NSX-V to NSX-T migration overview

This documentation provides a validated approach and guidance for existing IBM Cloud® for VMware Solutions customers with VMware vCenter Server® with NSX-V instances. In that way, they can move and migrate their workloads to new vCenter Server with NSX-T™ instances (also referred as V2T migration). This documentation is not primarily aimed at customers that want to migrate on-premises workloads to IBM Cloud, although some of the approach and guidance is applicable.

While VMware documentation describes a number of migration approaches, only the coexist or lift-and-shift approaches are validated by IBM Cloud. In the co-exist approach, NSX-V, and NSX-T are run side by side and new workloads are placed on the new NSX-T environment and old workloads are decommissioned on the NSX-V environment. When the NSX-V environment is empty, it can be de-provisioned. This approach is not discussed further in the documentation, but it can be a validated option if you want to follow this path.

In the lift-and-shift approach, the IBM Cloud automation is used to deploy a new vCenter Server instance on the same or different VLANs. With this action, you can perform both NSX-V to NSX-T migration and workload migration.

The lift-and-shift migration approach enables:

• Flexibility to plan the migration based on your workload requirements.
• You to adopt a modular migration approach, for example, partial subnet evacuation.
• You to configure a different network topology in the NSX-T environment.
• Fail-back of a migration wave, as the existing NSX-V environment is still running.
• Over time, you can gradually migrate specific parts of the NSX-V workloads.
• Logically extending networks between both environments and move the workloads gradually from NSX-V to NSX-T.

The journey from NSX-V to NSX-T requires careful planning and preparation. You must be familiar with NSX-T concepts and administration tasks before any migrations. This journey must involve the following steps:

• Education - Training for the team who migrates to NSX-T and then runs NSX-T.
• Migration planning and preparation - Review the current NSX-V environment to understand the complexity of the migration, and key business drivers that impact migration. Select the topology for the target NSX-T environment.
• Target platform selection, deployment, and configuration - This step also includes the setting-up of migration tools such as L2 bridging or VMware HCX. Or also third-party tools such as SPJ's cITopus or ReSTNSX's Migration Assistance Tool.
• Configuration migration - These tasks include the setting-up of overlay components, which includes NSX-T segments, routing, load balancing, edge firewall, distributed firewall, and tagging. Configuration migration can be done manually through scripting, such as Terraform or third-party tools such as SPJ's cITopus.
• Workload migration - This step includes layer 2 network stretching, if required, and virtual machine migration. Migration techniques include VMware HCX migrations or Advanced vCenter vMotion.

An example of high-level migration workflow that uses the lift-and-shift migration approach with NSX-T L2 Bridge is as follows:

• Deploy the new vCenter Server with NSX-T instance.
• Create your required NSX-T network topology and configure the necessary network services.
• Configure an NSX-T Edge bridge to extend the NSX-V VXLAN/logical switch/virtual wire to an overlay segment in NSX-T.
• Use the VMware Migration Coordinator to migrate (copy across) the Distributed Firewall (dFW) configuration.
• The dFW only migration mode of the migration coordinator must be run only one time. After the dFW configuration is migrated to NSX-T, do not update the dFW configuration in the NSX-V environment.
• Switch the default gateway to the NSX-T environment.
• Use NSX-T Edge bridge and vSphere vMotion to migrate workload VMs to the overlay segment in NSX-T.
• Migrate the Security Tags to the workload VMs in NSX-T.
• Continue with all NSX-V logical switches until all VMs be evacuated from the NSX-V environment.
• Decommission the old vCenter Server with NSX-V environment.

Depending on the source environment complexity and the skills, experience and time commitments of your team you might want to engage professional services. This action can develop a migration plan and also run the migration for you.