Installing a cluster on VMC with user-provisioned infrastructure and network customizations

    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.

    By customizing your network configuration, your cluster can coexist with existing IP address allocations in your environment and integrate with existing VXLAN configurations. You must set most of the network configuration parameters during installation, and you can modify only kubeProxy configuration parameters in a running cluster.

    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 OKD compute network and the internet. This is used by nodes and applications to download container images.

      • 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

    • 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

    You cannot use the VMware NSX Container Plugin for Kubernetes (NCP), and NSX is not used as the OpenShift SDN. The version of NSX currently available with VMC is incompatible with the version of NCP certified with OKD.

    However, the NSX DHCP service is used for virtual machine IP management with the full-stack automated OKD deployment and with nodes provisioned, either manually or automatically, by the Machine API integration with vSphere. Additionally, NSX firewall rules are created to enable access with the OKD cluster and between the bastion host and the VMC vSphere hosts.

    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

    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.

    Table 1. Minimum supported vSphere version for VMware components
    ComponentMinimum supported versionsDescription

    Hypervisor

    vSphere 6.5 and later with HW version 13

    This version is the minimum version that Fedora CoreOS (FCOS) supports. See the Red Hat Enterprise Linux 8 supported hypervisors list.

    Storage with in-tree drivers

    vSphere 6.5 and later

    This plug-in creates vSphere storage by using the in-tree storage drivers for vSphere included in OKD.

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

    You must ensure that the time on your ESXi hosts is synchronized before you install OKD. See in the VMware documentation.

    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

    The smallest OKD clusters require the following hosts:

    Table 2. Minimum required hosts
    HostsDescription

    One temporary bootstrap machine

    The cluster requires the bootstrap machine to deploy the OKD cluster on the three control plane machines. You can remove the bootstrap machine after you install the cluster.

    Three control plane machines

    The control plane machines run the Kubernetes and OKD services that form the control plane.

    At least two compute machines, which are also known as worker machines.

    The workloads requested by OKD users run on the compute machines.

    To maintain high availability of your cluster, use separate physical hosts for these cluster machines.

    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) or Fedora 7.9.

    See Red Hat Enterprise Linux technology capabilities and limits.

    Minimum resource requirements

    Each cluster machine must meet the following minimum requirements:

    MachineOperating SystemvCPU [1]Virtual RAMStorageIOPS [2]

    Bootstrap

    FCOS

    4

    16 GB

    100 GB

    300

    Control plane

    FCOS

    4

    16 GB

    100 GB

    300

    Compute

    FCOS

    2

    8 GB

    100 GB

    300

    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 7 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.

    Managing certificate signing requests

    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.

    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.

    If a DHCP service is not available for your user-provisioned infrastructure, you can instead 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 Creating Red Hat Enterprise Linux CoreOS (RHCOS) machines section for more information about static IP provisioning and advanced networking options.

    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.

    In connected OKD environments, all nodes are required to have internet access to pull images for platform containers and provide telemetry data to Red Hat.

    Table 3. Ports used for all-machine to all-machine communications
    ProtocolPortDescription

    ICMP

    N/A

    Network reachability tests

    TCP

    1936

    Metrics

    9000-9999

    Host level services, including the node exporter on ports 9100-9101 and the Cluster Version Operator on port 9099.

    10250-10259

    The default ports that Kubernetes reserves

    10256

    openshift-sdn

    UDP

    4789

    VXLAN and Geneve

    6081

    VXLAN and Geneve

    9000-9999

    Host level services, including the node exporter on ports 9100-9101.

    TCP/UDP

    30000-32767

    Kubernetes node port

    Table 4. Ports used for all-machine to control plane communications
    ProtocolPortDescription

    TCP

    6443

    Kubernetes API

    Table 5. Ports used for control plane machine to control plane machine communications
    ProtocolPortDescription

    TCP

    2379-2380

    etcd server and peer ports

    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.

    It is recommended to use a DHCP server to provide the hostnames to each cluster node. See the DHCP recommendations for user-provisioned infrastructure section for more information.

    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>..

    Table 6. Required DNS records
    ComponentRecordDescription

    Kubernetes API

    api.<cluster_name>.<base_domain>.

    A DNS A/AAAA or CNAME record, and a DNS PTR record, to identify the API load balancer. These records must be resolvable by both clients external to the cluster and from all the nodes within the cluster.

    api-int.<cluster_name>.<base_domain>.

    A DNS A/AAAA or CNAME record, and a DNS PTR record, to internally identify the API load balancer. These records must be resolvable from all the nodes within the cluster.

    The API server must be able to resolve the worker nodes by the hostnames that are recorded in Kubernetes. If the API server cannot resolve the node names, then proxied API calls can fail, and you cannot retrieve logs from pods.

    Routes

    *.apps.<cluster_name>.<base_domain>.

    A wildcard DNS A/AAAA or CNAME record that refers to the application ingress load balancer. The application ingress load balancer targets the machines that run the Ingress Controller pods. The Ingress Controller pods run on the compute machines by default. These records must be resolvable by both clients external to the cluster and from all the nodes within the cluster.

    For example, console-openshift-console.apps.<cluster_name>.<base_domain> is used as a wildcard route to the OKD console.

    Bootstrap machine

    bootstrap.<cluster_name>.<base_domain>.

    A DNS A/AAAA or CNAME record, and a DNS PTR record, to identify the bootstrap machine. These records must be resolvable by the nodes within the cluster.

    Control plane machines

    <master><n>.<cluster_name>.<base_domain>.

    DNS A/AAAA or CNAME records and DNS PTR records to identify each machine for the control plane nodes (also known as the master nodes). These records must be resolvable by the nodes within the cluster.

    Compute machines

    <worker><n>.<cluster_name>.<base_domain>.

    DNS A/AAAA or CNAME records and DNS PTR records to identify each machine for the worker nodes. These records must be resolvable by the nodes within the cluster.

    In OKD 4.4 and later, you do not need to specify etcd host and SRV records in your DNS configuration.

    You can use the dig command to verify name and reverse name resolution. See the section on Validating DNS resolution for user-provisioned infrastructure for detailed validation steps.

    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

    1Provides name resolution for the Kubernetes API. The record refers to the IP address of the API load balancer.
    2Provides name resolution for the Kubernetes API. The record refers to the IP address of the API load balancer and is used for internal cluster communications.
    3Provides name resolution for the wildcard routes. The record refers to the IP address of the application ingress load balancer. The application ingress load balancer targets the machines that run the Ingress Controller pods. The Ingress Controller pods run on the compute machines by default.

    In the example, 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.

    4Provides name resolution for the bootstrap machine.
    5Provides name resolution for the control plane machines.
    6Provides name resolution for the compute machines.

    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

    1. $TTL 1W
    2. @ IN SOA ns1.example.com. root (
    3. 2019070700 ; serial
    4. 3H ; refresh (3 hours)
    5. 30M ; retry (30 minutes)
    6. 2W ; expiry (2 weeks)
    7. 1W ) ; minimum (1 week)
    8. IN NS ns1.example.com.
    9. ;
    10. 5.1.168.192.in-addr.arpa. IN PTR api.ocp4.example.com. (1)
    11. 5.1.168.192.in-addr.arpa. IN PTR api-int.ocp4.example.com. (2)
    12. ;
    13. 96.1.168.192.in-addr.arpa. IN PTR bootstrap.ocp4.example.com. (3)
    14. ;
    15. 97.1.168.192.in-addr.arpa. IN PTR master0.ocp4.example.com. (4)
    16. 98.1.168.192.in-addr.arpa. IN PTR master1.ocp4.example.com. (4)
    17. 99.1.168.192.in-addr.arpa. IN PTR master2.ocp4.example.com. (4)
    18. ;
    19. 11.1.168.192.in-addr.arpa. IN PTR worker0.ocp4.example.com. (5)
    20. 7.1.168.192.in-addr.arpa. IN PTR worker1.ocp4.example.com. (5)
    21. ;
    22. ;EOF
    1Provides reverse DNS resolution for the Kubernetes API. The PTR record refers to the record name of the API load balancer.
    2Provides reverse DNS resolution for the Kubernetes API. The PTR record refers to the record name of the API load balancer and is used for internal cluster communications.
    3Provides reverse DNS resolution for the bootstrap machine.
    4Provides reverse DNS resolution for the control plane machines.
    5Provides reverse DNS resolution for the compute machines.

    A PTR record is not required for the OKD application wildcard.

    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 7. API load balancer
      PortBack-end machines (pool members)InternalExternalDescription

      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 8. Application ingress load balancer
      PortBack-end machines (pool members)InternalExternalDescription

      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

    If you are deploying a three-node cluster with zero compute nodes, the Ingress Controller pods run on the control plane nodes. In three-node cluster deployments, you must configure your application ingress load balancer to route HTTP and HTTPS traffic to the control plane nodes.

    A working configuration for the Ingress router is required for an OKD cluster. You must configure the Ingress router after the control plane initializes.

    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.

    In the example, 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.

    Sample API and application ingress load balancer configuration

    1. global
    2. log 127.0.0.1 local2
    3. pidfile /var/run/haproxy.pid
    4. maxconn 4000
    5. daemon
    6. defaults
    7. mode http
    8. log global
    9. option dontlognull
    10. option http-server-close
    11. option redispatch
    12. retries 3
    13. timeout http-request 10s
    14. timeout queue 1m
    15. timeout connect 10s
    16. timeout client 1m
    17. timeout server 1m
    18. timeout http-keep-alive 10s
    19. timeout check 10s
    20. maxconn 3000
    21. frontend stats
    22. bind *:1936
    23. mode http
    24. log global
    25. maxconn 10
    26. stats enable
    27. stats hide-version
    28. stats refresh 30s
    29. stats show-node
    30. stats show-desc Stats for ocp4 cluster (1)
    31. stats auth admin:ocp4
    32. stats uri /stats
    33. listen api-server-6443 (2)
    34. bind *:6443
    35. mode tcp
    36. server bootstrap bootstrap.ocp4.example.com:6443 check inter 1s backup (3)
    37. server master0 master0.ocp4.example.com:6443 check inter 1s
    38. server master1 master1.ocp4.example.com:6443 check inter 1s
    39. server master2 master2.ocp4.example.com:6443 check inter 1s
    40. listen machine-config-server-22623 (4)
    41. bind *:22623
    42. mode tcp
    43. server bootstrap bootstrap.ocp4.example.com:22623 check inter 1s backup (3)
    44. server master0 master0.ocp4.example.com:22623 check inter 1s
    45. server master1 master1.ocp4.example.com:22623 check inter 1s
    46. server master2 master2.ocp4.example.com:22623 check inter 1s
    47. listen ingress-router-443 (5)
    48. bind *:443
    49. mode tcp
    50. balance source
    51. server worker0 worker0.ocp4.example.com:443 check inter 1s
    52. server worker1 worker1.ocp4.example.com:443 check inter 1s
    53. listen ingress-router-80 (6)
    54. bind *:80
    55. mode tcp
    56. balance source
    57. server worker0 worker0.ocp4.example.com:80 check inter 1s
    58. server worker1 worker1.ocp4.example.com:80 check inter 1s
    1In the example, the cluster name is ocp4.
    2Port 6443 handles the Kubernetes API traffic and points to the control plane machines.
    3The bootstrap entries must be in place before the OKD cluster installation and they must be removed after the bootstrap process is complete.
    4Port 22623 handles the machine config server traffic and points to the control plane machines.
    5Port 443 handles the HTTPS traffic and points to the machines that run the Ingress Controller pods. The Ingress Controller pods run on the compute machines by default.
    6Port 80 handles the HTTP traffic and points to the machines that run the Ingress Controller pods. The Ingress Controller pods run on the compute machines by default.

    If you are deploying a three-node cluster with zero compute nodes, the Ingress Controller pods run on the control plane nodes. In three-node cluster deployments, you must configure your application ingress load balancer to route HTTP and HTTPS traffic to the control plane nodes.

    If you are using HAProxy as a load balancer, you can check that the haproxy process is listening on ports 6443, 22623, 443, and 80 by running netstat -nltupe on the HAProxy node.

    If you are using HAProxy as a load balancer and SELinux is set to enforcing, you must ensure that the HAProxy service can bind to the configured TCP port by running setsebool -P haproxy_connect_any=1.

    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 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. 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 Creating Red Hat Enterprise Linux CoreOS (RHCOS) machines 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.

    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.

    Some load balancing solutions require the DNS name resolution for the cluster nodes to be in place before the load balancing is initialized.

    Validating DNS resolution for user-provisioned infrastructure

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

    The validation steps detailed in this section must succeed before you install your cluster.

    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:

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

        1. 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:

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

        Example output

        1. 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:

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

        Example output

        1. 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:

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

        Example output

        1. 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:

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

        Example output

        1. 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:

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

        Example output

        1. 5.1.168.192.in-addr.arpa. 0 IN PTR api-int.ocp4.example.com. (1)
        2. 5.1.168.192.in-addr.arpa. 0 IN PTR api.ocp4.example.com. (2)
        1Provides the record name for the Kubernetes internal API.
        2Provides 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:

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

        Example output

        1. 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.

    Do not skip this procedure in production environments, where disaster recovery and debugging is required.

    You must use a local key, not one that you configured with platform-specific approaches such as AWS key pairs.

    On clusters running Fedora CoreOS (FCOS), the SSH keys specified in the Ignition config files are written to the /home/core/.ssh/authorized_keys.d/core file. However, the Machine Config Operator manages SSH keys in the /home/core/.ssh/authorized_keys file and configures sshd to ignore the /home/core/.ssh/authorized_keys.d/core file. As a result, newly provisioned OKD nodes are not accessible using SSH until the Machine Config Operator reconciles the machine configs with the authorized_keys file. After you can access the nodes using SSH, you can delete the /home/core/.ssh/authorized_keys.d/core file.

    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:

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

      1. $ cat <path>/<file_name>.pub

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

      1. $ 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:

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

        Example output

        1. 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:

      1. $ ssh-add <path>/<file_name> (1)
      1Specify the path and file name for your SSH private key, such as ~/.ssh/id_rsa

      Example output

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

    Next steps

    • When you install OKD, provide the SSH public key to the installation program.

    Obtaining the installation program

    Before you install OKD, download the installation file on a local computer.

    Prerequisites

    • You have a computer that runs Linux or macOS, with 500 MB of local disk space

    Procedure

    1. Download installer from https://github.com/openshift/okd/releases

      The installation program creates several files on the computer that you use to install your cluster. You must keep the installation program and the files that the installation program creates after you finish installing the cluster. Both files are required to delete the cluster.

      Deleting the files created by the installation program does not remove your cluster, even if the cluster failed during installation. To remove your cluster, complete the OKD uninstallation procedures for your specific cloud provider.

    2. From the page on the Red Hat OpenShift Cluster Manager site, download your installation pull secret. This pull secret allows you to authenticate with the services that are provided by the included authorities, including Quay.io, which serves the container images for OKD components.

      Using a pull secret from the Red Hat OpenShift Cluster Manager site is not required. You can use a pull secret for another private registry. Or, if you do not need the cluster to pull images from a private registry, you can use {"auths":{"fake":{"auth":"aWQ6cGFzcwo="}}} as the pull secret when prompted during the installation.

      If you do not use the pull secret from the Red Hat OpenShift Cluster Manager site:

      • Red Hat Operators are not available.

      • The Telemetry and Insights operators do not send data to Red Hat.

      • Content from the Red Hat Container Catalog registry, such as image streams and Operators, are not available.

    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.

    Procedure

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

      1. $ 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.

      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.

    1. apiVersion: v1
    2. baseDomain: example.com (1)
    3. compute:
    4. - hyperthreading: Enabled (2) (3)
    5. name: worker
    6. replicas: 0 (4)
    7. controlPlane:
    8. hyperthreading: Enabled (2) (3)
    9. name: master
    10. replicas: 3 (5)
    11. metadata:
    12. name: test (6)
    13. platform:
    14. vsphere:
    15. vcenter: your.vcenter.server (7)
    16. username: username (8)
    17. password: password (9)
    18. datacenter: datacenter (10)
    19. defaultDatastore: datastore (11)
    20. folder: "/<datacenter_name>/vm/<folder_name>/<subfolder_name>" (12)
    21. pullSecret: '{"auths": ...}' (13)
    22. sshKey: 'ssh-ed25519 AAAA...' (14)
    1The base domain of the cluster. All DNS records must be sub-domains of this base and include the cluster name.
    2The controlPlane section is a single mapping, but the compute section is a sequence of mappings. To meet the requirements of the different data structures, the first line of the compute section must begin with a hyphen, -, and the first line of the controlPlane section must not. Although both sections currently define a single machine pool, it is possible that future versions of OKD will support defining multiple compute pools during installation. Only one control plane pool is used.
    3Whether to enable or disable simultaneous multithreading, or hyperthreading. By default, simultaneous multithreading is enabled to increase the performance of your machines’ cores. You can disable it by setting the parameter value to Disabled. If you disable simultaneous multithreading in some cluster machines, you must disable it in all cluster machines.

    If you disable simultaneous multithreading, ensure that your capacity planning accounts for the dramatically decreased machine performance. Your machines must use at least 8 CPUs and 32 GB of RAM if you disable simultaneous multithreading.

    4You must set the value of the replicas parameter to 0. This parameter controls the number of workers that the cluster creates and manages for you, which are functions that the cluster does not perform when you use user-provisioned infrastructure. You must manually deploy worker machines for the cluster to use before you finish installing OKD.
    5The number of control plane machines that you add to the cluster. Because the cluster uses this values as the number of etcd endpoints in the cluster, the value must match the number of control plane machines that you deploy.
    6The cluster name that you specified in your DNS records.
    7The fully-qualified hostname or IP address of the vCenter server.
    8The name of the user for accessing the server. This user must have at least the roles and privileges that are required for static or dynamic persistent volume provisioning in vSphere.
    9The password associated with the vSphere user.
    10The vSphere datacenter.
    11The default vSphere datastore to use.
    12Optional: For installer-provisioned infrastructure, the absolute path of an existing folder where the installation program creates the virtual machines, for example, /<datacenter_name>/vm/<folder_name>/<subfolder_name>. If you do not provide this value, the installation program creates a top-level folder in the datacenter virtual machine folder that is named with the infrastructure ID. If you are providing the infrastructure for the cluster, omit this parameter.
    13The pull secret that you obtained from the page on the Red Hat OpenShift Cluster Manager site. This pull secret allows you to authenticate with the services that are provided by the included authorities, including Quay.io, which serves the container images for OKD components.
    14The public portion of the default SSH key for the core user in Fedora CoreOS (FCOS).

    For production OKD clusters on which you want to perform installation debugging or disaster recovery, specify an SSH key that your ssh-agent process uses.

    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).

    • If your cluster is on AWS, you added the ec2.<region>.amazonaws.com, elasticloadbalancing.<region>.amazonaws.com, and s3.<region>.amazonaws.com endpoints to your VPC endpoint. These endpoints are required to complete requests from the nodes to the AWS EC2 API. Because the proxy works on the container level, not the node level, you must route these requests to the AWS EC2 API through the AWS private network. Adding the public IP address of the EC2 API to your allowlist in your proxy server is not sufficient.

    Procedure

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

      1. apiVersion: v1
      2. baseDomain: my.domain.com
      3. httpProxy: http://<username>:<pswd>@<ip>:<port> (1)
      4. httpsProxy: https://<username>:<pswd>@<ip>:<port> (2)
      5. noProxy: example.com (3)
      6. additionalTrustBundle: | (4)
      7. -----BEGIN CERTIFICATE-----
      8. <MY_TRUSTED_CA_CERT>
      9. -----END CERTIFICATE-----
      10. ...
      1A proxy URL to use for creating HTTP connections outside the cluster. The URL scheme must be http. If you use an MITM transparent proxy network that does not require additional proxy configuration but requires additional CAs, you must not specify an httpProxy value.
      2A proxy URL to use for creating HTTPS connections outside the cluster. If you use an MITM transparent proxy network that does not require additional proxy configuration but requires additional CAs, you must not specify an httpsProxy value.
      3A 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.
      4If 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. If you use an MITM transparent proxy network that does not require additional proxy configuration but requires additional CAs, you must provide the MITM CA certificate.

      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.

    Only the Proxy object named cluster is supported, and no additional proxies can be created.

    Specifying advanced network configuration

    You can use advanced network configuration for your cluster network provider to integrate your cluster into your existing network environment. You can specify advanced network configuration only before you install the cluster.

    Customizing your network configuration by modifying the OKD manifest files created by the installation program is not supported. Applying a manifest file that you create, as in the following procedure, is supported.

    Prerequisites

    • You have created the install-config.yaml file and completed any modifications to it.

    Procedure

    1. Change to the directory that contains the installation program and create the manifests:

      1. $ ./openshift-install create manifests --dir=<installation_directory> (1)
      1<installation_directory> specifies the name of the directory that contains the install-config.yaml file for your cluster.
    2. Create a stub manifest file for the advanced network configuration that is named cluster-network-03-config.yml in the <installation_directory>/manifests/ directory:

      1. apiVersion: operator.openshift.io/v1
      2. kind: Network
      3. metadata:
      4. name: cluster
      5. spec:
    3. Specify the advanced network configuration for your cluster in the cluster-network-03-config.yml file, such as in the following examples:

      Specify a different VXLAN port for the OpenShift SDN network provider

      1. apiVersion: operator.openshift.io/v1
      2. kind: Network
      3. metadata:
      4. name: cluster
      5. spec:
      6. defaultNetwork:
      7. openshiftSDNConfig:
      8. vxlanPort: 4800

      Enable IPsec for the OVN-Kubernetes network provider

    4. Optional: Back up the manifests/cluster-network-03-config.yml file. The installation program consumes the manifests/ directory when you create the Ignition config files.

    5. Remove the Kubernetes manifest files that define the control plane machines and compute machineSets:

      1. $ 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 MachineSet files to create compute machines by using the machine API, but you must update references to them to match your environment.

    Cluster Network Operator configuration

    The configuration for the cluster network is specified as part of the Cluster Network Operator (CNO) configuration and stored in a custom resource (CR) object that is named cluster. The CR specifies the fields for the Network API in the operator.openshift.io API group.

    The CNO configuration inherits the following fields during cluster installation from the Network API in the Network.config.openshift.io API group and these fields cannot be changed:

    clusterNetwork

    IP address pools from which pod IP addresses are allocated.

    serviceNetwork

    IP address pool for services.

    defaultNetwork.type

    Cluster network provider, such as OpenShift SDN or OVN-Kubernetes.

    You can specify the cluster network provider configuration for your cluster by setting the fields for the defaultNetwork object in the CNO object named cluster.

    Cluster Network Operator configuration object

    The fields for the Cluster Network Operator (CNO) are described in the following table:

    Table 9. Cluster Network Operator configuration object
    FieldTypeDescription

    metadata.name

    string

    The name of the CNO object. This name is always cluster.

    spec.clusterNetwork

    array

    A list specifying the blocks of IP addresses from which pod IP addresses are allocated and the subnet prefix length assigned to each individual node in the cluster. For example:

    1. spec:
    2. clusterNetwork:
    3. - cidr: 10.128.0.0/19
    4. hostPrefix: 23
    5. - cidr: 10.128.32.0/19
    6. hostPrefix: 23

    You can customize this field only in the install-config.yaml file before you create the manifests. The value is read-only in the manifest file.

    spec.serviceNetwork

    array

    A block of IP addresses for services. The OpenShift SDN and OVN-Kubernetes Container Network Interface (CNI) network providers support only a single IP address block for the service network. For example:

    1. spec:
    2. serviceNetwork:
    3. - 172.30.0.0/14

    You can customize this field only in the install-config.yaml file before you create the manifests. The value is read-only in the manifest file.

    spec.defaultNetwork

    object

    Configures the Container Network Interface (CNI) cluster network provider for the cluster network.

    spec.kubeProxyConfig

    object

    The fields for this object specify the kube-proxy configuration. If you are using the OVN-Kubernetes cluster network provider, the kube-proxy configuration has no effect.

    defaultNetwork object configuration

    The values for the defaultNetwork object are defined in the following table:

    Table 10. defaultNetwork object
    FieldTypeDescription

    type

    string

    Either OpenShiftSDN or OVNKubernetes. The cluster network provider is selected during installation. This value cannot be changed after cluster installation.

    OKD uses the OVN-Kubernetes Container Network Interface (CNI) cluster network provider by default.

    openshiftSDNConfig

    object

    This object is only valid for the OpenShift SDN cluster network provider.

    ovnKubernetesConfig

    object

    This object is only valid for the OVN-Kubernetes cluster network provider.

    Configuration for the OpenShift SDN CNI cluster network provider

    The following table describes the configuration fields for the OpenShift SDN Container Network Interface (CNI) cluster network provider.

    Table 11. openshiftSDNConfig object
    FieldTypeDescription

    mode

    string

    Configures the network isolation mode for OpenShift SDN. The default value is NetworkPolicy.

    The values Multitenant and Subnet are available for backwards compatibility with OKD 3.x but are not recommended. This value cannot be changed after cluster installation.

    mtu

    integer

    The maximum transmission unit (MTU) for the VXLAN overlay network. This is detected automatically based on the MTU of the primary network interface. You do not normally need to override the detected MTU.

    If the auto-detected value is not what you expect it to be, confirm that the MTU on the primary network interface on your nodes is correct. You cannot use this option to change the MTU value of the primary network interface on the nodes.

    If your cluster requires different MTU values for different nodes, you must set this value to 50 less than the lowest MTU value in your cluster. For example, if some nodes in your cluster have an MTU of 9001, and some have an MTU of 1500, you must set this value to 1450.

    This value cannot be changed after cluster installation.

    vxlanPort

    integer

    The port to use for all VXLAN packets. The default value is 4789. This value cannot be changed after cluster installation.

    If you are running in a virtualized environment with existing nodes that are part of another VXLAN network, then you might be required to change this. For example, when running an OpenShift SDN overlay on top of VMware NSX-T, you must select an alternate port for the VXLAN, because both SDNs use the same default VXLAN port number.

    On Amazon Web Services (AWS), you can select an alternate port for the VXLAN between port 9000 and port 9999.

    Example OpenShift SDN configuration

    1. defaultNetwork:
    2. type: OpenShiftSDN
    3. openshiftSDNConfig:
    4. mode: NetworkPolicy
    5. mtu: 1450
    6. vxlanPort: 4789
    Configuration for the OVN-Kubernetes CNI cluster network provider

    The following table describes the configuration fields for the OVN-Kubernetes CNI cluster network provider.

    Table 13. policyAuditConfig object
    FieldTypeDescription

    rateLimit

    integer

    The maximum number of messages to generate every second per node. The default value is 20 messages per second.

    maxFileSize

    integer

    The maximum size for the audit log in bytes. The default value is 50000000 or 50MB.

    destination

    string

    One of the following additional audit log targets:

      libc

      The libc syslog() function of the journald process on the host.

      udp:<host>:<port>

      A syslog server. Replace <host>:<port> with the host and port of the syslog server.

      unix:<file>

      A Unix Domain Socket file specified by <file>.

      null

      Do not send the audit logs to any additional target.

    syslogFacility

    string

    The syslog facility, such as kern, as defined by RFC5424. The default value is local0.

    Example OVN-Kubernetes configuration

    1. defaultNetwork:
    2. type: OVNKubernetes
    3. ovnKubernetesConfig:
    4. mtu: 1400
    5. genevePort: 6081
    6. ipsecConfig: {}

    kubeProxyConfig object configuration

    The values for the kubeProxyConfig object are defined in the following table:

    Table 14. kubeProxyConfig object
    FieldTypeDescription

    iptablesSyncPeriod

    string

    The refresh period for iptables rules. The default value is 30s. Valid suffixes include s, m, and h and are described in the documentation.

    Because of performance improvements introduced in OKD 4.3 and greater, adjusting the iptablesSyncPeriod parameter is no longer necessary.

    proxyArguments.iptables-min-sync-period

    array

    The minimum duration before refreshing iptables rules. This field ensures that the refresh does not happen too frequently. Valid suffixes include s, m, and h and are described in the Go time package. The default value is:

    1. kubeProxyConfig:
    2. proxyArguments:
    3. iptables-min-sync-period:
    4. - 0s

    Creating the Ignition config files

    Because you must manually start the cluster machines, you must generate the Ignition config files that the cluster needs to make its machines.

    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.

    Prerequisites

    • Obtain the OKD installation program and the pull secret for your cluster. For a restricted network installation, these files are on your mirror host.

    Procedure

    • Obtain the Ignition config files:

      1. $ ./openshift-install create ignition-configs --dir=<installation_directory> (1)
      1For <installation_directory>, specify the directory name to store the files that the installation program creates.

      If you created an install-config.yaml file, specify the directory that contains it. Otherwise, specify an empty 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.

      The following files are generated in the directory:

      1. .
      2. ├── auth
      3. ├── kubeadmin-password
      4. └── kubeconfig
      5. ├── bootstrap.ign
      6. ├── master.ign
      7. ├── metadata.json
      8. └── worker.ign

    Extracting the infrastructure name

    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:

      1. $ jq -r .infraID <installation_directory>/metadata.json (1)
      1For <installation_directory>, specify the path to the directory that you stored the installation files in.

      Example output

      1. openshift-vw9j6 (1)
      1The 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

    • Obtain the Ignition config files for your cluster.

    • Create a vSphere cluster.

    Procedure

    1. Convert the control plane, compute, and bootstrap Ignition config files to Base64 encoding.

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

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

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

    2. Obtain the FCOS images from the page

    3. 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 FolderNew 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.

    4. 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.

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

      1. Right-click the template name and click CloneClone 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.

      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.

        For a bootstrap machine, specify the URL of the bootstrap Ignition config file that you hosted.

      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 OptionsAdvanced.

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

          1. Set your static IP configuration:

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

            Example command

            1. $ 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:

            1. $ 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.

        • 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 Ignition config file for this machine type. Note for the bootstrap node, the Ignition config file must be provided in guestinfo.ignition.config.data in the Configuration Parameters window. This is due to a restriction in the maximum size of data that can be provided in a vApp property.

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

          • disk.EnableUUID: Specify TRUE.

        • Alternatively, prior to powering on the virtual machine, use vApp properties to:

          • Navigate to a virtual machine from the vCenter Server inventory.

          • On the Configure tab, expand Settings and select vApp options.

          • Scroll down and under Properties, apply the configurations that you just edited.

    1. 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.
    2. 9. Complete the configuration and power on the VM.
    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 CloneClone 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.

      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 OptionsAdvanced.

        • 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.

    1. 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.
    2. 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.

    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 that is inserted during the openshift-install preparation phases of an OKD installation.

    Prerequisites

    • If container storage is on the root partition, ensure that this root partition is mounted with the pquota option by including rootflags=pquota in the GRUB command line.

    • If the container storage is on a partition that is mounted by /etc/fstab, ensure that the following mount option is included in the /etc/fstab file:

      1. /dev/sdb1 /var xfs defaults,pquota 0 0
    • If the container storage is on a partition that is mounted by systemd, ensure that the MachineConfig object includes the following mount option as in this example:

      1. spec:
      2. config:
      3. ignition:
      4. version: 3.2.0
      5. storage:
      6. disks:
      7. - device: /dev/sdb
      8. partitions:
      9. - label: var
      10. sizeMiB: 240000
      11. startMiB: 0
      12. filesystems:
      13. - device: /dev/disk/by-partlabel/var
      14. format: xfs
      15. path: /var
      16. systemd:
      17. units:
      18. - contents: |
      19. [Unit]
      20. [Mount]
      21. Where=/var
      22. What=/dev/disk/by-partlabel/var
      23. Options=defaults,pquota
      24. [Install]
      25. WantedBy=local-fs.target
      26. enabled: true
      27. name: var.mount

    Procedure

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

      1. $ 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:

      1. $ openshift-install create manifests --dir $HOME/clusterconfig
      2. ? SSH Public Key ...
      3. $ ls $HOME/clusterconfig/openshift/
      4. 99_kubeadmin-password-secret.yaml
      5. 99_openshift-cluster-api_master-machines-0.yaml
      6. 99_openshift-cluster-api_master-machines-2.yaml
      7. ...
    3. Create a MachineConfig object and add it to a file in the openshift directory. For example, name the file 98-var-partition.yaml, change the disk device name to the name of the storage device on the worker systems, and set the storage size as appropriate. This attaches storage to a separate /var directory.

      1. apiVersion: machineconfiguration.openshift.io/v1
      2. kind: MachineConfig
      3. metadata:
      4. labels:
      5. machineconfiguration.openshift.io/role: worker
      6. name: 98-var-partition
      7. spec:
      8. config:
      9. ignition:
      10. version: 3.2.0
      11. storage:
      12. disks:
      13. - device: /dev/<device_name> (1)
      14. partitions:
      15. - sizeMiB: <partition_size>
      16. startMiB: <partition_start_offset> (2)
      17. label: var
      18. filesystems:
      19. - path: /var
      20. device: /dev/disk/by-partlabel/var
      21. format: xfs
      22. systemd:
      23. units:
      24. - name: var.mount
      25. enabled: true
      26. contents: |
      27. [Unit]
      28. Before=local-fs.target
      29. [Mount]
      30. Where=/var
      31. What=/dev/disk/by-partlabel/var
      32. [Install]
      33. WantedBy=local-fs.target
      1The storage device name of the disk that you want to partition.
      2When 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.
    4. Run openshift-install again to create Ignition configs from a set of files in the manifest and openshift subdirectories:

      1. $ openshift-install create ignition-configs --dir $HOME/clusterconfig
      2. $ ls $HOME/clusterconfig/
      3. 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.

    It is recommended that you use bootupd only on bare metal or virtualized hypervisor installations, such as for protection against the BootHole vulnerability.

    Manual install method

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

    1. Inspect the system status:

      1. # bootupctl status

      Example output

      1. Component EFI
      2. Installed: grub2-efi-x64-1:2.04-31.fc33.x86_64,shim-x64-15-8.x86_64
      3. 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:

      1. # bootupctl adopt-and-update

      Example output

      1. 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:

      1. # bootupctl update

      Example output

      1. 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

    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.

    • Your machines have direct internet access or have an HTTP or HTTPS proxy available.

    Procedure

    1. Monitor the bootstrap process:

      1. $ ./openshift-install --dir=<installation_directory> wait-for bootstrap-complete \ (1)
      2. --log-level=info (2)
      1For <installation_directory>, specify the path to the directory that you stored the installation files in.
      2To view different installation details, specify warn, debug, or error instead of info.

      Example output

      1. INFO Waiting up to 30m0s for the Kubernetes API at https://api.test.example.com:6443...
      2. INFO API v1.21.0 up
      3. INFO Waiting up to 30m0s for bootstrapping to complete...
      4. 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:

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

      1. $ oc whoami

      Example output

      1. 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:

      1. $ oc get nodes

      Example output

      1. NAME STATUS ROLES AGE VERSION
      2. master-0 Ready master 63m v1.21.0
      3. master-1 Ready master 63m v1.21.0
      4. master-2 Ready master 64m v1.21.0

      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:

      1. $ oc get csr

      Example output

      1. NAME AGE REQUESTOR CONDITION
      2. csr-8b2br 15m system:serviceaccount:openshift-machine-config-operator:node-bootstrapper Pending
      3. csr-8vnps 15m system:serviceaccount:openshift-machine-config-operator:node-bootstrapper Pending
      4. ...

      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:

        1. $ 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:

        1. $ 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:

      1. $ oc get csr

      Example output

      1. NAME AGE REQUESTOR CONDITION
      2. csr-bfd72 5m26s system:node:ip-10-0-50-126.us-east-2.compute.internal Pending
      3. csr-c57lv 5m26s system:node:ip-10-0-95-157.us-east-2.compute.internal Pending
      4. ...
    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:

        1. $ 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:

        1. $ 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:

      1. $ oc get nodes

      Example output

      1. NAME STATUS ROLES AGE VERSION
      2. master-0 Ready master 73m v1.21.0
      3. master-1 Ready master 73m v1.21.0
      4. master-2 Ready master 74m v1.21.0
      5. worker-0 Ready worker 11m v1.21.0
      6. worker-1 Ready worker 11m v1.21.0

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

    Additional information

    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:

      1. $ watch -n5 oc get clusteroperators

      Example output

      1. NAME VERSION AVAILABLE PROGRESSING DEGRADED SINCE
      2. authentication 4.8.2 True False False 19m
      3. baremetal 4.8.2 True False False 37m
      4. cloud-credential 4.8.2 True False False 40m
      5. cluster-autoscaler 4.8.2 True False False 37m
      6. config-operator 4.8.2 True False False 38m
      7. console 4.8.2 True False False 26m
      8. csi-snapshot-controller 4.8.2 True False False 37m
      9. dns 4.8.2 True False False 37m
      10. etcd 4.8.2 True False False 36m
      11. image-registry 4.8.2 True False False 31m
      12. ingress 4.8.2 True False False 30m
      13. insights 4.8.2 True False False 31m
      14. kube-apiserver 4.8.2 True False False 26m
      15. kube-controller-manager 4.8.2 True False False 36m
      16. kube-scheduler 4.8.2 True False False 36m
      17. kube-storage-version-migrator 4.8.2 True False False 37m
      18. machine-api 4.8.2 True False False 29m
      19. machine-approver 4.8.2 True False False 37m
      20. machine-config 4.8.2 True False False 36m
      21. marketplace 4.8.2 True False False 37m
      22. monitoring 4.8.2 True False False 29m
      23. network 4.8.2 True False False 38m
      24. node-tuning 4.8.2 True False False 37m
      25. openshift-apiserver 4.8.2 True False False 32m
      26. openshift-controller-manager 4.8.2 True False False 30m
      27. openshift-samples 4.8.2 True False False 32m
      28. operator-lifecycle-manager 4.8.2 True False False 37m
      29. operator-lifecycle-manager-catalog 4.8.2 True False False 37m
      30. operator-lifecycle-manager-packageserver 4.8.2 True False False 32m
      31. service-ca 4.8.2 True False False 38m
      32. storage 4.8.2 True False False 37m
    2. Configure the Operators that are not available.

    Image registry removed during installation

    On platforms that do not provide shareable object storage, the OpenShift Image Registry Operator bootstraps itself as Removed. This allows openshift-installer to complete installations on these platform types.

    After installation, you must edit the Image Registry Operator configuration to switch the managementState from Removed to Managed.

    The Prometheus console provides an ImageRegistryRemoved alert, for example:

    “Image Registry has been removed. ImageStreamTags, BuildConfigs and DeploymentConfigs which reference ImageStreamTags may not work as expected. Please configure storage and update the config to Managed state by editing configs.imageregistry.operator.openshift.io.”

    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 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.

    Block storage volumes are supported but not recommended for use with image registry on production clusters. An installation where the registry is configured on block storage is not highly available because the registry cannot have more than one replica.

    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:

      1. $ 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:

        1. kind: PersistentVolumeClaim
        2. apiVersion: v1
        3. metadata:
        4. name: image-registry-storage (1)
        5. namespace: openshift-image-registry (2)
        6. spec:
        7. accessModes:
        8. - ReadWriteOnce (3)
        9. resources:
        10. requests:
        11. storage: 100Gi (4)
        1A unique name that represents the PersistentVolumeClaim object.
        2The namespace for the PersistentVolumeClaim object, which is openshift-image-registry.
        3The access mode of the persistent volume claim. With ReadWriteOnce, the volume can be mounted with read and write permissions by a single node.
        4The size of the persistent volume claim.
      2. Create the PersistentVolumeClaim object from the file:

        1. $ oc create -f pvc.yaml -n openshift-image-registry
    3. Edit the registry configuration so that it references the correct PVC:

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

      Example output

      1. storage:
      2. pvc:
      3. claim: (1)
      1Creating 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 .

    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:

      1. $ watch -n5 oc get clusteroperators

      Example output

      1. NAME VERSION AVAILABLE PROGRESSING DEGRADED SINCE
      2. authentication 4.8.2 True False False 19m
      3. baremetal 4.8.2 True False False 37m
      4. cloud-credential 4.8.2 True False False 40m
      5. cluster-autoscaler 4.8.2 True False False 37m
      6. config-operator 4.8.2 True False False 38m
      7. console 4.8.2 True False False 26m
      8. csi-snapshot-controller 4.8.2 True False False 37m
      9. dns 4.8.2 True False False 37m
      10. etcd 4.8.2 True False False 36m
      11. image-registry 4.8.2 True False False 31m
      12. ingress 4.8.2 True False False 30m
      13. insights 4.8.2 True False False 31m
      14. kube-apiserver 4.8.2 True False False 26m
      15. kube-controller-manager 4.8.2 True False False 36m
      16. kube-scheduler 4.8.2 True False False 36m
      17. kube-storage-version-migrator 4.8.2 True False False 37m
      18. machine-api 4.8.2 True False False 29m
      19. machine-approver 4.8.2 True False False 37m
      20. machine-config 4.8.2 True False False 36m
      21. marketplace 4.8.2 True False False 37m
      22. monitoring 4.8.2 True False False 29m
      23. network 4.8.2 True False False 38m
      24. node-tuning 4.8.2 True False False 37m
      25. openshift-apiserver 4.8.2 True False False 32m
      26. openshift-controller-manager 4.8.2 True False False 30m
      27. openshift-samples 4.8.2 True False False 32m
      28. operator-lifecycle-manager 4.8.2 True False False 37m
      29. operator-lifecycle-manager-catalog 4.8.2 True False False 37m
      30. operator-lifecycle-manager-packageserver 4.8.2 True False False 32m
      31. service-ca 4.8.2 True False False 38m
      32. storage 4.8.2 True False False 37m

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

      1. $ ./openshift-install --dir=<installation_directory> wait-for install-complete (1)
      1For <installation_directory>, specify the path to the directory that you stored the installation files in.

      Example output

      1. 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.

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

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

        1. $ oc get pods --all-namespaces

        Example output

        1. NAMESPACE NAME READY STATUS RESTARTS AGE
        2. openshift-apiserver-operator openshift-apiserver-operator-85cb746d55-zqhs8 1/1 Running 1 9m
        3. openshift-apiserver apiserver-67b9g 1/1 Running 0 3m
        4. openshift-apiserver apiserver-ljcmx 1/1 Running 0 1m
        5. openshift-apiserver apiserver-z25h4 1/1 Running 0 2m
        6. ...
      2. View the logs for a pod that is listed in the output of the previous command by using the following command:

        1Specify 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.

      When installing with multipath, it is strongly recommended to enable it at installation time, and not at a later time, which can cause problems.

      See “Enabling multipathing with kernel arguments on FCOS” in the Installing on bare metal documentation for more information.

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

    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 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