Distributed Switch to Standard Switch Migrations

I was looking for a way to migrate VMkernel adapters back from a VDS to a VSS. This was because I am testing various upcoming releases of vCenter Server 8.0 and vSphere with Tanzu. vSphere with Tanzu, if you do not use NSX-T, requires a distributed switch and distributed portgroups. After building out some test environments, I wanted to roll back a distributed switch (VDS) configuration to a standard vSwitch (VSS) configuration. The process seems to have changed a few times in the past, and I could not find anything that demonstrated how to do task on vSphere 7.0. Thus I decided to create this blog post.

The first thing to keep in mind is that the uplinks on the VSS must provide access to the same networks as the uplinks on the VDS for the migration to succeed. The nice thing is that for the management network, if the migration from VDS to VSS fails, vCenter will roll back the change.

Below is my setup. Note that there are only 3 VMkernel ports per host; management, vMotion and vSAN. Note also that the management network is on a different uplink to the vMotion and vSAN networks. I have highlighted these below, as you may have to do some Teaming and Failover configuration once the migration from VDS to VSS has taken place. This is because there is no way to do a teaming / failover selection during the migration itself.

This is my management distributed portgroup which uses vmnic2.

These are the vMotion and vSAN distributed portgroups which use vmnic0.

From a VSS perspective, vmnic1 is connected to the same network as vmnic0, whilst vmnic3 is connected to the same network as vmnic2. Let’s begin by migrating the vSAN network. On the Standard Switch: vSwitch0, click on the “…” breadcrumbs to the right of the “Manage Physical Adapters” as shown in blue below. This will open a menu, where one of the menu items is “Migrate VMkernel Adapter”:

You are now presented with a set of VMkernel adapters from the VDS which are available for migration. Simply select the adapter you wish to migrate and click next. In my example, I chose to migrate vmk2, the vSAN adapter.

The next step is to provide a label for the VMkernel on the VSS. I called it vSAN-VSS-30. Note that the VLAN ID associated with the VMkernel adapter from the VDS is included automatically.

At the Ready to complete screen, review the configuration and click Finish. The VMkernel adapter should now appear on the VSS as shown below. However, not that the VMkernel adapter has been associated with both uplinks on the VSS, which may not be desirable.

To ensure that the vSAN VMkernel adapter is associated with vmnic1 only, click on the “…” breadcrumbs which appear next to the network label “vSAN-VSS-30”. This will provide an option to “Edit Settings“. This includes modifying the Teaming and failover configuration.

Once the settings are open, navigate to the Teaming and failover section. Notice that both adapters are active, as shown above. The objective is to move the vmnic3 to the Unused adapters section.

To move an adapter to unused, first select the Override button. This will allow you to select an adapter and move it between categories. Next select the vmnic3 adapter and click on “Move Down” until it appears under Unused adapters.

Click OK to confirm the failover order. The VMkernel adapter should now show that it is using the correct uplink.

And that completes the steps on how to migrate a VMkernel adapter from a VDS (distributed switch) to a VSS (standard switch).

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