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Installing a cluster on OpenStack with Kuryr

Prerequisites

  • Review details about the OpenShift Container Platform installation and update processes.

  • Verify that your network configuration does not rely on a provider network. Provider networks are not supported.

  • Have a storage service installed in RHOSP, like block storage (Cinder) or object storage (Swift). Object storage is the recommended storage technology for OpenShift Container Platform registry cluster deployment. For more information, see Optimizing storage.

About Kuryr SDN

Kuryr is a container network interface (CNI) plug-in solution that uses the Neutron and Octavia Red Hat OpenStack Platform (RHOSP) services to provide networking for pods and Services.

Kuryr and OpenShift Container Platform integration is primarily designed for OpenShift Container Platform clusters running on RHOSP VMs. Kuryr improves the network performance by plugging OpenShift Container Platform pods into RHOSP SDN. In addition, it provides interconnectivity between pods and RHOSP virtual instances.

Kuryr components are installed as pods in OpenShift Container Platform using the openshift-kuryr namespace:

  • kuryr-controller - a single service instance installed on a master node. This is modeled in OpenShift Container Platform as a Deployment object.

  • kuryr-cni - a container installing and configuring Kuryr as a CNI driver on each OpenShift Container Platform node. This is modeled in OpenShift Container Platform as a DaemonSet object.

The Kuryr controller watches the OpenShift Container Platform API server for pod, service, and namespace create, update, and delete events. It maps the OpenShift Container Platform API calls to corresponding objects in Neutron and Octavia. This means that every network solution that implements the Neutron trunk port functionality can be used to back OpenShift Container Platform via Kuryr. This includes open source solutions such as Open vSwitch (OVS) and Open Virtual Network (OVN) as well as Neutron-compatible commercial SDNs.

Kuryr is recommended for OpenShift Container Platform deployments on encapsulated RHOSP tenant networks to avoid double encapsulation, such as running an encapsulated OpenShift Container Platform SDN over an RHOSP network.

If you use provider networks or tenant VLANs, you do not need to use Kuryr to avoid double encapsulation. The performance benefit is negligible. Depending on your configuration, though, using Kuryr to avoid having two overlays might still be beneficial.

Kuryr is not recommended in deployments where all of the following criteria are true:

  • The RHOSP version is less than 16.

  • The deployment uses UDP services, or a large number of TCP services on few hypervisors.

or

  • The ovn-octavia Octavia driver is disabled.

  • The deployment uses a large number of TCP services on few hypervisors.

Resource guidelines for installing OpenShift Container Platform on RHOSP with Kuryr

When using Kuryr SDN, the pods, services, namespaces, and network policies are using resources from the RHOSP quota; this increases the minimum requirements. Kuryr also has some additional requirements on top of what a default install requires.

Use the following quota to satisfy a default cluster’s minimum requirements:

Table 1. Recommended resources for a default OpenShift Container Platform cluster on RHOSP with Kuryr
Resource Value

Floating IP addresses

3 - plus the expected number of Services of LoadBalancer type

Ports

1500 - 1 needed per Pod

Routers

1

Subnets

250 - 1 needed per Namespace/Project

Networks

250 - 1 needed per Namespace/Project

RAM

112 GB

vCPUs

28

Volume storage

275 GB

Instances

7

Security groups

250 - 1 needed per Service and per NetworkPolicy

Security group rules

1000

Load balancers

100 - 1 needed per Service

Load balancer listeners

500 - 1 needed per Service-exposed port

Load balancer pools

500 - 1 needed per Service-exposed port

A cluster might function with fewer than recommended resources, but its performance is not guaranteed.

If RHOSP object storage (Swift) is available and operated by a user account with the swiftoperator role, it is used as the default backend for the OpenShift Container Platform image registry. In this case, the volume storage requirement is 175 GB. Swift space requirements vary depending on the size of the image registry.

If you are using Red Hat OpenStack Platform (RHOSP) version 16 with the Amphora driver rather than the OVN Octavia driver, security groups are associated with service accounts instead of user projects.

Take the following notes into consideration when setting resources:

  • The number of ports that are required is larger than the number of pods. Kuryr uses ports pools to have pre-created ports ready to be used by pods and speed up the pods' booting time.

  • each network policy is mapped into an RHOSP security group, and depending on the NetworkPolicy spec, one or more rules are added to the security group.

  • each service is mapped to an RHOSP load balancer. Consider this requirement when estimating the number of security groups required for the quota.

    If you are using RHOSP version 15 or earlier, or the ovn-octavia driver, each load balancer has a security group with the user project.

  • The quota does not account for load balancer resources (such as VM resources), but you must consider these resources when you decide the RHOSP deployment’s size. The default installation will have more than 50 load balancers; the clusters must be able to accommodate them.

    If you are using RHOSP version 16 with the OVN Octavia driver enabled, only one load balancer VM is generated; services are load balanced through OVN flows.

An OpenShift Container Platform deployment comprises control plane machines, compute machines, and a bootstrap machine.

To enable Kuryr SDN, your environment must meet the following requirements:

  • Run RHOSP 13+.

  • Have Overcloud with Octavia.

  • Use Neutron Trunk ports extension.

  • Use openvswitch firewall driver if ML2/OVS Neutron driver is used instead of ovs-hybrid.

Increasing quota

When using Kuryr SDN, you must increase quotas to satisfy the Red Hat OpenStack Platform (RHOSP) resources used by pods, services, namespaces, and network policies.

Procedure

  • Increase the quotas for a project by running the following command:

    $ sudo openstack quota set --secgroups 250 --secgroup-rules 1000 --ports 1500 --subnets 250 --networks 250 <project>

Configuring Neutron

Kuryr CNI leverages the Neutron Trunks extension to plug containers into the Red Hat OpenStack Platform (RHOSP) SDN, so you must use the trunks extension for Kuryr to properly work.

In addition, if you leverage the default ML2/OVS Neutron driver, the firewall must be set to openvswitch instead of ovs_hybrid so that security groups are enforced on trunk subports and Kuryr can properly handle network policies.

Configuring Octavia

Kuryr SDN uses Red Hat OpenStack Platform (RHOSP)'s Octavia LBaaS to implement OpenShift Container Platform services. Thus, you must install and configure Octavia components in RHOSP to use Kuryr SDN.

To enable Octavia, you must include the Octavia service during the installation of the RHOSP Overcloud, or upgrade the Octavia service if the Overcloud already exists. The following steps for enabling Octavia apply to both a clean install of the Overcloud or an Overcloud update.

The following steps only capture the key pieces required during the deployment of RHOSP when dealing with Octavia. It is also important to note that registry methods vary.

This example uses the local registry method.
Procedure

  1. If you are using the local registry, create a template to upload the images to the registry. For example:

    (undercloud) $ openstack overcloud container image prepare \
-e /usr/share/openstack-tripleo-heat-templates/environments/services-docker/octavia.yaml \
--namespace=registry.access.redhat.com/rhosp13 \
--push-destination=<local-ip-from-undercloud.conf>:8787 \
--prefix=openstack- \
--tag-from-label {version}-{release} \
--output-env-file=/home/stack/templates/overcloud_images.yaml \
--output-images-file /home/stack/local_registry_images.yaml

  2. Verify that the local_registry_images.yaml file contains the Octavia images. For example:

    ...
- imagename: registry.access.redhat.com/rhosp13/openstack-octavia-api:13.0-43
  push_destination: <local-ip-from-undercloud.conf>:8787
- imagename: registry.access.redhat.com/rhosp13/openstack-octavia-health-manager:13.0-45
  push_destination: <local-ip-from-undercloud.conf>:8787
- imagename: registry.access.redhat.com/rhosp13/openstack-octavia-housekeeping:13.0-45
  push_destination: <local-ip-from-undercloud.conf>:8787
- imagename: registry.access.redhat.com/rhosp13/openstack-octavia-worker:13.0-44
  push_destination: <local-ip-from-undercloud.conf>:8787

    The Octavia container versions vary depending upon the specific RHOSP release installed.

  3. Pull the container images from registry.redhat.io to the Undercloud node:

    (undercloud) $ sudo openstack overcloud container image upload \
  --config-file  /home/stack/local_registry_images.yaml \
  --verbose

    This may take some time depending on the speed of your network and Undercloud disk.

  4. Since an Octavia load balancer is used to access the OpenShift Container Platform API, you must increase their listeners' default timeouts for the connections. The default timeout is 50 seconds. Increase the timeout to 20 minutes by passing the following file to the Overcloud deploy command:

    (undercloud) $ cat octavia_timeouts.yaml
parameter_defaults:
  OctaviaTimeoutClientData: 1200000
  OctaviaTimeoutMemberData: 1200000

    This is not needed for RHOSP 13.0.13+.

  5. Install or update your Overcloud environment with Octavia:

    $ openstack overcloud deploy --templates \
  -e /usr/share/openstack-tripleo-heat-templates/environments/services-docker/octavia.yaml \
  -e octavia_timeouts.yaml

    This command only includes the files associated with Octavia; it varies based on your specific installation of RHOSP. See the RHOSP documentation for further information. For more information on customizing your Octavia installation, see installation of Octavia using Director.

    When leveraging Kuryr SDN, the Overcloud installation requires the Neutron trunk extension. This is available by default on director deployments. Use the openvswitch firewall instead of the default ovs-hybrid when the Neutron backend is ML2/OVS. There is no need for modifications if the backend is ML2/OVN.

  6. In RHOSP versions earlier than 13.0.13, add the project ID to the octavia.conf configuration file after you create the project.

    • To enforce network policies across services, like when traffic goes through the Octavia load balancer, you must ensure Octavia creates the Amphora VM security groups on the user project.

      This change ensures that required load balancer security groups belong to that project, and that they can be updated to enforce services isolation.

      This task is unnecessary in RHOSP version 13.0.13 or later.

      Octavia implements a new ACL API that restricts access to the load balancers VIP.

      1. Get the project ID

        $ openstack project show <project>
        example output
        +-------------+----------------------------------+
| Field       | Value                            |
+-------------+----------------------------------+
| description |                                  |
| domain_id   | default                          |
| enabled     | True                             |
| id          | PROJeCT_ID                       |
| is_domain   | False                            |
| name        | *<project>*                      |
| parent_id   | default                          |
| tags        | []                               |
+-------------+----------------------------------+

      2. Add the project ID to octavia.conf for the controllers.

        1. Source the stackrc file:

          $ source stackrc  # Undercloud credentials

        2. List the Overcloud controllers:

          $ openstack server list
          example output
          +--------------------------------------+--------------+--------+-----------------------+----------------+------------+
│
| ID                                   | Name         | Status | Networks
| Image          | Flavor     |
│
+--------------------------------------+--------------+--------+-----------------------+----------------+------------+
│
| 6bef8e73-2ba5-4860-a0b1-3937f8ca7e01 | controller-0 | ACTIVe |
ctlplane=192.168.24.8 | overcloud-full | controller |
│
| dda3173a-ab26-47f8-a2dc-8473b4a67ab9 | compute-0    | ACTIVe |
ctlplane=192.168.24.6 | overcloud-full | compute    |
│
+--------------------------------------+--------------+--------+-----------------------+----------------+------------+

        3. SSH into the controller(s).

          $ ssh heat-admin@192.168.24.8

        4. edit the octavia.conf file to add the project into the list of projects where Amphora security groups are on the user’s account.

          # List of project IDs that are allowed to have Load balancer security groups
# belonging to them.
amp_secgroup_allowed_projects = PROJeCT_ID

      3. Restart the Octavia worker so the new configuration loads.

        controller-0$ sudo docker restart octavia_worker

Depending on your RHOSP environment, Octavia might not support UDP listeners. If you use Kuryr SDN on RHOSP version 13.0.13 or earlier, UDP services are not supported. RHOSP version 16 or later support UDP.

The Octavia OVN Driver

Octavia supports multiple provider drivers through the Octavia API.

To see all available Octavia provider drivers, on a command line, enter:

$ openstack loadbalancer provider list
example output
+---------+-------------------------------------------------+
| name    | description                                     |
+---------+-------------------------------------------------+
| amphora | The Octavia Amphora driver.                     |
| octavia | Deprecated alias of the Octavia Amphora driver. |
| ovn     | Octavia OVN driver.                             |
+---------+-------------------------------------------------+

Beginning with RHOSP version 16, the Octavia OVN provider driver (ovn) is supported on OpenShift Container Platform on RHOSP deployments.

ovn is an integration driver for the load balancing that Octavia and OVN provide. It supports basic load balancing capabilities, and is based on OpenFlow rules. The driver is automatically enabled in Octavia by Director on deployments that use OVN Neutron ML2.

The Amphora provider driver is the default driver. If ovn is enabled, however, Kuryr uses it.

If Kuryr uses ovn instead of Amphora, it offers the following benefits:

  • Decreased resource requirements. Kuryr does not require a load balancer VM for each service.

  • Reduced network latency.

  • Increased service creation speed by using OpenFlow rules instead of a VM for each service.

  • Distributed load balancing actions across all nodes instead of centralized on Amphora VMs.

You can configure your cluster to use the Octavia OVN driver after your RHOSP cloud is upgraded from version 13 to version 16.

Known limitations of installing with Kuryr

Using OpenShift Container Platform with Kuryr SDN has several known limitations.

RHOSP general limitations

OpenShift Container Platform with Kuryr SDN does not support Service objects with type NodePort.

RHOSP version limitations

Using OpenShift Container Platform with Kuryr SDN has several limitations that depend on the RHOSP version.

  • RHOSP versions before 16 use the default Octavia load balancer driver (Amphora). This driver requires that one Amphora load balancer VM is deployed per OpenShift Container Platform service. Creating too many services can cause you to run out of resources.

    Deployments of later versions of RHOSP that have the OVN Octavia driver disabled also use the Amphora driver. They are subject to the same resource concerns as earlier versions of RHOSP.

  • Octavia RHOSP versions before 13.0.13 do not support UDP listeners. Therefore, OpenShift Container Platform UDP services are not supported.

  • Octavia RHOSP versions before 13.0.13 cannot listen to multiple protocols on the same port. Services that expose the same port to different protocols, like TCP and UDP, are not supported.

RHOSP environment limitations

There are limitations when using Kuryr SDN that depend on your deployment environment.

Because of Octavia’s lack of support for the UDP protocol and multiple listeners, if the RHOSP version is earlier than 13.0.13, Kuryr forces pods to use TCP for DNS resolution.

In Go versions 1.12 and earlier, applications that are compiled with CGO support disabled use UDP only. In this case, the native Go resolver does not recognize the use-vc option in resolv.conf, which controls whether TCP is forced for DNS resolution. As a result, UDP is still used for DNS resolution, which fails.

To ensure that TCP forcing is allowed, compile applications either with the environment variable CGO_eNABLeD set to 1, i.e. CGO_eNABLeD=1, or ensure that the variable is absent.

In Go versions 1.13 and later, TCP is used automatically if DNS resolution using UDP fails.

musl-based containers, including Alpine-based containers, do not support the use-vc option.

RHOSP upgrade limitations

As a result of the RHOSP upgrade process, the Octavia API might be changed, and upgrades to the Amphora images that are used for load balancers might be required.

You can address API changes on an individual basis.

If the Amphora image is upgraded, the RHOSP operator can handle existing load balancer VMs in two ways:

  • Upgrade each VM by triggering a load balancer failover.

  • Leave responsibility for upgrading the VMs to users.

If the operator takes the first option, there might be short downtimes during failovers.

If the operator takes the second option, the existing load balancers will not support upgraded Octavia API features, like UDP listeners. In this case, users must recreate their Services to use these features.

If OpenShift Container Platform detects a new Octavia version that supports UDP load balancing, it recreates the DNS service automatically. The service recreation ensures that the service default supports UDP load balancing.

The recreation causes the DNS service approximately one minute of downtime.

Control plane and compute machines

By default, the OpenShift Container Platform installation process stands up three control plane and three compute machines.

each machine requires:

  • An instance from the RHOSP quota

  • A port from the RHOSP quota

  • A flavor with at least 16 GB memory, 4 vCPUs, and 25 GB storage space

Compute machines host the applications that you run on OpenShift Container Platform; aim to run as many as you can.

Bootstrap machine

During installation, a bootstrap machine is temporarily provisioned to stand up the control plane. After the production control plane is ready, the bootstrap machine is deprovisioned.

The bootstrap machine requires:

  • An instance from the RHOSP quota

  • A port from the RHOSP quota

  • A flavor with at least 16 GB memory, 4 vCPUs, and 25 GB storage space

Internet and Telemetry access for OpenShift Container Platform

In OpenShift Container Platform 4.5, you require access to the Internet to install your cluster. The Telemetry service, which runs by default to provide metrics about cluster health and the success of updates, also requires Internet access. If your cluster is connected to the Internet, Telemetry runs automatically, and your cluster is registered to the Red Hat OpenShift Cluster Manager (OCM).

Once you confirm that your Red Hat OpenShift Cluster Manager inventory is correct, either maintained automatically by Telemetry or manually using OCM, use subscription watch to track your OpenShift Container Platform subscriptions at the account or multi-cluster level.

You must have Internet access to:

  • Access the Red Hat OpenShift Cluster Manager page to download the installation program and perform subscription management. If the cluster has Internet access and you do not disable Telemetry, that service automatically entitles your cluster.

  • Access Quay.io to obtain the packages that are required to install your cluster.

  • Obtain the packages that are required to perform cluster updates.

If your cluster cannot have direct Internet access, you can perform a restricted network installation on some types of infrastructure that you provision. During that process, you download the content that is required and use it to populate a mirror registry with the packages that you need to install a cluster and generate the installation program. With some installation types, the environment that you install your cluster in will not require Internet access. Before you update the cluster, you update the content of the mirror registry.

enabling Swift on RHOSP

Swift is operated by a user account with the swiftoperator role. Add the role to an account before you run the installation program.

If the Red Hat OpenStack Platform (RHOSP) object storage service, commonly known as Swift, is available, OpenShift Container Platform uses it as the image registry storage. If it is unavailable, the installation program relies on the RHOSP block storage service, commonly known as Cinder.

If Swift is present and you want to use it, you must enable access to it. If it is not present, or if you do not want to use it, skip this section.
Prerequisites

  • You have a RHOSP administrator account on the target environment.

  • The Swift service is installed.

  • On Ceph RGW, the account in url option is enabled.

Procedure

To enable Swift on RHOSP:

  1. As an administrator in the RHOSP CLI, add the swiftoperator role to the account that will access Swift:

    $ openstack role add --user <user> --project <project> swiftoperator

Your RHOSP deployment can now use Swift for the image registry.

Verifying external network access

The OpenShift Container Platform installation process requires external network access. You must provide an external network value to it, or deployment fails. Before you begin the process, verify that a network with the external router type exists in Red Hat OpenStack Platform (RHOSP).

Prerequisites
Procedure

  1. Using the RHOSP CLI, verify the name and ID of the 'external' network:

    $ openstack network list --long -c ID -c Name -c "Router Type"
    example output
    +--------------------------------------+----------------+-------------+
| ID                                   | Name           | Router Type |
+--------------------------------------+----------------+-------------+
| 148a8023-62a7-4672-b018-003462f8d7dc | public_network | external    |
+--------------------------------------+----------------+-------------+

A network with an external router type appears in the network list. If at least one does not, see Creating a default floating IP network and Creating a default provider network.

If the external network’s CIDR range overlaps one of the default network ranges, you must change the matching network ranges in the install-config.yaml file before you start the installation process.

The default network ranges are:

Network Range

machineNetwork

10.0.0.0/16

serviceNetwork

172.30.0.0/16

clusterNetwork

10.128.0.0/14
If the installation program finds multiple networks with the same name, it sets one of them at random. To avoid this behavior, create unique names for resources in RHOSP.

If the Neutron trunk service plug-in is enabled, a trunk port is created by default. For more information, see Neutron trunk port.

Defining parameters for the installation program

The OpenShift Container Platform installation program relies on a file that is called clouds.yaml. The file describes Red Hat OpenStack Platform (RHOSP) configuration parameters, including the project name, log in information, and authorization service URLs.

Procedure

  1. Create the clouds.yaml file:

    • If your RHOSP distribution includes the Horizon web UI, generate a clouds.yaml file in it.

      Remember to add a password to the auth field. You can also keep secrets in a separate file from clouds.yaml.

    • If your RHOSP distribution does not include the Horizon web UI, or you do not want to use Horizon, create the file yourself. For detailed information about clouds.yaml, see Config files in the RHOSP documentation.

      clouds:
  shiftstack:
    auth:
      auth_url: http://10.10.14.42:5000/v3
      project_name: shiftstack
      username: shiftstack_user
      password: XXX
      user_domain_name: Default
      project_domain_name: Default
  dev-env:
    region_name: RegionOne
    auth:
      username: 'devuser'
      password: XXX
      project_name: 'devonly'
      auth_url: 'https://10.10.14.22:5001/v2.0'

  2. If your RHOSP installation uses self-signed certificate authority (CA) certificates for endpoint authentication:

    1. Copy the certificate authority file to your machine.

    2. Add the machine to the certificate authority trust bundle:

      $ sudo cp ca.crt.pem /etc/pki/ca-trust/source/anchors/

    3. Update the trust bundle:

      $ sudo update-ca-trust extract

    4. Add the cacerts key to the clouds.yaml file. The value must be an absolute, non-root-accessible path to the CA certificate:

      clouds:
  shiftstack:
    ...
    cacert: "/etc/pki/ca-trust/source/anchors/ca.crt.pem"

      After you run the installer with a custom CA certificate, you can update the certificate by editing the value of the ca-cert.pem key in the cloud-provider-config keymap. On a command line, run:

      $ oc edit configmap -n openshift-config cloud-provider-config

  3. Place the clouds.yaml file in one of the following locations:

    1. The value of the OS_CLIeNT_CONFIG_FILe environment variable

    2. The current directory

    3. A Unix-specific user configuration directory, for example ~/.config/openstack/clouds.yaml

    4. A Unix-specific site configuration directory, for example /etc/openstack/clouds.yaml

      The installation program searches for clouds.yaml in that order.

Obtaining the installation program

Before you install OpenShift Container Platform, download the installation file on a local computer.

Prerequisites

  • You must install the cluster from a computer that uses Linux or macOS.

  • You need 500 MB of local disk space to download the installation program.

Procedure

  1. Access the Infrastructure Provider page on the Red Hat OpenShift Cluster Manager site. If you have a Red Hat account, log in with your credentials. If you do not, create an account.

  2. Navigate to the page for your installation type, download the installation program for your operating system, and place the file in the directory where you will store the installation configuration files.

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

    Deleting the files created by the installation program does not remove your cluster, even if the cluster failed during installation. You must complete the OpenShift Container Platform uninstallation procedures outlined for your specific cloud provider to remove your cluster entirely.

  3. extract the installation program. For example, on a computer that uses a Linux operating system, run the following command:

    $ tar xvf <installation_program>.tar.gz

  4. From the Pull Secret page on the Red Hat OpenShift Cluster Manager site, download your installation pull secret as a .txt file. 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 OpenShift Container Platform components.

Creating the installation configuration file

You can customize the OpenShift Container Platform cluster you install on Red Hat OpenStack Platform (RHOSP).

Prerequisites

  • Obtain the OpenShift Container Platform installation program and the pull secret for your cluster.

Procedure

  1. Create the install-config.yaml file.

    1. Run the following command:

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

      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 OpenShift Container Platform version.

    2. At the prompts, provide the configuration details for your cloud:

      1. Optional: Select an SSH key to use to access your cluster machines.

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

      2. Select openstack as the platform to target.

      3. Specify the Red Hat OpenStack Platform (RHOSP) external network name to use for installing the cluster.

      4. Specify the floating IP address to use for external access to the OpenShift API.

      5. Specify a RHOSP flavor with at least 16 GB RAM to use for control plane and compute nodes.

      6. Select the base domain to deploy the cluster to. All DNS records will be sub-domains of this base and will also include the cluster name.

      7. enter a name for your cluster. The name must be 14 or fewer characters long.

      8. Paste the pull secret that you obtained from the Pull Secret page on the Red Hat OpenShift Cluster Manager site.

  2. Modify the install-config.yaml file. You can find more information about the available parameters in the Installation configuration parameters section.

  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 installation process. If you want to reuse the file, you must back it up now.

Configuring the cluster-wide proxy during installation

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

Prerequisites

  • An existing install-config.yaml file.

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

    The Proxy object status.noProxy field is populated with the values of the networking.machineNetwork[].cidr, networking.clusterNetwork[].cidr, and networking.serviceNetwork[] fields from your installation configuration.

    For installations on Amazon Web Services (AWS), Google Cloud Platform (GCP), Microsoft Azure, and Red Hat OpenStack Platform (RHOSP), the Proxy object status.noProxy field is also populated with the instance metadata endpoint (169.254.169.254).
Procedure

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

    apiVersion: v1
baseDomain: my.domain.com
proxy:
  httpProxy: http://<username>:<pswd>@<ip>:<port> (1)
  httpsProxy: http://<username>:<pswd>@<ip>:<port> (2)
  noProxy: example.com (3)
additionalTrustBundle: | (4)
    -----BeGIN CeRTIFICATe-----
    <MY_TRUSTeD_CA_CeRT>
    -----eND CeRTIFICATe-----
...
    1 A proxy URL to use for creating HTTP connections outside the cluster. The URL scheme must be http. 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.
    2 A proxy URL to use for creating HTTPS connections outside the cluster. If this field is not specified, then httpProxy is used for both HTTP and HTTPS connections. 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.
    3 A comma-separated list of destination domain names, domains, IP addresses, or other network CIDRs to exclude proxying. Preface a domain with . to match subdomains only. For example, .y.com matches x.y.com, but not y.com. Use * to bypass proxy for all destinations.
    4 If provided, the installation program generates a config map that is named user-ca-bundle in the openshift-config namespace that contains one or more additional CA certificates that are required for proxying HTTPS connections. The Cluster Network Operator then creates a trusted-ca-bundle config map that merges these contents with the Red Hat enterprise Linux CoreOS (RHCOS) trust bundle, and this config map is referenced in the Proxy object’s trustedCA field. The additionalTrustBundle field is required unless the proxy’s identity certificate is signed by an authority from the RHCOS 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 OpenShift Container Platform.

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.

Installation configuration parameters

Before you deploy an OpenShift Container Platform cluster, you provide parameter values to describe your account on the cloud platform that hosts your cluster and optionally customize your cluster’s platform. When you create the install-config.yaml installation configuration file, you provide values for the required parameters through the command line. If you customize your cluster, you can modify the install-config.yaml file to provide more details about the platform.

After installation, you cannot modify these parameters in the install-config.yaml file.

The openshift-install command does not validate field names for parameters. If an incorrect name is specified, the related file or object is not created, and no error is reported. ensure that the field names for any parameters that are specified are correct.

Required configuration parameters

Required installation configuration parameters are described in the following table:

Table 2. Required parameters
Parameter Description Values

apiVersion

The API version for the install-config.yaml content. The current version is v1. The installer may also support older API versions.

String

baseDomain

The base domain of your cloud provider. The base domain is used to create routes to your OpenShift Container Platform cluster components. The full DNS name for your cluster is a combination of the baseDomain and metadata.name parameter values that uses the <metadata.name>.<baseDomain> format.

A fully-qualified domain or subdomain name, such as example.com.

metadata

Kubernetes resource ObjectMeta, from which only the name parameter is consumed.

Object

metadata.name

The name of the cluster. DNS records for the cluster are all subdomains of {{.metadata.name}}.{{.baseDomain}}.

String of lowercase letters, hyphens (-), and periods (.), such as dev. The string must be 14 characters or fewer long.

platform

The configuration for the specific platform upon which to perform the installation: aws, baremetal, azure, openstack, ovirt, vsphere. For additional information about platform.<platform> parameters, consult the following table for your specific platform.

Object

pullSecret

Get a pull secret from https://cloud.redhat.com/openshift/install/pull-secret to authenticate downloading container images for OpenShift Container Platform components from services such as Quay.io.

 
{
   "auths":{
      "cloud.openshift.com":{
         "auth":"b3Blb=",
         "email":"you@example.com"
      },
      "quay.io":{
         "auth":"b3Blb=",
         "email":"you@example.com"
      }
   }
}

Network configuration parameters

You can customize your installation configuration based on the requirements of your existing network infrastructure. For example, you can expand the IP address block for the cluster network or provide different IP address blocks than the defaults.

Only IPv4 addresses are supported.

Table 3. Network parameters
Parameter Description Values

networking

The configuration for the cluster network.

Object

You cannot modify parameters specified by the networking object after installation.

networking.networkType

The cluster network provider Container Network Interface (CNI) plug-in to install.

either OpenShiftSDN or OVNKubernetes. The default value is OpenShiftSDN.

networking.clusterNetwork

The IP address blocks for pods.

The default value is 10.128.0.0/14 with a host prefix of /23.

If you specify multiple IP address blocks, the blocks must not overlap.

An array of objects. For example:

networking:
  clusterNetwork:
  - cidr: 10.128.0.0/14
    hostPrefix: 23

networking.clusterNetwork.cidr

Required if you use networking.clusterNetwork. An IP address block.

An IPv4 network.

An IP address block in Classless Inter-Domain Routing (CIDR) notation. The prefix length for an IPv4 block is between 0 and 32.

networking.clusterNetwork.hostPrefix

The subnet prefix length to assign to each individual node. For example, if hostPrefix is set to 23 then each node is assigned a /23 subnet out of the given cidr. A hostPrefix value of 23 provides 510 (2^(32 - 23) - 2) pod IP addresses.

A subnet prefix.

The default value is 23.

networking.serviceNetwork

The IP address block for services. The default value is 172.30.0.0/16.

The OpenShift SDN and OVN-Kubernetes network providers support only a single IP address block for the service network.

An array with an IP address block in CIDR format. For example:

networking:
  serviceNetwork:
   - 172.30.0.0/16

networking.machineNetwork

The IP address blocks for machines.

If you specify multiple IP address blocks, the blocks must not overlap.

An array of objects. For example:

networking:
  machineNetwork:
  - cidr: 10.0.0.0/16

networking.machineNetwork.cidr

Required if you use networking.machineNetwork. An IP address block. The default value is 10.0.0.0/16 for all platforms other than libvirt. For libvirt, the default value is 192.168.126.0/24.

An IP network block in CIDR notation.

For example, 10.0.0.0/16.

Set the networking.machineNetwork to match the CIDR that the preferred NIC resides in.

Optional configuration parameters

Optional installation configuration parameters are described in the following table:

Table 4. Optional parameters
Parameter Description Values

additionalTrustBundle

A PeM-encoded X.509 certificate bundle that is added to the nodes' trusted certificate store. This trust bundle may also be used when a proxy has been configured.

String

compute

The configuration for the machines that comprise the compute nodes.

Array of machine-pool objects. For details, see the following "Machine-pool" table.

compute.architecture

Determines the instruction set architecture of the machines in the pool. Currently, heteregeneous clusters are not supported, so all pools must specify the same architecture. Valid values are amd64 (the default).

String

compute.hyperthreading

Whether to enable or disable simultaneous multithreading, or hyperthreading, on compute machines. By default, simultaneous multithreading is enabled to increase the performance of your machines' cores.

If you disable simultaneous multithreading, ensure that your capacity planning accounts for the dramatically decreased machine performance.

enabled or Disabled

compute.name

Required if you use compute. The name of the machine pool.

worker

compute.platform

Required if you use compute. Use this parameter to specify the cloud provider to host the worker machines. This parameter value must match the controlPlane.platform parameter value.

aws, azure, gcp, openstack, ovirt, vsphere, or {}

compute.replicas

The number of compute machines, which are also known as worker machines, to provision.

A positive integer greater than or equal to 2. The default value is 3.

controlPlane

The configuration for the machines that comprise the control plane.

Array of MachinePool objects. For details, see the following "Machine-pool" table.

controlPlane.architecture

Determines the instruction set architecture of the machines in the pool. Currently, heterogeneous clusters are not supported, so all pools must specify the same architecture. Valid values are amd64 (the default).

String

controlPlane.hyperthreading

Whether to enable or disable simultaneous multithreading, or hyperthreading, on control plane machines. By default, simultaneous multithreading is enabled to increase the performance of your machines' cores.

If you disable simultaneous multithreading, ensure that your capacity planning accounts for the dramatically decreased machine performance.

enabled or Disabled

controlPlane.name

Required if you use controlPlane. The name of the machine pool.

master

controlPlane.platform

Required if you use controlPlane. Use this parameter to specify the cloud provider that hosts the control plane machines. This parameter value must match the compute.platform parameter value.

aws, azure, gcp, openstack, ovirt, vsphere, or {}

controlPlane.replicas

The number of control plane machines to provision.

The only supported value is 3, which is the default value.

fips

enable or disable FIPS mode. The default is false (disabled). If FIPS mode is enabled, the Red Hat enterprise Linux CoreOS (RHCOS) machines that OpenShift Container Platform runs on bypass the default Kubernetes cryptography suite and use the cryptography modules that are provided with RHCOS instead.

If you are using Azure File storage, you cannot enable FIPS mode.

false or true

imageContentSources

Sources and repositories for the release-image content.

Array of objects. Includes a source and, optionally, mirrors, as described in the following rows of this table.

imageContentSources.source

Required if you use imageContentSources. Specify the repository that users refer to, for example, in image pull specifications.

String

imageContentSources.mirrors

Specify one or more repositories that may also contain the same images.

Array of strings

publish

How to publish or expose the user-facing endpoints of your cluster, such as the Kubernetes API, OpenShift routes.

Internal or external. The default value is external.

Setting this field to Internal is not supported on non-cloud platforms.

If the value of the field is set to Internal, the cluster will become non-functional. For more information, refer to BZ#1953035.

sshKey

The SSH key to authenticate access to your cluster machines.

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

For example, sshKey: ssh-ed25519 AAAA...

Additional Red Hat OpenStack Platform (RHOSP) configuration parameters

Additional RHOSP configuration parameters are described in the following table:

Table 5. Additional RHOSP parameters
Parameter Description Values

compute.platform.openstack.rootVolume.size

For compute machines, the size in gigabytes of the root volume. If you do not set this value, machines use ephemeral storage.

Integer, for example 30.

compute.platform.openstack.rootVolume.type

For compute machines, the root volume’s type.

String, for example performance.

controlPlane.platform.openstack.rootVolume.size

For control plane machines, the size in gigabytes of the root volume. If you do not set this value, machines use ephemeral storage.

Integer, for example 30.

controlPlane.platform.openstack.rootVolume.type

For control plane machines, the root volume’s type.

String, for example performance.

platform.openstack.cloud

The name of the RHOSP cloud to use from the list of clouds in the clouds.yaml file.

String, for example MyCloud.

platform.openstack.externalNetwork

The RHOSP external network name to be used for installation.

String, for example external.

platform.openstack.computeFlavor

The RHOSP flavor to use for control plane and compute machines.

String, for example m1.xlarge.

platform.openstack.lbFloatingIP

An existing floating IP address to associate with the load balancer API.

An IP address, for example 128.0.0.1.

Optional RHOSP configuration parameters

Optional RHOSP configuration parameters are described in the following table:

Table 6. Optional RHOSP parameters
Parameter Description Values

compute.platform.openstack.additionalNetworkIDs

Additional networks that are associated with compute machines. Allowed address pairs are not created for additional networks.

A list of one or more UUIDs as strings. For example, fa806b2f-ac49-4bce-b9db-124bc64209bf.

compute.platform.openstack.additionalSecurityGroupIDs

Additional security groups that are associated with compute machines.

A list of one or more UUIDs as strings. For example, 7ee219f3-d2e9-48a1-96c2-e7429f1b0da7.

controlPlane.platform.openstack.additionalNetworkIDs

Additional networks that are associated with control plane machines. Allowed address pairs are not created for additional networks.

A list of one or more UUIDs as strings. For example, fa806b2f-ac49-4bce-b9db-124bc64209bf.

controlPlane.platform.openstack.additionalSecurityGroupIDs

Additional security groups that are associated with control plane machines.

A list of one or more UUIDs as strings. For example, 7ee219f3-d2e9-48a1-96c2-e7429f1b0da7.

platform.openstack.clusterOSImage

The location from which the installer downloads the RHCOS image.

You must set this parameter to perform an installation in a restricted network.

An HTTP or HTTPS URL, optionally with an SHA-256 checksum.

For example, http://mirror.example.com/images/rhcos-43.81.201912131630.0-openstack.x86_64.qcow2.gz?sha256=ffebbd68e8a1f2a245ca19522c16c86f67f9ac8e4e0c1f0a812b068b16f7265d.

The value can also be the name of an existing Glance image, for example my-rhcos.

platform.openstack.defaultMachinePlatform

The default machine pool platform configuration.

 
{
   "type": "ml.large",
   "rootVolume": {
      "size": 30,
      "type": "performance"
   }
}

platform.openstack.externalDNS

IP addresses for external DNS servers that cluster instances use for DNS resolution.

A list of IP addresses as strings. For example, ["8.8.8.8", "192.168.1.12"].

platform.openstack.machinesSubnet

The UUID of a RHOSP subnet that the cluster’s nodes use. Nodes and virtual IP (VIP) ports are created on this subnet.

The first item in networking.machineNetwork must match the value of machinesSubnet.

If you deploy to a custom subnet, you cannot specify an external DNS server to the OpenShift Container Platform installer. Instead, add DNS to the subnet in RHOSP.

A UUID as a string, for example fa806b2f-ac49-4bce-b9db-124bc64209bf.

Custom subnets in RHOSP deployments

Optionally, you can deploy a cluster on a Red Hat OpenStack Platform (RHOSP) subnet of your choice. The subnet’s GUID is passed as the value of platform.openstack.machinesSubnet in the install-config.yaml file.

This subnet is used as the cluster’s primary subnet; nodes and ports are created on it.

Before you run the OpenShift Container Platform installer with a custom subnet, verify that:

  • The target network and subnet are available.

  • DHCP is enabled on the target subnet.

  • You can provide installer credentials that have permission to create ports on the target network.

  • If your network configuration requires a router, it is created in RHOSP. Some configurations rely on routers for floating IP address translation.

  • Your network configuration does not rely on a provider network. Provider networks are not supported.

By default, the API VIP takes x.x.x.5 and the Ingress VIP takes x.x.x.7 from your network’s CIDR block. To override these default values, set values for platform.openstack.apiVIP and platform.openstack.ingressVIP that are outside of the DHCP allocation pool.

Sample customized install-config.yaml file for RHOSP with Kuryr

To deploy with Kuryr SDN instead of the default OpenShift SDN, you must modify the install-config.yaml file to include Kuryr as the desired networking.networkType and proceed with the default OpenShift Container Platform SDN installation steps. This sample install-config.yaml demonstrates all of the possible Red Hat OpenStack Platform (RHOSP) customization options.

This sample file is provided for reference only. You must obtain your install-config.yaml file by using the installation program.

 
apiVersion: v1
baseDomain: example.com
clusterID: os-test
controlPlane:
  name: master
  platform: {}
  replicas: 3
compute:
- name: worker
  platform:
    openstack:
      type: ml.large
  replicas: 3
metadata:
  name: example
networking:
  clusterNetwork:
  - cidr: 10.128.0.0/14
    hostPrefix: 23
  machineNetwork:
  - cidr: 10.0.0.0/16
  serviceNetwork:
  - 172.30.0.0/16 (1)
  networkType: Kuryr
platform:
  openstack:
    cloud: mycloud
    externalNetwork: external
    computeFlavor: m1.xlarge
    lbFloatingIP: 128.0.0.1
    trunkSupport: true (2)
    octaviaSupport: true (2)
pullSecret: '{"auths": ...}'
sshKey: ssh-ed25519 AAAA...
1 The Amphora Octavia driver creates two ports per load balancer. As a result, the service subnet that the installer creates is twice the size of the CIDR that is specified as the value of the serviceNetwork property. The larger range is required to prevent IP address conflicts.
2 Both trunkSupport and octaviaSupport are automatically discovered by the installer, so there is no need to set them. But if your environment does not meet both requirements, Kuryr SDN will not properly work. Trunks are needed to connect the pods to the RHOSP network and Octavia is required to create the OpenShift Container Platform services.

Generating an SSH private key and adding it to the agent

If you want to perform installation debugging or disaster recovery on your cluster, you must provide an SSH key to both your ssh-agent and the installation program. You can use this key to access the bootstrap machine in a public cluster to troubleshoot installation issues.

In a production environment, you require disaster recovery and debugging.

You can use this key to SSH into the master nodes as the user core. When you deploy the cluster, the key is added to the core user’s ~/.ssh/authorized_keys list.

Procedure

  1. If you do not have an SSH key that is configured for password-less authentication on your computer, create one. For example, on a computer that uses a Linux operating system, run the following command:

    $ ssh-keygen -t ed25519 -N '' \
    -f <path>/<file_name> (1)
    1 Specify the path and file name, such as ~/.ssh/id_rsa, of the new SSH key. If you have an existing key pair, ensure your public key is in the your ~/.ssh directory.

    Running this command generates an SSH key that does not require a password in the location that you specified.

    If you plan to install an OpenShift Container Platform 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. Start the ssh-agent process as a background task:

    $ eval "$(ssh-agent -s)"
    example output
    Agent pid 31874

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

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

    $ ssh-add <path>/<file_name> (1)
    example output
    Identity added: /home/<you>/<path>/<file_name> (<computer_name>)
    1 Specify the path and file name for your SSH private key, such as ~/.ssh/id_rsa
Next steps

  • When you install OpenShift Container Platform, provide the SSH public key to the installation program.

enabling access to the environment

At deployment, all OpenShift Container Platform machines are created in a Red Hat OpenStack Platform (RHOSP)-tenant network. Therefore, they are not accessible directly in most RHOSP deployments.

You can configure the OpenShift Container Platform API and applications that run on the cluster to be accessible with or without floating IP addresses.

enabling access with floating IP addresses

Create two floating IP (FIP) addresses: one for external access to the OpenShift Container Platform API, the API FIP, and one for OpenShift Container Platform applications, the apps FIP.

The API FIP is also used in the install-config.yaml file.
Procedure

  1. Using the Red Hat OpenStack Platform (RHOSP) CLI, create the API FIP:

    $ openstack floating ip create --description "API <cluster_name>.<base_domain>" <external network>

  2. Using the Red Hat OpenStack Platform (RHOSP) CLI, create the apps, or Ingress, FIP:

    $ openstack floating ip create --description "Ingress <cluster_name>.<base_domain>" <external network>

  3. To reflect the new FIPs, add records that follow these patterns to your DNS server:

    api.<cluster_name>.<base_domain>.  IN  A  <API_FIP>
*.apps.<cluster_name>.<base_domain>. IN  A <apps_FIP>

    If you do not control the DNS server you can add the record to your /etc/hosts file instead. This action makes the API accessible to you only, which is not suitable for production deployment but does allow installation for development and testing.

You can make OpenShift Container Platform resources available outside of the cluster by assigning a floating IP address and updating your firewall configuration.

enabling access without floating IP addresses

If you cannot use floating IP addresses, the OpenShift Container Platform installation might still finish. However, the installation program fails after it times out waiting for API access.

After the installation program times out, the cluster might still initialize. After the bootstrapping processing begins, it must complete. You must edit the cluster’s networking configuration after it is deployed.

Deploying the cluster

You can install OpenShift Container Platform on a compatible cloud platform.

You can run the create cluster command of the installation program only once, during initial installation.
Prerequisites

  • Obtain the OpenShift Container Platform installation program and the pull secret for your cluster.

Procedure

  1. Run the installation program:

    $ ./openshift-install create cluster --dir=<installation_directory> \ (1)
    --log-level=info (2)
    1 For <installation_directory>, specify the location of your customized ./install-config.yaml file.
    2 To view different installation details, specify warn, debug, or error instead of info.

    If the cloud provider account that you configured on your host does not have sufficient permissions to deploy the cluster, the installation process stops, and the missing permissions are displayed.

    When the cluster deployment completes, directions for accessing your cluster, including a link to its web console and credentials for the kubeadmin user, display in your terminal.

    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.

    You must not delete the installation program or the files that the installation program creates. Both are required to delete the cluster.

Verifying cluster status

You can verify your OpenShift Container Platform cluster’s status during or after installation.

Procedure

  1. In the cluster environment, export the administrator’s kubeconfig file:

    $ export KUBeCONFIG=<installation_directory>/auth/kubeconfig (1)
    1 For <installation_directory>, specify the path to the directory that you stored the installation files in.

    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.

  2. View the control plane and compute machines created after a deployment:

    $ oc get nodes

  3. View your cluster’s version:

    $ oc get clusterversion

  4. View your Operators' status:

    $ oc get clusteroperator

  5. View all running pods in the cluster:

    $ oc get pods -A

Logging in to the cluster

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 OpenShift Container Platform installation.

Prerequisites

  • Deploy an OpenShift Container Platform cluster.

  • Install the oc CLI.

Procedure

  1. export the kubeadmin credentials:

    $ export KUBeCONFIG=<installation_directory>/auth/kubeconfig (1)
    1 For <installation_directory>, specify the path to the directory that you stored the installation files in.

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

    $ oc whoami
    example output
    system:admin

Configuring application access with floating IP addresses

After you install OpenShift Container Platform, configure Red Hat OpenStack Platform (RHOSP) to allow application network traffic.

Prerequisites

  • OpenShift Container Platform cluster must be installed

  • Floating IP addresses are enabled as described in enabling access to the environment.

Procedure

After you install the OpenShift Container Platform cluster, attach a floating IP address to the ingress port:

  1. Show the port:

    $ openstack port show <cluster name>-<clusterID>-ingress-port

  2. Attach the port to the IP address:

    $ openstack floating ip set --port <ingress port ID> <apps FIP>

  3. Add a wildcard A record for *apps. to your DNS file:

    *.apps.<cluster name>.<base domain>  IN  A  <apps FIP>

If you do not control the DNS server but want to enable application access for non-production purposes, you can add these hostnames to /etc/hosts:

<apps FIP> console-openshift-console.apps.<cluster name>.<base domain>
<apps FIP> integrated-oauth-server-openshift-authentication.apps.<cluster name>.<base domain>
<apps FIP> oauth-openshift.apps.<cluster name>.<base domain>
<apps FIP> prometheus-k8s-openshift-monitoring.apps.<cluster name>.<base domain>
<apps FIP> grafana-openshift-monitoring.apps.<cluster name>.<base domain>
<apps FIP> <app name>.apps.<cluster name>.<base domain>

Next steps