After you have imported the configuration from your NSX Data Center for vSphere environment, you must review and resolve the reported configuration issues before you can continue with the migration.

On the Resolve Configuration page, two types of configuration issues are reported.
Blocking Issues (if any)
As the name suggests, these issues block the migration, and they must be fixed for the migration to proceed. You might have to change the configurations in your NSX-v environment before you can migrate to NSX-T Data Center.
Warnings
These configuration issues are organized into several categories, and each category can have one or more configuration items. You should provide inputs to fix the warning messages that are displayed for the configuration items, or choose to skip the warnings, if needed.

Procedure

  1. On the Resolve Configuration page, if you find any blocking issues, fix them in the NSX-v environment before you can proceed with the migration.

    After making the required changes in the NSX-v environment, return to the migration coordinator. Go to the Import Configuration page, and click Rollback. Click Start to import the updated NSX-v configuration.

    If you did not find any blocking issues that require a change in the NSX-v environment, proceed to the next step.
  2. Review the warnings and issues reported in each category.
  3. Click each issue and provide input.

    Each issue can cover multiple configuration items. For each item there might be one or more possible resolutions to the issue, for example, skip, configure, or select a specific value.

    For issues that apply to multiple configuration items, you can provide input for each item individually, or select all and provide one answer for all items.

  4. After the input is provided, a Submit button is displayed on the Resolve Configuration page. Click Submit to save your progress.
  5. When you have provided input for all configuration issues, click Submit.
    The input is validated. You are prompted to update any invalid input. Additional input might be required for some configuration items.
  6. After you have submitted all requested input, click Continue to proceed to the Migrate Configuration page.

Example: Configuration Issues

Migration coordinator shows warning messages if it detects the following issues in your NSX-T environment:
  • A missing NSX-T VLAN segment corresponding to the Distributed Virtual Port Group (DVPG) VLAN ID in your NSX-v environment.
  • A missing NSX-T overlay segment corresponding to the VNI of the Logical Switch in the NSX-v environment.

To resolve this configuration issue, you can either skip creating the missing NSX-T segments or cancel the migration. If you choose to cancel the migration, create the missing segments in NSX-T by running the following PATCH API request, and start the migration again.

PATCH https://{policy-manager}/policy/api/v1/infra/segments/{segment-id}?force=true

For example, to create a segment "App" with overlay ID "5001", the API URL and the payload of the API request is as follows:

PATCH https://{policy-manager}/policy/api/v1/infra/segments/App?force=true 
{ "type" : "ROUTED",
  "subnets" : [ {” "gateway_address" : "172.16.20.1/24",
    "network" : "172.16.20.0/24""
    "} ],
  "connectivity_path" : "/infra/tier-0s/T0-GW-01",
  "transport_zone_path" : "/infra/sites/default/enforcement-points/default/transport-zones/
   1b3a2f36-bfd1-443e-a0f6-4de01abc963e",
  "overlay_id":5001,
  "admin_state" : "UP",
  "replication_mode" : "MTEP",
  "resource_type" : "Segment",
  "id" : "App",
  "display_name" : "App",
  "path" : "/infra/segments/App",
  "relative_path" : "App",
  "parent_path" : "/infra" }

If you choose to skip creating the missing NSX-T VLAN or overlay segments, the VM vNICs that are connected to the DVPG VLANs or the Logical Switches in the NSX-v environment lose networking after the workload VMs are migrated using vSphere vMotion. In this case, the migration coordinator does not migrate the DFW rules and Security Groups that are associated with the skipped segments.

For example, you might not want to create the missing segments in the following situations:
  • Port groups on the vSphere Distributed Switch (VDS) have only VMkernel ports. So, no requirement to create VLAN segments.
  • Port groups from another VDS that you do not want to migrate.
  • NSX-v Logical Switch with no workload VMs attached to it. For instance, a transit Logical Switch between an Edge Services Gateway and the Distributed Logical Router.