, and on the Configuration Parameters window, click Add Configuration Params. Define the following parameter names and values:

        • guestinfo.ignition.config.data: Paste the contents of the base64-encoded compute Ignition config file for this machine type.

        • guestinfo.ignition.config.data.encoding: Specify base64.

        • disk.EnableUUID: Specify TRUE.

8.  In the **Virtual Hardware** panel of the **Customize hardware** tab, modify the specified values as required. Ensure that the amount of RAM, CPU, and disk storage meets the minimum requirements for the machine type. Also, make sure to select the correct network under **Add network adapter** if there are multiple networks available.
9.  Complete the configuration and power on the VM.

1. Continue to create more compute machines for your cluster.

Disk partitioning

In most cases, data partitions are originally created by installing FCOS, rather than by installing another operating system. In such cases, the OKD installer should be allowed to configure your disk partitions.

However, there are two cases where you might want to intervene to override the default partitioning when installing an OKD node:

• Create separate partitions: For greenfield installations on an empty disk, you might want to add separate storage to a partition. This is officially supported for making /var or a subdirectory of /var, such as /var/lib/etcd, a separate partition, but not both.

  Kubernetes supports only two filesystem partitions. If you add more than one partition to the original configuration, Kubernetes cannot monitor all of them.

• Retain existing partitions: For a brownfield installation where you are reinstalling OKD on an existing node and want to retain data partitions installed from your previous operating system, there are both boot arguments and options to coreos-installer that allow you to retain existing data partitions.

Creating a separate /var partition

In general, disk partitioning for OKD should be left to the installer. However, there are cases where you might want to create separate partitions in a part of the filesystem that you expect to grow.

OKD supports the addition of a single partition to attach storage to either the /var partition or a subdirectory of /var. For example:

• /var/lib/containers: Holds container-related content that can grow as more images and containers are added to a system.

• /var/lib/etcd: Holds data that you might want to keep separate for purposes such as performance optimization of etcd storage.

• /var: Holds data that you might want to keep separate for purposes such as auditing.

Storing the contents of a /var directory separately makes it easier to grow storage for those areas as needed and reinstall OKD at a later date and keep that data intact. With this method, you will not have to pull all your containers again, nor will you have to copy massive log files when you update systems.

Because /var must be in place before a fresh installation of Fedora CoreOS (FCOS), the following procedure sets up the separate /var partition by creating a machine config manifest that is inserted during the openshift-install preparation phases of an OKD installation.

Procedure

1. Create a directory to hold the OKD installation files:

   $ mkdir $HOME/clusterconfig

2. Run openshift-install to create a set of files in the manifest and openshift subdirectories. Answer the system questions as you are prompted:

   $ openshift-install create manifests --dir $HOME/clusterconfig
   ? SSH Public Key ...
   $ ls $HOME/clusterconfig/openshift/
   99_kubeadmin-password-secret.yaml
   99_openshift-cluster-api_master-machines-0.yaml
   99_openshift-cluster-api_master-machines-1.yaml
   99_openshift-cluster-api_master-machines-2.yaml
   ...

3. Create a Butane config that configures the additional partition. For example, name the file $HOME/clusterconfig/98-var-partition.bu, change the disk device name to the name of the storage device on the worker systems, and set the storage size as appropriate. This example places the /var directory on a separate partition:

   variant: openshift
   version: 4.10.0
   metadata:
     labels:
       machineconfiguration.openshift.io/role: worker
     name: 98-var-partition
   storage:
     disks:
     - device: /dev/<device_name> (1)
       partitions:
       - label: var
         start_mib: <partition_start_offset> (2)
         size_mib: <partition_size> (3)
     filesystems:
       - device: /dev/disk/by-partlabel/var
         path: /var
         format: xfs
         mount_options: [defaults, prjquota] (4)
         with_mount_unit: true

   1	The storage device name of the disk that you want to partition.
   2	When adding a data partition to the boot disk, a minimum value of 25000 mebibytes is recommended. The root file system is automatically resized to fill all available space up to the specified offset. If no value is specified, or if the specified value is smaller than the recommended minimum, the resulting root file system will be too small, and future reinstalls of FCOS might overwrite the beginning of the data partition.
   3	The size of the data partition in mebibytes.
   4	The prjquota mount option must be enabled for filesystems used for container storage.

   When creating a separate /var partition, you cannot use different instance types for worker nodes, if the different instance types do not have the same device name.

4. Create a manifest from the Butane config and save it to the clusterconfig/openshift directory. For example, run the following command:

   $ butane $HOME/clusterconfig/98-var-partition.bu -o $HOME/clusterconfig/openshift/98-var-partition.yaml

5. Run openshift-install again to create Ignition configs from a set of files in the manifest and openshift subdirectories:

   $ openshift-install create ignition-configs --dir $HOME/clusterconfig
   $ ls $HOME/clusterconfig/
   auth  bootstrap.ign  master.ign  metadata.json  worker.ign

Now you can use the Ignition config files as input to the vSphere installation procedures to install Fedora CoreOS (FCOS) systems.

Updating the bootloader using bootupd

To update the bootloader by using bootupd, you must either install bootupd on FCOS machines manually or provide a machine config with the enabled systemd unit. Unlike grubby or other bootloader tools, bootupd does not manage kernel space configuration such as passing kernel arguments.

After you have installed bootupd, you can manage it remotely from the OKD cluster.

Manual install method

You can manually install bootupd by using the bootctl command-line tool.

1. Inspect the system status:

   # bootupctl status

   Example output for x86_64

   Component EFI
     Installed: grub2-efi-x64-1:2.04-31.fc33.x86_64,shim-x64-15-8.x86_64
     Update: At latest version

   Example output for arm64

   Component EFI
     Installed: grub2-efi-aa64-1:2.02-99.el8_4.1.aarch64,shim-aa64-15.4-2.el8_1.aarch64
     Update: At latest version

2. FCOS images created without bootupd installed on them require an explicit adoption phase.

   If the system status is Adoptable, perform the adoption:

   # bootupctl adopt-and-update

   Example output

   Updated: grub2-efi-x64-1:2.04-31.fc33.x86_64,shim-x64-15-8.x86_64

3. If an update is available, apply the update so that the changes take effect on the next reboot:

   # bootupctl update

   Example output

   Updated: grub2-efi-x64-1:2.04-31.fc33.x86_64,shim-x64-15-8.x86_64

Machine config method

Another way to enable bootupd is by providing a machine config.

• Provide a machine config file with the enabled systemd unit, as shown in the following example:

  Example output

    variant: rhcos
    version: 1.1.0
    systemd:
      units:
        - name: custom-bootupd-auto.service
          enabled: true
          contents: |
            [Unit]
            Description=Bootupd automatic update
            [Service]
            ExecStart=/usr/bin/bootupctl update
            RemainAfterExit=yes
            [Install]
            WantedBy=multi-user.target

Waiting for the bootstrap process to complete

The OKD bootstrap process begins after the cluster nodes first boot into the persistent FCOS environment that has been installed to disk. The configuration information provided through the Ignition config files is used to initialize the bootstrap process and install OKD on the machines. You must wait for the bootstrap process to complete.

Prerequisites

• You have created the Ignition config files for your cluster.

• You have configured suitable network, DNS and load balancing infrastructure.

• You have obtained the installation program and generated the Ignition config files for your cluster.

• You installed FCOS on your cluster machines and provided the Ignition config files that the OKD installation program generated.

Procedure

1. Monitor the bootstrap process:

   $ ./openshift-install --dir <installation_directory> wait-for bootstrap-complete \ (1)
       --log-level=info (2)

   1	For <installation_directory>, specify the path to the directory that you stored the installation files in.
   2	To view different installation details, specify warn, debug, or error instead of info.

   Example output

   INFO Waiting up to 30m0s for the Kubernetes API at https://api.test.example.com:6443...
   INFO API v1.23.0 up
   INFO Waiting up to 30m0s for bootstrapping to complete...
   INFO It is now safe to remove the bootstrap resources

   The command succeeds when the Kubernetes API server signals that it has been bootstrapped on the control plane machines.

2. After bootstrap process is complete, remove the bootstrap machine from the load balancer.

   You must remove the bootstrap machine from the load balancer at this point. You can also remove or reformat the bootstrap machine itself.

Logging in to the cluster by using the CLI

You can log in to your cluster as a default system user by exporting the cluster kubeconfig file. The kubeconfig file contains information about the cluster that is used by the CLI to connect a client to the correct cluster and API server. The file is specific to a cluster and is created during OKD installation.

Prerequisites

• You deployed an OKD cluster.

• You installed the oc CLI.

Procedure

1. Export the kubeadmin credentials:

   $ export KUBECONFIG=<installation_directory>/auth/kubeconfig (1)

   1	For <installation_directory>, specify the path to the directory that you stored the installation files in.

2. Verify you can run oc commands successfully using the exported configuration:

   $ oc whoami

   Example output

   system:admin

Approving the certificate signing requests for your machines

When you add machines to a cluster, two pending certificate signing requests (CSRs) are generated for each machine that you added. You must confirm that these CSRs are approved or, if necessary, approve them yourself. The client requests must be approved first, followed by the server requests.

Prerequisites

• You added machines to your cluster.

Procedure

1. Confirm that the cluster recognizes the machines:

   $ oc get nodes

   Example output

   NAME      STATUS    ROLES   AGE  VERSION
   master-0  Ready     master  63m  v1.23.0
   master-1  Ready     master  63m  v1.23.0
   master-2  Ready     master  64m  v1.23.0

   The output lists all of the machines that you created.

   The preceding output might not include the compute nodes, also known as worker nodes, until some CSRs are approved.

2. Review the pending CSRs and ensure that you see the client requests with the Pending or Approved status for each machine that you added to the cluster:

   $ oc get csr

   Example output

   NAME        AGE     REQUESTOR                                                                   CONDITION
   csr-8b2br   15m     system:serviceaccount:openshift-machine-config-operator:node-bootstrapper   Pending
   csr-8vnps   15m     system:serviceaccount:openshift-machine-config-operator:node-bootstrapper   Pending
   ...

   In this example, two machines are joining the cluster. You might see more approved CSRs in the list.

3. If the CSRs were not approved, after all of the pending CSRs for the machines you added are in Pending status, approve the CSRs for your cluster machines:

   Because the CSRs rotate automatically, approve your CSRs within an hour of adding the machines to the cluster. If you do not approve them within an hour, the certificates will rotate, and more than two certificates will be present for each node. You must approve all of these certificates. After the client CSR is approved, the Kubelet creates a secondary CSR for the serving certificate, which requires manual approval. Then, subsequent serving certificate renewal requests are automatically approved by the machine-approver if the Kubelet requests a new certificate with identical parameters.

   For clusters running on platforms that are not machine API enabled, such as bare metal and other user-provisioned infrastructure, you must implement a method of automatically approving the kubelet serving certificate requests (CSRs). If a request is not approved, then the oc exec, oc rsh, and oc logs commands cannot succeed, because a serving certificate is required when the API server connects to the kubelet. Any operation that contacts the Kubelet endpoint requires this certificate approval to be in place. The method must watch for new CSRs, confirm that the CSR was submitted by the node-bootstrapper service account in the system:node or system:admin groups, and confirm the identity of the node.

   • To approve them individually, run the following command for each valid CSR:

     $ oc adm certificate approve <csr_name> (1)

     1	<csr_name> is the name of a CSR from the list of current CSRs.

   • To approve all pending CSRs, run the following command:

     $ oc get csr -o go-template='{{range .items}}{{if not .status}}{{.metadata.name}}{{"\n"}}{{end}}{{end}}' | xargs --no-run-if-empty oc adm certificate approve

     Some Operators might not become available until some CSRs are approved.

4. Now that your client requests are approved, you must review the server requests for each machine that you added to the cluster:

   $ oc get csr

   Example output

   NAME        AGE     REQUESTOR                                                                   CONDITION
   csr-bfd72   5m26s   system:node:ip-10-0-50-126.us-east-2.compute.internal                       Pending
   csr-c57lv   5m26s   system:node:ip-10-0-95-157.us-east-2.compute.internal                       Pending
   ...

5. If the remaining CSRs are not approved, and are in the Pending status, approve the CSRs for your cluster machines:

   • To approve them individually, run the following command for each valid CSR:

     $ oc adm certificate approve <csr_name> (1)

     1	<csr_name> is the name of a CSR from the list of current CSRs.

   • To approve all pending CSRs, run the following command:

     $ oc get csr -o go-template='{{range .items}}{{if not .status}}{{.metadata.name}}{{"\n"}}{{end}}{{end}}' | xargs oc adm certificate approve

6. After all client and server CSRs have been approved, the machines have the Ready status. Verify this by running the following command:

   $ oc get nodes

   Example output

   NAME      STATUS    ROLES   AGE  VERSION
   master-0  Ready     master  73m  v1.23.0
   master-1  Ready     master  73m  v1.23.0
   master-2  Ready     master  74m  v1.23.0
   worker-0  Ready     worker  11m  v1.23.0
   worker-1  Ready     worker  11m  v1.23.0

   It can take a few minutes after approval of the server CSRs for the machines to transition to the Ready status.

Additional information

• For more information on CSRs, see Certificate Signing Requests.

Initial Operator configuration

After the control plane initializes, you must immediately configure some Operators so that they all become available.

Prerequisites

• Your control plane has initialized.

Procedure

1. Watch the cluster components come online:

   $ watch -n5 oc get clusteroperators

   Example output

   NAME                                       VERSION   AVAILABLE   PROGRESSING   DEGRADED   SINCE
   authentication                             4.10.0    True        False         False      19m
   baremetal                                  4.10.0    True        False         False      37m
   cloud-credential                           4.10.0    True        False         False      40m
   cluster-autoscaler                         4.10.0    True        False         False      37m
   config-operator                            4.10.0    True        False         False      38m
   console                                    4.10.0    True        False         False      26m
   csi-snapshot-controller                    4.10.0    True        False         False      37m
   dns                                        4.10.0    True        False         False      37m
   etcd                                       4.10.0    True        False         False      36m
   image-registry                             4.10.0    True        False         False      31m
   ingress                                    4.10.0    True        False         False      30m
   insights                                   4.10.0    True        False         False      31m
   kube-apiserver                             4.10.0    True        False         False      26m
   kube-controller-manager                    4.10.0    True        False         False      36m
   kube-scheduler                             4.10.0    True        False         False      36m
   kube-storage-version-migrator              4.10.0    True        False         False      37m
   machine-api                                4.10.0    True        False         False      29m
   machine-approver                           4.10.0    True        False         False      37m
   machine-config                             4.10.0    True        False         False      36m
   marketplace                                4.10.0    True        False         False      37m
   monitoring                                 4.10.0    True        False         False      29m
   network                                    4.10.0    True        False         False      38m
   node-tuning                                4.10.0    True        False         False      37m
   openshift-apiserver                        4.10.0    True        False         False      32m
   openshift-controller-manager               4.10.0    True        False         False      30m
   openshift-samples                          4.10.0    True        False         False      32m
   operator-lifecycle-manager                 4.10.0    True        False         False      37m
   operator-lifecycle-manager-catalog         4.10.0    True        False         False      37m
   operator-lifecycle-manager-packageserver   4.10.0    True        False         False      32m
   service-ca                                 4.10.0    True        False         False      38m
   storage                                    4.10.0    True        False         False      37m

2. Configure the Operators that are not available.

Disabling the default OperatorHub sources

Operator catalogs that source content provided by Red Hat and community projects are configured for OperatorHub by default during an OKD installation. In a restricted network environment, you must disable the default catalogs as a cluster administrator.

Procedure

• Disable the sources for the default catalogs by adding disableAllDefaultSources: true to the OperatorHub object:

  $ oc patch OperatorHub cluster --type json \
      -p '[{"op": "add", "path": "/spec/disableAllDefaultSources", "value": true}]'

Image registry storage configuration

The Image Registry Operator is not initially available for platforms that do not provide default storage. After installation, you must configure your registry to use storage so that the Registry Operator is made available.

Instructions are shown for configuring a persistent volume, which is required for production clusters. Where applicable, instructions are shown for configuring an empty directory as the storage location, which is available for only non-production clusters.

Additional instructions are provided for allowing the image registry to use block storage types by using the Recreate rollout strategy during upgrades.

Configuring registry storage for VMware vSphere

As a cluster administrator, following installation you must configure your registry to use storage.

Prerequisites

• Cluster administrator permissions.

• A cluster on VMware vSphere.

• Persistent storage provisioned for your cluster, such as Red Hat OpenShift Data Foundation.

  OKD supports ReadWriteOnce access for image registry storage when you have only one replica. To deploy an image registry that supports high availability with two or more replicas, ReadWriteMany access is required.

• Must have “100Gi” capacity.

Procedure

1. To configure your registry to use storage, change the spec.storage.pvc in the configs.imageregistry/cluster resource.

   When using shared storage, review your security settings to prevent outside access.

2. Verify that you do not have a registry pod:

   $ oc get pod -n openshift-image-registry

   If the storage type is emptyDIR, the replica number cannot be greater than 1.

3. Check the registry configuration:

   $ oc edit configs.imageregistry.operator.openshift.io

   Example output

   storage:
     pvc:
       claim: (1)

   1	Leave the claim field blank to allow the automatic creation of an image-registry-storage PVC.

4. Check the clusteroperator status:

   $ oc get clusteroperator image-registry

Configuring storage for the image registry in non-production clusters

You must configure storage for the Image Registry Operator. For non-production clusters, you can set the image registry to an empty directory. If you do so, all images are lost if you restart the registry.

Procedure

• To set the image registry storage to an empty directory:

  $ oc patch configs.imageregistry.operator.openshift.io cluster --type merge --patch '{"spec":{"storage":{"emptyDir":{}}}}'

  Configure this option for only non-production clusters.

  If you run this command before the Image Registry Operator initializes its components, the oc patch command fails with the following error:

  Error from server (NotFound): configs.imageregistry.operator.openshift.io "cluster" not found

  Wait a few minutes and run the command again.

Configuring block registry storage for VMware vSphere

To allow the image registry to use block storage types such as vSphere Virtual Machine Disk (VMDK) during upgrades as a cluster administrator, you can use the Recreate rollout strategy.

Procedure

1. To set the image registry storage as a block storage type, patch the registry so that it uses the Recreate rollout strategy and runs with only 1 replica:

   $ oc patch config.imageregistry.operator.openshift.io/cluster --type=merge -p '{"spec":{"rolloutStrategy":"Recreate","replicas":1}}'

2. Provision the PV for the block storage device, and create a PVC for that volume. The requested block volume uses the ReadWriteOnce (RWO) access mode.

   1. Create a pvc.yaml file with the following contents to define a VMware vSphere PersistentVolumeClaim object:

      kind: PersistentVolumeClaim
      apiVersion: v1
      metadata:
        name: image-registry-storage (1)
        namespace: openshift-image-registry (2)
      spec:
        accessModes:
        - ReadWriteOnce (3)
        resources:
          requests:
            storage: 100Gi (4)

      1	A unique name that represents the PersistentVolumeClaim object.
      2	The namespace for the PersistentVolumeClaim object, which is openshift-image-registry.
      3	The access mode of the persistent volume claim. With ReadWriteOnce, the volume can be mounted with read and write permissions by a single node.
      4	The size of the persistent volume claim.

   2. Create the PersistentVolumeClaim object from the file:

      $ oc create -f pvc.yaml -n openshift-image-registry

3. Edit the registry configuration so that it references the correct PVC:

   $ oc edit config.imageregistry.operator.openshift.io -o yaml

   Example output

   storage:
     pvc:
       claim: (1)

   1	Creating a custom PVC allows you to leave the claim field blank for the default automatic creation of an image-registry-storage PVC.

For instructions about configuring registry storage so that it references the correct PVC, see Configuring registry storage for VMware vSphere.

Completing installation on user-provisioned infrastructure

After you complete the Operator configuration, you can finish installing the cluster on infrastructure that you provide.

Prerequisites

• Your control plane has initialized.

• You have completed the initial Operator configuration.

Procedure

1. Confirm that all the cluster components are online with the following command:

   $ watch -n5 oc get clusteroperators

   Example output

   NAME                                       VERSION   AVAILABLE   PROGRESSING   DEGRADED   SINCE
   authentication                             4.10.0    True        False         False      19m
   baremetal                                  4.10.0    True        False         False      37m
   cloud-credential                           4.10.0    True        False         False      40m
   cluster-autoscaler                         4.10.0    True        False         False      37m
   config-operator                            4.10.0    True        False         False      38m
   console                                    4.10.0    True        False         False      26m
   csi-snapshot-controller                    4.10.0    True        False         False      37m
   dns                                        4.10.0    True        False         False      37m
   etcd                                       4.10.0    True        False         False      36m
   image-registry                             4.10.0    True        False         False      31m
   ingress                                    4.10.0    True        False         False      30m
   insights                                   4.10.0    True        False         False      31m
   kube-apiserver                             4.10.0    True        False         False      26m
   kube-controller-manager                    4.10.0    True        False         False      36m
   kube-scheduler                             4.10.0    True        False         False      36m
   kube-storage-version-migrator              4.10.0    True        False         False      37m
   machine-api                                4.10.0    True        False         False      29m
   machine-approver                           4.10.0    True        False         False      37m
   machine-config                             4.10.0    True        False         False      36m
   marketplace                                4.10.0    True        False         False      37m
   monitoring                                 4.10.0    True        False         False      29m
   network                                    4.10.0    True        False         False      38m
   node-tuning                                4.10.0    True        False         False      37m
   openshift-apiserver                        4.10.0    True        False         False      32m
   openshift-controller-manager               4.10.0    True        False         False      30m
   openshift-samples                          4.10.0    True        False         False      32m
   operator-lifecycle-manager                 4.10.0    True        False         False      37m
   operator-lifecycle-manager-catalog         4.10.0    True        False         False      37m
   operator-lifecycle-manager-packageserver   4.10.0    True        False         False      32m
   service-ca                                 4.10.0    True        False         False      38m
   storage                                    4.10.0    True        False         False      37m

   Alternatively, the following command notifies you when all of the clusters are available. It also retrieves and displays credentials:

   $ ./openshift-install --dir <installation_directory> wait-for install-complete (1)

   1	For <installation_directory>, specify the path to the directory that you stored the installation files in.

   Example output

   INFO Waiting up to 30m0s for the cluster to initialize...

   The command succeeds when the Cluster Version Operator finishes deploying the OKD cluster from Kubernetes API server.

   The Ignition config files that the installation program generates contain certificates that expire after 24 hours, which are then renewed at that time. If the cluster is shut down before renewing the certificates and the cluster is later restarted after the 24 hours have elapsed, the cluster automatically recovers the expired certificates. The exception is that you must manually approve the pending node-bootstrapper certificate signing requests (CSRs) to recover kubelet certificates. See the documentation for Recovering from expired control plane certificates for more information. It is recommended that you use Ignition config files within 12 hours after they are generated because the 24-hour certificate rotates from 16 to 22 hours after the cluster is installed. By using the Ignition config files within 12 hours, you can avoid installation failure if the certificate update runs during installation.

2. Confirm that the Kubernetes API server is communicating with the pods.

   1. To view a list of all pods, use the following command:

      $ oc get pods --all-namespaces

      Example output

      NAMESPACE                         NAME                                            READY   STATUS      RESTARTS   AGE
      openshift-apiserver-operator      openshift-apiserver-operator-85cb746d55-zqhs8   1/1     Running     1          9m
      openshift-apiserver               apiserver-67b9g                                 1/1     Running     0          3m
      openshift-apiserver               apiserver-ljcmx                                 1/1     Running     0          1m
      openshift-apiserver               apiserver-z25h4                                 1/1     Running     0          2m
      openshift-authentication-operator authentication-operator-69d5d8bf84-vh2n8        1/1     Running     0          5m
      ...

   2. View the logs for a pod that is listed in the output of the previous command by using the following command:

      $ oc logs <pod_name> -n <namespace> (1)

      1	Specify the pod name and namespace, as shown in the output of the previous command.

      If the pod logs display, the Kubernetes API server can communicate with the cluster machines.

3. For an installation with Fibre Channel Protocol (FCP), additional steps are required to enable multipathing. Do not enable multipathing during installation.

   See “Enabling multipathing with kernel arguments on FCOS” in the Post-installation machine configuration tasks documentation for more information.

4. Register your cluster on the Cluster registration page.

You can add extra compute machines after the cluster installation is completed by following Adding compute machines to vSphere.

Backing up VMware vSphere volumes

OKD provisions new volumes as independent persistent disks to freely attach and detach the volume on any node in the cluster. As a consequence, it is not possible to back up volumes that use snapshots, or to restore volumes from snapshots. See Snapshot Limitations for more information.

Procedure

To create a backup of persistent volumes:

1. Stop the application that is using the persistent volume.

2. Clone the persistent volume.

3. Restart the application.

4. Create a backup of the cloned volume.

5. Delete the cloned volume.

Additional resources

• See About remote health monitoring for more information about the Telemetry service

Next steps

• Customize your cluster.

• Configure image streams for the Cluster Samples Operator and the must-gather tool.

• Learn how to use Operator Lifecycle Manager (OLM) on restricted networks.

• If the mirror registry that you used to install your cluster has a trusted CA, add it to the cluster by configuring additional trust stores.

• If necessary, you can opt out of remote health reporting.

• Optional: View the events from the vSphere Problem Detector Operator to determine if the cluster has permission or storage configuration issues.