Before you uninstall NSX-T Data Center from an ESXi host, verify that you have appropriate network mappings for uninstall configured. The mappings are required if the ESXi host has VMkernel interfaces connected to N-VDS.

The uninstall mapping determines where the interfaces are connected after the uninstall. There are uninstall mappings for physical interfaces (vmnicX) and VMkernel interfaces (vmkX). When you uninstall, VMkernel interfaces are moved from their current connections to the port groups specified in the uninstall mapping. If a physical interface is included in the uninstall mapping, the physical interface is connected to the appropriate vSphere Distributed Switch or vSphere Standard Switch based on the destination port group of the VMkernel interfaces.
Caution: Uninstalling NSX-T Data Center from an ESXi host is disruptive if the physical interfaces or VMkernel interfaces are connected to N-VDS. If the host or cluster is participating in other applications such as vSAN, those applications might be affected by the uninstall.
There are two places that you can configure network mappings for uninstall.
  • In the transport node configuration, which applies to that host.
  • In a transport node profile configuration, which can then be applied to a cluster.
    Note: You must have a compute manager configured to apply a transport node profile to a cluster.

If a compute manager is configured, a host can have both a transport node configuration and a transport node profile configuration. The most recently applied configuration is active. Verify that the network mappings for uninstall are correctly configured on the active configuration.

Transport node configuration on a node cannot be overriden if underlying segments or VMs are connected to that transport node. For example, consider a two ESXi host cluster, where host-1 is configured as transport-node-1, but host-2 is unprepared. Segments and VMs are connected to transport-node-1. After preparing host-1 as a transport node (associated to transport-zone-1), if you apply a transport node profile to that cluster (associated to transport-zone-2), then NSX-T does not override the transport node configuration with the transport node profile configuration. To successfully override configuration on host-1, power off the VMs and disconnect the segment before applying the transport node profile to associate host-1 to transport-zone-2 and disassociate it from transport-zone-1.

In this example, the cluster cluster-1 has transport node profile TNP-1 applied to it. The host tn-1 is displaying Configuration Mismatch. This mismatch message indicates that a different configuration has been applied to tn-1 after the transport node profile was applied. Transport node tn-2 uses the network mappings from the transport node profile, and transport node tn-1 uses its own configuration.

Prerequisites

  • Verify that you have appropriate port groups configured to use in the uninstall mapping. You must use vSphere Distributed Switch ephemeral port groups or vSphere Standard Switch port groups.

  • Configure a compute manager if you want to use a vSphere Distributed Switch port group in the uninstall mappings for a standalone ESXi host. See Add a Compute Manager. If there is no compute manager configured, you must use a vSphere Standard Switch port group.

Procedure

  1. From a browser, log in with admin privileges to an NSX Manager at https://<nsx-manager-ip-address>.
  2. Select System > Fabric > Nodes > Host Transport Nodes.
  3. For each host (on N-VDS Switch) you want to uninstall, verify that the network mapping for uninstall includes a port group for each VMkernel interface that is on N-VDS. Add any missing mappings.
    Important:
    • The port group in the network mapping for uninstall must be a vSphere Distributed Switch ephemeral port group or a vSphere Standard Switch port group.
    1. To view VMkernel interfaces, log in vCenter Server, select the host, and click Configure > VMkernel Adapters.
    2. If the transport node configuration is the active configuration, select the host and click Edit (for standalone hosts) or Configure NSX (for managed hosts). Click Next, then click Network Mappings for Uninstall. View the mappings in the VMKNic Mappings and Physical NIC Mappings tabs.
    3. If the transport node profile is the active configuration, click the name of the transport node profile for the cluster in the NSX Configuration column and click Edit. On the Host Switch tab, click Network Mappings for Uninstall. View the mappings in the VMKNic Mappings and Physical NIC Mappings tabs.
  4. For each host (on a VDS Switch) you want to uninstall:
    1. As the NSX Manager UI does not allow you to configure network mapping for install or uninstall when the host switch is vSphere Distributed Switch, ensure that you migrate back any VMkernel adapters connected to NSX port groups to either a Distributed Virtual port group or a VSS port group from vCenter Server. Uninstallation fails if there are any VMkernel adapters attached to an NSX port groups on VDS.