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Configuring an Azure account - Installing on Azure | Installing | OpenShift Container Platform 4.15
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Before you can install OpenShift Container Platform, you must configure a Microsoft Azure account to meet installation requirements.

All Azure resources that are available through public endpoints are subject to resource name restrictions, and you cannot create resources that use certain terms. For a list of terms that Azure restricts, see Resolve reserved resource name errors in the Azure documentation.

Azure account limits

The OpenShift Container Platform cluster uses a number of Microsoft Azure components, and the default Azure subscription and service limits, quotas, and constraints affect your ability to install OpenShift Container Platform clusters.

Default limits vary by offer category types, such as Free Trial and Pay-As-You-Go, and by series, such as Dv2, F, and G. For example, the default for Enterprise Agreement subscriptions is 350 cores.

Check the limits for your subscription type and if necessary, increase quota limits for your account before you install a default cluster on Azure.

The following table summarizes the Azure components whose limits can impact your ability to install and run OpenShift Container Platform clusters.

Component Number of components required by default Default Azure limit Description

vCPU

44

20 per region

A default cluster requires 44 vCPUs, so you must increase the account limit.

By default, each cluster creates the following instances:

  • One bootstrap machine, which is removed after installation

  • Three control plane machines

  • Three compute machines

Because the bootstrap and control plane machines use Standard_D8s_v3 virtual machines, which use 8 vCPUs, and the compute machines use Standard_D4s_v3 virtual machines, which use 4 vCPUs, a default cluster requires 44 vCPUs. The bootstrap node VM, which uses 8 vCPUs, is used only during installation.

To deploy more worker nodes, enable autoscaling, deploy large workloads, or use a different instance type, you must further increase the vCPU limit for your account to ensure that your cluster can deploy the machines that you require.

OS Disk

7

Each cluster machine must have a minimum of 100 GB of storage and 300 IOPS. While these are the minimum supported values, faster storage is recommended for production clusters and clusters with intensive workloads. For more information about optimizing storage for performance, see the page titled "Optimizing storage" in the "Scalability and performance" section.

VNet

1

1000 per region

Each default cluster requires one Virtual Network (VNet), which contains two subnets.

Network interfaces

7

65,536 per region

Each default cluster requires seven network interfaces. If you create more machines or your deployed workloads create load balancers, your cluster uses more network interfaces.

Network security groups

2

5000

Each cluster creates network security groups for each subnet in the VNet. The default cluster creates network security groups for the control plane and for the compute node subnets:

controlplane

Allows the control plane machines to be reached on port 6443 from anywhere

node

Allows worker nodes to be reached from the internet on ports 80 and 443

Network load balancers

3

1000 per region

Each cluster creates the following load balancers:

default

Public IP address that load balances requests to ports 80 and 443 across worker machines

internal

Private IP address that load balances requests to ports 6443 and 22623 across control plane machines

external

Public IP address that load balances requests to port 6443 across control plane machines

If your applications create more Kubernetes LoadBalancer service objects, your cluster uses more load balancers.

Public IP addresses

3

Each of the two public load balancers uses a public IP address. The bootstrap machine also uses a public IP address so that you can SSH into the machine to troubleshoot issues during installation. The IP address for the bootstrap node is used only during installation.

Private IP addresses

7

The internal load balancer, each of the three control plane machines, and each of the three worker machines each use a private IP address.

Spot VM vCPUs (optional)

0

If you configure spot VMs, your cluster must have two spot VM vCPUs for every compute node.

20 per region

This is an optional component. To use spot VMs, you must increase the Azure default limit to at least twice the number of compute nodes in your cluster.

Using spot VMs for control plane nodes is not recommended.

Additional resources

Configuring a public DNS zone in Azure

To install OpenShift Container Platform, the Microsoft Azure account you use must have a dedicated public hosted DNS zone in your account. This zone must be authoritative for the domain. This service provides cluster DNS resolution and name lookup for external connections to the cluster.

Procedure
  1. Identify your domain, or subdomain, and registrar. You can transfer an existing domain and registrar or obtain a new one through Azure or another source.

    For more information about purchasing domains through Azure, see Buy a custom domain name for Azure App Service in the Azure documentation.

  2. If you are using an existing domain and registrar, migrate its DNS to Azure. See Migrate an active DNS name to Azure App Service in the Azure documentation.

  3. Configure DNS for your domain. Follow the steps in the Tutorial: Host your domain in Azure DNS in the Azure documentation to create a public hosted zone for your domain or subdomain, extract the new authoritative name servers, and update the registrar records for the name servers that your domain uses.

    Use an appropriate root domain, such as openshiftcorp.com, or subdomain, such as clusters.openshiftcorp.com.

  4. If you use a subdomain, follow your company’s procedures to add its delegation records to the parent domain.

Increasing Azure account limits

To increase an account limit, file a support request on the Azure portal.

You can increase only one type of quota per support request.

Procedure
  1. From the Azure portal, click Help + support in the lower left corner.

  2. Click New support request and then select the required values:

    1. From the Issue type list, select Service and subscription limits (quotas).

    2. From the Subscription list, select the subscription to modify.

    3. From the Quota type list, select the quota to increase. For example, select Compute-VM (cores-vCPUs) subscription limit increases to increase the number of vCPUs, which is required to install a cluster.

    4. Click Next: Solutions.

  3. On the Problem Details page, provide the required information for your quota increase:

    1. Click Provide details and provide the required details in the Quota details window.

    2. In the SUPPORT METHOD and CONTACT INFO sections, provide the issue severity and your contact details.

  4. Click Next: Review + create and then click Create.

Recording the subscription and tenant IDs

The installation program requires the subscription and tenant IDs that are associated with your Azure account. You can use the Azure CLI to gather this information.

Prerequisites
  • You have installed or updated the Azure CLI.

Procedure
  1. Log in to the Azure CLI by running the following command:

    $ az login
  2. Ensure that you are using the right subscription:

    1. View a list of available subscriptions by running the following command:

      $ az account list --refresh
      Example output
      [
        {
          "cloudName": "AzureCloud",
          "id": "8xxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx",
          "isDefault": true,
          "name": "Subscription Name 1",
          "state": "Enabled",
          "tenantId": "6xxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx",
          "user": {
            "name": "you@example.com",
            "type": "user"
          }
        },
        {
          "cloudName": "AzureCloud",
          "id": "9xxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx",
          "isDefault": false,
          "name": "Subscription Name 2",
          "state": "Enabled",
          "tenantId": "7xxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx",
          "user": {
            "name": "you2@example.com",
            "type": "user"
          }
        }
      ]
    2. View the details of the active account, and confirm that this is the subscription you want to use, by running the following command:

      $ az account show
      Example output
      {
        "environmentName": "AzureCloud",
        "id": "8xxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx",
        "isDefault": true,
        "name": "Subscription Name 1",
        "state": "Enabled",
        "tenantId": "6xxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx",
        "user": {
          "name": "you@example.com",
          "type": "user"
        }
      }
  3. If you are not using the right subscription:

    1. Change the active subscription by running the following command:

      $ az account set -s <subscription_id>
    2. Verify that you are using the subscription you need by running the following command:

      $ az account show
      Example output
      {
        "environmentName": "AzureCloud",
        "id": "9xxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx",
        "isDefault": true,
        "name": "Subscription Name 2",
        "state": "Enabled",
        "tenantId": "7xxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx",
        "user": {
          "name": "you2@example.com",
          "type": "user"
        }
      }
  4. Record the id and tenantId parameter values from the output. You require these values to install an OpenShift Container Platform cluster.

Supported identities to access Azure resources

An OpenShift Container Platform cluster requires an Azure identity to create and manage Azure resources. As such, you need one of the following types of identities to complete the installation:

  • A service principal

  • A system-assigned managed identity

  • A user-assigned managed identity

Required Azure roles

An OpenShift Container Platform cluster requires an Azure identity to create and manage Azure resources. Before you create the identity, verify that your environment meets the following requirements:

  • The Azure account that you use to create the identity is assigned the User Access Administrator and Contributor roles. These roles are required when:

    • Creating a service principal or user-assigned managed identity.

    • Enabling a system-assigned managed identity on a virtual machine.

  • If you are going to use a service principal to complete the installation, verify that the Azure account that you use to create the identity is assigned the microsoft.directory/servicePrincipals/createAsOwner permission in Microsoft Entra ID.

To set roles on the Azure portal, see the Manage access to Azure resources using RBAC and the Azure portal in the Azure documentation.

Required Azure permissions for installer-provisioned infrastructure

The installation program requires access to an Azure service principal or managed identity with the necessary permissions to deploy the cluster and to maintain its daily operation. These permissions must be granted to the Azure subscription that is associated with the identity.

The following options are available to you:

  • You can assign the identity the Contributor and User Access Administrator roles. Assigning these roles is the quickest way to grant all of the required permissions.

    For more information about assigning roles, see the Azure documentation for managing access to Azure resources using the Azure portal.

  • If your organization’s security policies require a more restrictive set of permissions, you can create a custom role with the necessary permissions.

The following permissions are required for creating an OpenShift Container Platform cluster on Microsoft Azure.

Required permissions for creating authorization resources
  • Microsoft.Authorization/policies/audit/action

  • Microsoft.Authorization/policies/auditIfNotExists/action

  • Microsoft.Authorization/roleAssignments/read

  • Microsoft.Authorization/roleAssignments/write

Required permissions for creating compute resources
  • Microsoft.Compute/availabilitySets/read

  • Microsoft.Compute/availabilitySets/write

  • Microsoft.Compute/disks/beginGetAccess/action

  • Microsoft.Compute/disks/delete

  • Microsoft.Compute/disks/read

  • Microsoft.Compute/disks/write

  • Microsoft.Compute/galleries/images/read

  • Microsoft.Compute/galleries/images/versions/read

  • Microsoft.Compute/galleries/images/versions/write

  • Microsoft.Compute/galleries/images/write

  • Microsoft.Compute/galleries/read

  • Microsoft.Compute/galleries/write

  • Microsoft.Compute/snapshots/read

  • Microsoft.Compute/snapshots/write

  • Microsoft.Compute/snapshots/delete

  • Microsoft.Compute/virtualMachines/delete

  • Microsoft.Compute/virtualMachines/powerOff/action

  • Microsoft.Compute/virtualMachines/read

  • Microsoft.Compute/virtualMachines/write

Required permissions for creating identity management resources
  • Microsoft.ManagedIdentity/userAssignedIdentities/assign/action

  • Microsoft.ManagedIdentity/userAssignedIdentities/read

  • Microsoft.ManagedIdentity/userAssignedIdentities/write

Required permissions for creating network resources
  • Microsoft.Network/dnsZones/A/write

  • Microsoft.Network/dnsZones/CNAME/write

  • Microsoft.Network/dnszones/CNAME/read

  • Microsoft.Network/dnszones/read

  • Microsoft.Network/loadBalancers/backendAddressPools/join/action

  • Microsoft.Network/loadBalancers/backendAddressPools/read

  • Microsoft.Network/loadBalancers/backendAddressPools/write

  • Microsoft.Network/loadBalancers/read

  • Microsoft.Network/loadBalancers/write

  • Microsoft.Network/networkInterfaces/delete

  • Microsoft.Network/networkInterfaces/join/action

  • Microsoft.Network/networkInterfaces/read

  • Microsoft.Network/networkInterfaces/write

  • Microsoft.Network/networkSecurityGroups/join/action

  • Microsoft.Network/networkSecurityGroups/read

  • Microsoft.Network/networkSecurityGroups/securityRules/delete

  • Microsoft.Network/networkSecurityGroups/securityRules/read

  • Microsoft.Network/networkSecurityGroups/securityRules/write

  • Microsoft.Network/networkSecurityGroups/write

  • Microsoft.Network/privateDnsZones/A/read

  • Microsoft.Network/privateDnsZones/A/write

  • Microsoft.Network/privateDnsZones/A/delete

  • Microsoft.Network/privateDnsZones/SOA/read

  • Microsoft.Network/privateDnsZones/read

  • Microsoft.Network/privateDnsZones/virtualNetworkLinks/read

  • Microsoft.Network/privateDnsZones/virtualNetworkLinks/write

  • Microsoft.Network/privateDnsZones/write

  • Microsoft.Network/publicIPAddresses/delete

  • Microsoft.Network/publicIPAddresses/join/action

  • Microsoft.Network/publicIPAddresses/read

  • Microsoft.Network/publicIPAddresses/write

  • Microsoft.Network/virtualNetworks/join/action

  • Microsoft.Network/virtualNetworks/read

  • Microsoft.Network/virtualNetworks/subnets/join/action

  • Microsoft.Network/virtualNetworks/subnets/read

  • Microsoft.Network/virtualNetworks/subnets/write

  • Microsoft.Network/virtualNetworks/write

The following permissions are not required to create the private OpenShift Container Platform cluster on Azure.

  • Microsoft.Network/dnsZones/A/write

  • Microsoft.Network/dnsZones/CNAME/write

  • Microsoft.Network/dnszones/CNAME/read

  • Microsoft.Network/dnszones/read

Required permissions for checking the health of resources
  • Microsoft.Resourcehealth/healthevent/Activated/action

  • Microsoft.Resourcehealth/healthevent/InProgress/action

  • Microsoft.Resourcehealth/healthevent/Pending/action

  • Microsoft.Resourcehealth/healthevent/Resolved/action

  • Microsoft.Resourcehealth/healthevent/Updated/action

Required permissions for creating a resource group
  • Microsoft.Resources/subscriptions/resourceGroups/read

  • Microsoft.Resources/subscriptions/resourcegroups/write

Required permissions for creating resource tags
  • Microsoft.Resources/tags/write

Required permissions for creating storage resources
  • Microsoft.Storage/storageAccounts/blobServices/read

  • Microsoft.Storage/storageAccounts/blobServices/containers/write

  • Microsoft.Storage/storageAccounts/fileServices/read

  • Microsoft.Storage/storageAccounts/fileServices/shares/read

  • Microsoft.Storage/storageAccounts/fileServices/shares/write

  • Microsoft.Storage/storageAccounts/fileServices/shares/delete

  • Microsoft.Storage/storageAccounts/listKeys/action

  • Microsoft.Storage/storageAccounts/read

  • Microsoft.Storage/storageAccounts/write

Optional permissions for creating a private storage endpoint for the image registry
  • Microsoft.Network/privateEndpoints/write

  • Microsoft.Network/privateEndpoints/read

  • Microsoft.Network/privateEndpoints/privateDnsZoneGroups/write

  • Microsoft.Network/privateEndpoints/privateDnsZoneGroups/read

  • Microsoft.Network/privateDnsZones/join/action

  • Microsoft.Storage/storageAccounts/PrivateEndpointConnectionsApproval/action

Optional permissions for creating marketplace virtual machine resources
  • Microsoft.MarketplaceOrdering/offertypes/publishers/offers/plans/agreements/read

  • Microsoft.MarketplaceOrdering/offertypes/publishers/offers/plans/agreements/write

Optional permissions for creating compute resources
  • Microsoft.Compute/availabilitySets/delete

  • Microsoft.Compute/images/read

  • Microsoft.Compute/images/write

  • Microsoft.Compute/images/delete

Optional permissions for enabling user-managed encryption
  • Microsoft.Compute/diskEncryptionSets/read

  • Microsoft.Compute/diskEncryptionSets/write

  • Microsoft.Compute/diskEncryptionSets/delete

  • Microsoft.KeyVault/vaults/read

  • Microsoft.KeyVault/vaults/write

  • Microsoft.KeyVault/vaults/delete

  • Microsoft.KeyVault/vaults/deploy/action

  • Microsoft.KeyVault/vaults/keys/read

  • Microsoft.KeyVault/vaults/keys/write

  • Microsoft.Features/providers/features/register/action

Optional permissions for installing a cluster using the NatGateway outbound type
  • Microsoft.Network/natGateways/read

  • Microsoft.Network/natGateways/write

Optional permissions for installing a private cluster with Azure Network Address Translation (NAT)
  • Microsoft.Network/natGateways/join/action

  • Microsoft.Network/natGateways/read

  • Microsoft.Network/natGateways/write

Optional permissions for installing a private cluster with Azure firewall
  • Microsoft.Network/azureFirewalls/applicationRuleCollections/write

  • Microsoft.Network/azureFirewalls/read

  • Microsoft.Network/azureFirewalls/write

  • Microsoft.Network/routeTables/join/action

  • Microsoft.Network/routeTables/read

  • Microsoft.Network/routeTables/routes/read

  • Microsoft.Network/routeTables/routes/write

  • Microsoft.Network/routeTables/write

  • Microsoft.Network/virtualNetworks/peer/action

  • Microsoft.Network/virtualNetworks/virtualNetworkPeerings/read

  • Microsoft.Network/virtualNetworks/virtualNetworkPeerings/write

Optional permission for running gather bootstrap
  • Microsoft.Compute/virtualMachines/retrieveBootDiagnosticsData/action

The following permissions are required for deleting an OpenShift Container Platform cluster on Microsoft Azure. You can use the same permissions to delete a private OpenShift Container Platform cluster on Azure.

Required permissions for deleting authorization resources
  • Microsoft.Authorization/roleAssignments/delete

Required permissions for deleting compute resources
  • Microsoft.Compute/disks/delete

  • Microsoft.Compute/galleries/delete

  • Microsoft.Compute/galleries/images/delete

  • Microsoft.Compute/galleries/images/versions/delete

  • Microsoft.Compute/virtualMachines/delete

Required permissions for deleting identity management resources
  • Microsoft.ManagedIdentity/userAssignedIdentities/delete

Required permissions for deleting network resources
  • Microsoft.Network/dnszones/read

  • Microsoft.Network/dnsZones/A/read

  • Microsoft.Network/dnsZones/A/delete

  • Microsoft.Network/dnsZones/CNAME/read

  • Microsoft.Network/dnsZones/CNAME/delete

  • Microsoft.Network/loadBalancers/delete

  • Microsoft.Network/networkInterfaces/delete

  • Microsoft.Network/networkSecurityGroups/delete

  • Microsoft.Network/privateDnsZones/read

  • Microsoft.Network/privateDnsZones/A/read

  • Microsoft.Network/privateDnsZones/delete

  • Microsoft.Network/privateDnsZones/virtualNetworkLinks/delete

  • Microsoft.Network/publicIPAddresses/delete

  • Microsoft.Network/virtualNetworks/delete

The following permissions are not required to delete a private OpenShift Container Platform cluster on Azure.

  • Microsoft.Network/dnszones/read

  • Microsoft.Network/dnsZones/A/read

  • Microsoft.Network/dnsZones/A/delete

  • Microsoft.Network/dnsZones/CNAME/read

  • Microsoft.Network/dnsZones/CNAME/delete

Required permissions for checking the health of resources
  • Microsoft.Resourcehealth/healthevent/Activated/action

  • Microsoft.Resourcehealth/healthevent/Resolved/action

  • Microsoft.Resourcehealth/healthevent/Updated/action

Required permissions for deleting a resource group
  • Microsoft.Resources/subscriptions/resourcegroups/delete

Required permissions for deleting storage resources
  • Microsoft.Storage/storageAccounts/delete

  • Microsoft.Storage/storageAccounts/listKeys/action

To install OpenShift Container Platform on Azure, you must scope the permissions to your subscription. Later, you can re-scope these permissions to the installer created resource group. If the public DNS zone is present in a different resource group, then the network DNS zone related permissions must always be applied to your subscription. By default, the OpenShift Container Platform installation program assigns the Azure identity the Contributor role.

You can scope all the permissions to your subscription when deleting an OpenShift Container Platform cluster.

Using Azure managed identities

The installation program requires an Azure identity to complete the installation. You can use either a system-assigned or user-assigned managed identity.

If you are unable to use a managed identity, you can use a service principal.

Procedure
  1. If you are using a system-assigned managed identity, enable it on the virtual machine that you will run the installation program from.

  2. If you are using a user-assigned managed identity:

    1. Assign it to the virtual machine that you will run the installation program from.

    2. Record its client ID. You require this value when installing the cluster.

      For more information about viewing the details of a user-assigned managed identity, see the Microsoft Azure documentation for listing user-assigned managed identities.

  3. Verify that the required permissions are assigned to the managed identity.

Creating a service principal

The installation program requires an Azure identity to complete the installation. You can use a service principal.

If you are unable to use a service principal, you can use a managed identity.

Prerequisites
  • You have installed or updated the Azure CLI.

  • You have an Azure subscription ID.

  • If you are not going to assign the Contributor and User Administrator Access roles to the service principal, you have created a custom role with the required Azure permissions.

Procedure
  1. Create the service principal for your account by running the following command:

    $ az ad sp create-for-rbac --role <role_name> \(1)
         --name <service_principal> \(2)
         --scopes /subscriptions/<subscription_id> (3)
    1 Defines the role name. You can use the Contributor role, or you can specify a custom role which contains the necessary permissions.
    2 Defines the service principal name.
    3 Specifies the subscription ID.
    Example output
    Creating 'Contributor' role assignment under scope '/subscriptions/<subscription_id>'
    The output includes credentials that you must protect. Be sure that you do not
    include these credentials in your code or check the credentials into your source
    control. For more information, see https://aka.ms/azadsp-cli
    {
      "appId": "axxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx",
      "displayName": <service_principal>",
      "password": "00000000-0000-0000-0000-000000000000",
      "tenantId": "8xxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx"
    }
  2. Record the values of the appId and password parameters from the output. You require these values when installing the cluster.

  3. If you applied the Contributor role to your service principal, assign the User Administrator Access role by running the following command:

    $ az role assignment create --role "User Access Administrator" \
      --assignee-object-id $(az ad sp show --id <appId> --query id -o tsv) (1)
      --scope /subscriptions/<subscription_id> (2)
    
    1 Specify the appId parameter value for your service principal.
    2 Specifies the subscription ID.

Supported Azure Marketplace regions

Installing a cluster using the Azure Marketplace image is available to customers who purchase the offer in North America and EMEA.

While the offer must be purchased in North America or EMEA, you can deploy the cluster to any of the Azure public partitions that OpenShift Container Platform supports.

Deploying a cluster using the Azure Marketplace image is not supported for the Azure Government regions.

Supported Azure regions

The installation program dynamically generates the list of available Microsoft Azure regions based on your subscription.

Supported Azure public regions

  • australiacentral (Australia Central)

  • australiaeast (Australia East)

  • australiasoutheast (Australia South East)

  • brazilsouth (Brazil South)

  • canadacentral (Canada Central)

  • canadaeast (Canada East)

  • centralindia (Central India)

  • centralus (Central US)

  • eastasia (East Asia)

  • eastus (East US)

  • eastus2 (East US 2)

  • francecentral (France Central)

  • germanywestcentral (Germany West Central)

  • israelcentral (Israel Central)

  • italynorth (Italy North)

  • japaneast (Japan East)

  • japanwest (Japan West)

  • koreacentral (Korea Central)

  • koreasouth (Korea South)

  • mexicocentral (Mexico Central)

  • northcentralus (North Central US)

  • northeurope (North Europe)

  • norwayeast (Norway East)

  • polandcentral (Poland Central)

  • qatarcentral (Qatar Central)

  • southafricanorth (South Africa North)

  • southcentralus (South Central US)

  • southeastasia (Southeast Asia)

  • southindia (South India)

  • spaincentral (Spain Central)

  • swedencentral (Sweden Central)

  • switzerlandnorth (Switzerland North)

  • uaenorth (UAE North)

  • uksouth (UK South)

  • ukwest (UK West)

  • westcentralus (West Central US)

  • westeurope (West Europe)

  • westindia (West India)

  • westus (West US)

  • westus2 (West US 2)

  • westus3 (West US 3)

Supported Azure Government regions

Support for the following Microsoft Azure Government (MAG) regions was added in OpenShift Container Platform version 4.6:

  • usgovtexas (US Gov Texas)

  • usgovvirginia (US Gov Virginia)

You can reference all available MAG regions in the Azure documentation. Other provided MAG regions are expected to work with OpenShift Container Platform, but have not been tested.

Next steps