Logical switches attach to single or multiple VMs in the network. The VMs connected to a logical switch can communicate with each other using the tunnels between hypervisors.

Note that there is a delay of up to 4 minutes in creating the first logical switch if you enable the lockdown mode.

Prerequisites

  • Verify that a transport zone is configured. See the NSX-T Data Center Installation Guide.
  • Verify that fabric nodes are successfully connected to NSX-T Data Center management plane agent (MPA) and NSX-T Data Center local control plane (LCP).

    In the GET https://<nsx-mgr>/api/v1/transport-nodes/<transport-node-id>/state API call, the state must be success. See the NSX-T Data Center Installation Guide.

  • Verify that transport nodes are added to the transport zone. See the NSX-T Data Center Installation Guide.
  • Verify that the hypervisors are added to the NSX-T Data Center fabric and VMs are hosted on these hypervisors.
  • Familiarize yourself with the logical switch topology and BUM frame replication concepts. See Logical Switches in Manager Mode and Understanding BUM Frame Replication Modes.

  • Verify that Manager mode is selected in the NSX Manager user interface. See NSX Manager. If you do not see the Policy and Manager mode buttons, see Configure the User Interface Settings.

Procedure

  1. With admin privileges, log in to NSX Manager.
  2. Select Networking > Logical Switches > Switches > Add.
  3. Enter a name for the logical switch and optionally a description.
  4. Select a transport zone for the logical switch.
    VMs that are attached to logical switches that are in the same transport zone can communicate with each other.
  5. Enter the name of an uplink teaming policy.
  6. Set Admin Status to either Up or Down.
  7. Select a replication mode for the logical switch.
    The replication mode (hierarchical two-tier or head) is required for overlay logical switches, but not for VLAN-based logical switches.
    Replication Mode Description
    Hierarchical two-tier

    The replicator is a host that performs replication of BUM traffic to other hosts within the same VNI.

    Each host nominates one host tunnel endpoint in every VNI to be the replicator. This is done for each VNI.

    Head Hosts create a copy of each BUM frame and send the copy to each tunnel endpoint it knows about for each VNI.
  8. (Optional) Specify a VLAN ID or ranges of VLAN IDs for VLAN tagging.
    To support guest VLAN tagging for VMs connected to this switch, you must specify VLAN ID ranges, also called trunk VLAN ID ranges. The logical port will filter packets based on the trunk VLAN ID ranges, and a guest VM can tag its packets with its own VLAN ID based on the trunk VLAN ID ranges.
  9. (Optional) Click the Switching Profiles tab and select switching profiles.
  10. Click Save.
    In the NSX Manager UI, the new logical switch is a clickable link.

What to do next

Attach VMs to your logical switch. See Connecting a VM to a Logical Switch in Manager Mode.