When Security Policies in your NSX-V environment use only a Network Introspection service that is provided by a partner, two approaches are available to migrate the NSX-V prepared hosts to NSX-T.

Both the approaches discussed in this topic assume that the partner service virtual machines (SVMs) in your NSX-V environment are not deleted before starting the migration coordinator. Depending on how much security protection downtime you are willing to accept during host migration, choose the host migration approach that best suits your needs.

Note: Consult the VMware partner before migrating the hosts by using any of the two approaches. Check with the partner whether their service is supported for migration to NSX-T and seek their inputs before the migration. Partners will have their own guidance to migrate their service to NSX-T.

When only Network Introspection service is running on your NSX-V hosts, In-Place host migration mode is not supported. Only Maintenance migration mode is supported. However, Automated Maintenance migration mode is recommended.

Approach 1: Involves more security protection downtime

This approach is the simpler of the two host migration approaches. However, it involves more security protection downtime compared to Approach 2. Let us say that you have three clusters in your NSX-V environment: Cluster 1, Cluster 2, and Cluster 3.

In this approach, enable the Pause between groups migration setting and migrate Cluster 1 by using the standard host migration procedure that is explained in Migrate NSX-V Hosts. After Cluster 1 is migrated to NSX-T, the migration pauses. Deploy the partner service in Cluster 1 by doing either a host-based or a clustered service deployment. Now, disable the Pause between groups migration setting, and continue migrating Clusters 2 and 3. After the workload VMs in Clusters 2 and 3 are migrated to NSX-T, these workloads can start redirecting packets to the partner service virtual machines (SVM) in Cluster 1.

In this approach, security protection downtime is expected during migration of Cluster 1.

When workload VMs migrate to an NSX-T host, existing data traffic during a host migration is expected to have a security protection downtime. However, new data traffic does not have a security protection downtime.

Approach 2: Involves minimal security protection downtime

This approach requires some manual intervention with an NSX-T API to create a temporary host group. Enable the Pause between groups migration setting and migrate any one host from Cluster 1. After this host in Cluster 1 is migrated to NSX-T, the migration coordinator pauses. Deploy a partner service on this migrated host by doing a clustered service deployment. Continue migrating the remaining hosts in Cluster 1. After all the hosts in Cluster 1 are migrated to NSX-T, you can optionally deploy additional partner SVMs in Cluster 1 by doing either a host-based or a clustered service deployment.

The detailed procedure in this topic explains the host migration workflow for a single NSX-V prepared cluster, which has three hosts, as shown in the following figure. The procedure uses Approach 2 to migrate this Cluster 1 to NSX-T.

Example:

Figure 1. Host Group 1 (Cluster 1) Before Migration

Cluster 1 has three NSX for vSphere prepared hosts, and each host has one partner service virtual machine.

All hosts in this cluster are ESXi hosts. The Security Policies in your NSX-V environment redirect data traffic to partner service virtual appliances that provide a network introspection service to workloads. As NSX-V supports only a host-based service deployment, each host has a single partner service VM.

The following configuration settings are required for migrating hosts using Approach 2:
  • Host migration mode is set to Automated Maintenance.
  • Pause between groups is enabled.
  • Migration order across groups is set to serial.

Prerequisites

  • Verify that Edge migration has finished and all routing and services are working correctly.
  • In the vCenter Server UI, go to the Hosts and Clusters page, and verify that all ESXi hosts are in an operational state. Address any problems with hosts including disconnected states. There must be no pending reboots or pending tasks for entering and exiting maintenance mode.
  • Enable vSphere DRS on the cluster that is being migrated.
  • Enable vMotion on the VMkernel adapter of each host in the cluster.
  • Ensure that adequate spare capacity is available in the NSX-V cluster so that the migrating hosts can enter into a maintenance mode. If enough spare capacity is unavailable to migrate NSX-V workload VMs to other hosts in the cluster, additional security protection downtime is expected.

Procedure

  1. Run the following API request to create a temporary host group and move hosts 2 and 3 to this temporary group.
    POST https://{nsxt-mgr-ip}/api/v1/migration/migration-unit-groups
    In the request body of this POST API, specify the following details:
    • Name of the temporary host group
    • Migration units (IDs of hosts 2 and 3)
    • Migration state of the temporary group (must be disabled)

    For a detailed information about this API and an example POST API request, see the NSX-T Data Center API Guide.

    You can obtain the host IDs from the vCenter Server Managed Object Browser (MOB) at http://{vCenter-IP-Address}/mob, or run the following GET API to retrieve the host IDs:

    GET https://{nsxt-mgr-ip}/api/v1/fabric/discovered-nodes

    A temporary host group is created and displayed on the Migrate Hosts page. The original host group 1 (cluster 1) now contains only host 1.
  2. On the Migrate Hosts page, next to Host Migration Plan, click Settings and ensure that the settings are configured as follows:
    • Pause between groups: Enabled
    • Migration order across groups: Serial
  3. Migrate host 1 to NSX-T.
    1. Click Start to start the host migration.
      Workload VMs 1 and 2 are migrated to other hosts so that host 1 can enter into a maintenance mode. NSX-V partner SVM on host 1 is powered off before host 1 enters into a maintenance mode.

      Assume that VMs 1 and 2 are migrated to host 3 that is prepared with NSX-V. After the migration of host 1 is successful, the migration coordinator pauses for your next input.

    2. (Required) Deploy a partner service on host 1 by using the clustered deployment approach.

      At this stage, host-based service deployment is not supported. Deploying a partner service on host 1 is necessary to minimize security protection downtime. Remember, the security protection for NSX-V workloads that are running on hosts 2 and 3 is still intact. The partner must ensure that the migrated partner-specific Security Policies are available on the newly deployed partner SVMs on host 1.

      For detailed steps on deploying a partner service in NSX-T, see Deploy a Partner Service for Network Introspection. For example, specify the following configuration settings to deploy two partner service virtual machines (SVMs) on host 1:
      Configuration Value
      Deployment Type Clustered
      Host Host 1
      Clustered Deployment Count 2

      The value that you enter in the Clustered Deployment Count text box depends on the resource capacity that is available on the host. This scenario assumes that two partner SVMs can be deployed on Host 1. This value can be different in your environment.

      After this step, the cluster looks as shown in the following figure. The green colored host represents the migrated host.
      Figure 2. Host 1 is Migrated to NSX-T

      Host 1 is migrated to NSX-T and two partner service VMs are deployed on this host.
  4. Migrate host 2 and host 3 to NSX-T.
    1. Move host 2 and host 3 from the temporary host group to the original host group 1 by running the following POST API request:
      POST https://{nsxt-mgr-ip}/api/v1/migration/migration-unit-groups/{group-id}?action=add_migration_units

      Where: group-id is the ID of the destination host group (host group 1). In the POST API request body, specify the ID of hosts 2 and 3 that you want to add to the original host group 1.

      For a detailed information about this POST API and an example POST API request, see the NSX-T Data Center API Guide.

      Now, the original host group 1 contains hosts 1, 2 and 3 (in the given order), and the temporary host group is deleted.
    2. Select the check box next to the original host group 1, and then click Actions > Change Migration Order Within Group. Verify that the migration order within the group is set to Serial.
      If necessary, you can set the migration order in the original host group 1 to Parallel.
    3. Click Continue to resume the host migration.
      Host 2 is first migrated to NSX-T, and then host 3 is migrated. To put each migrating host into a maintenance mode, workload VMs on the migrating host are moved to either NSX-V hosts or NSX-T hosts. NSX-V partner SVM on the migrating host is also powered off before the host enters into a maintenance mode.
    After this step, all the hosts in host group 1 (cluster 1) are prepared with NSX-T. The cluster looks as shown in the following figure.
    Figure 3. All Hosts are Migrated to NSX-T

    All hosts are migrated to NSX-T, and hosts 2 and 3 have no NSX-T partner SVM.
  5. (Optional) Migrate some workload VMs from hosts 1 and 2 to host 3.
    For example, migrate VMs 4 and 5 to host 3, as shown in the following figure.
    Figure 4. Final Cluster 1 After Migration

    All Hosts in Cluster 1 are migrated to NSX-T.
  6. (Optional) After all the hosts in host group 1 are migrated to NSX-T, you can do either a host-based or a clustered service deployment.

    A host-based service deployment allows new network traffic to be protected by a local partner SVM on each host.

    Note: If you have network introspection service running on more than one NSX-V prepared cluster, you do not have to deploy the partner SVMs in the other clusters. The network traffic though the NSX-T workload VMs in the other clusters can use the partner SVMs in cluster 1 that you just migrated. The host migration workflow covered in this procedure is required only for the first cluster. You can migrate the remaining clusters by using the standard host migration procedure.

What to do next

Delete the partner service deployment in NSX-V. Remember, you can delete the partner SVMs only at a cluster level. That is, you can delete service deployment only after all the hosts in the host group 1 are migrated to NSX-T. Complete the following steps to delete the service deployment in NSX-V:
  1. Log in to the vSphere Client and navigate to Networking and Security > Installation and Upgrade > Service Deployment.
  2. Select the deployed partner service, and click Delete.