Overview

OpenShift Container Platform can be configured to access an Azure infrastructure, including using Azure disk as persistent storage for application data. After Azure is configured properly, some additional configurations need to be completed on the OpenShift Container Platform hosts.

Permissions

Configuring Azure for OpenShift Container Platform requires the following role:

Contributor

To create and manage all types of Azure resources.

The Azure Configuration File

Configuring OpenShift Container Platform for Azure requires the /etc/azure/azure.conf file, on each node host.

If the file does not exist, create it, and add the following:

tenantId: <> (1)
subscriptionId: <> (2)
aadClientId: <> (3)
aadClientSecret: <> (4)
aadTenantId: <> (5)
resourceGroup: <> (6)
cloud: <> (7)
location: <> (8)
vnetName: <> (9)
securityGroupName: <> (10)
primaryAvailabilitySetName: <> (11)
1 The AAD tenant ID for the subscription that the cluster is deployed in.
2 The Azure subscription ID that the cluster is deployed in.
3 The client ID for an AAD application with RBAC access to talk to Azure RM APIs.
4 The client secret for an AAD application with RBAC access to talk to Azure RM APIs.
5 Ensure this is the same as tenant ID (optional).
6 The Azure Resource Group name that the Azure VM belongs to.
7 The specific cloud region. For example, AzurePublicCloud.
8 The compact style Azure region. For example, southeastasia (optional).
9 Virtual network containing instances and used when creating load balancers.
10 Security group name associated with instances and load balancers.
11 Availability set to use when creating resources such as load balancers (optional).

The NIC used for accessing the instance must have an internal-dns-name set or the node will not be able to rejoin the cluster, display build logs to the console, and will cause oc rsh to not work correctly.

Configuring Masters

Edit or create the master configuration file on all masters (/etc/origin/master/master-config.yaml by default) and update the contents of the apiServerArguments and controllerArguments sections:

kubernetesMasterConfig:
  ...
  apiServerArguments:
    cloud-provider:
      - "azure"
    cloud-config:
      - "/etc/azure/azure.conf"
  controllerArguments:
    cloud-provider:
      - "azure"
    cloud-config:
      - "/etc/azure/azure.conf"

When triggering a containerized installation, only the /etc/origin and /var/lib/origin directories are mounted to the master and node container. Therefore, master-config.yaml should be in /etc/origin/master instead of /etc/.

Configuring Nodes

  1. Edit or create the node configuration file on all nodes (/etc/origin/node/node-config.yaml by default) and update the contents of the kubeletArguments section:

    kubeletArguments:
      cloud-provider:
        - "azure"
      cloud-config:
        - "/etc/azure/azure.conf"

    When triggering a containerized installation, only the /etc/origin and /var/lib/origin directories are mounted to the master and node container. Therefore, node-config.yaml should be in /etc/origin/node instead of /etc/.

Applying Configuration Changes

Start or restart OpenShift Container Platform services on all master and node hosts to apply your configuration changes, see Restarting OpenShift Container Platform services:

# systemctl restart atomic-openshift-master-api atomic-openshift-master-controllers
# systemctl restart atomic-openshift-node

Switching from not using a cloud provider to using a cloud provider produces an error message. Adding the cloud provider tries to delete the node because the node switches from using the hostname as the externalID (which would have been the case when no cloud provider was being used) to using the cloud provider’s instance-id (which is what the cloud provider specifies). To resolve this issue:

  1. Log in to the CLI as a cluster administrator.

  2. Check and back up existing node labels:

    $ oc describe node <node_name> | grep -Poz '(?s)Labels.*\n.*(?=Taints)'
  3. Delete the nodes:

    $ oc delete node <node_name>
  4. On each node host, restart the OpenShift Container Platform service.

    # systemctl restart atomic-openshift-node
  5. Add back any labels on each node that you previously had.