Managing Virtual Extensible LANs

This chapter contains the following sections:

About VXLANs

A virtual extensible LAN (VXLAN) defines a 24-bit LAN segment identifier to provide segmentation at cloud scale and an architecture that expands cloud deployments with repeatable pods in different Layer 2 (L2) domains. A VXLAN can also enable the migration of virtual machines (VMs) between servers across Layer 3 networks.

A VXLAN creates LAN segments by overlaying the original MAC (L2) frame in IP encapsulation from the VM within the Virtual Ethernet Module (VEM).

Each VEM is assigned an IP address, which is used as the source IP address when MAC frames are encapsulated and sent over the network. You can have multiple VMkernel NICs (also referred to as virtual network adapters or vmknics) per VEM that are used as sources for this encapsulated traffic. The encapsulation carries the 24-bit VXLAN identifier that scopes the MAC address of the payload frame.


Note

VMkernel NICs are used to manage physical NICs (pNICs) on a host server to connect the virtual network to the physical network.

The connected VXLAN is indicated within the port profile configuration of the virtual network interface card (vNIC) and is applied when the VM connects. Each VXLAN uses an assigned IP multicast group to carry broadcast traffic within the VXLAN segment.

In Cisco UCS Director, you can configure VXLANs on the Cisco Nexus 1000 switch.


Note

For more detailed information about VXLANs and configuration guidelines for VXLANs, see the Cisco NX-OS Software Configuration Guides.

Creating a VXLAN

    Step 1   Choose Physical > Network.
    Step 2   On the Network page, choose the pod.
    Step 3   Expand the pod, and select the network device to be configured.
    Step 4   Click VXLAN Table.
    Step 5   Click Create VXLAN.

    Alternately, you can choose the command from the More Actions drop-down list.

    Step 6   In the Create VXLAN screen, complete the required fields, including the following:
    Name Description

    Bridge Name field

    The bridge domain name for the virtual extensible LAN (VXLAN).

    VXLAN Id field

    The VXLAN ID number within the valid range.

    Mode Unicast check box

    Check the check box to enable a unicast-only VXLAN.

    With a unicast-only VXLAN, the Virtual Supervisor Module (VSM) knows which VEMs have Virtual Machines (VMs) attached to a particular VXLAN segment and distributes that information to all Virtual Ethernet Modules (VEMs). Each VEM receives a per-VXLAN list of destination IP addresses to use for flooding purposes.

    Distribution learning MAC check box

    Check the check box to distribution learning for MAC addressing.

    MAC learning enables the distribution of the MAC addresses learned on one line card to the other line cards.

    Copy Running configuration to Startup configuration check box

    Check the check box to copy the running VXLAN configuration to the startup configuration.

    Step 7   Click Submit.

    Encapsulating a VXLAN

    You can configure VMkernel NICs (vmknics) for virtual extensible LAN (VXLAN) encapsulation by running the following procedure.


    Note

    Identify a VLAN to be used for transporting VXLAN encapsulated traffic and ensure that it is configured on the uplink port profile for all VEMs on which the VXLAN can be configured.

      Step 1   Choose Physical > Network.
      Step 2   On the Network page, choose the pod.
      Step 3   Expand the pod, and select the network device to be configured.
      Step 4   Click VXLAN Table.
      Step 5   Select the VXLAN domain to be encapsulated.
      Step 6   Click Encapsulate VXLAN.

      Alternately, you can choose the command from the More Actions drop-down list.

      Step 7   In the Encapsulate VXLAN screen, complete the required fields, including the following:
      Name Description

      Select Port Profile drop-down list

      Choose the port profile that you want to use for the VXLAN.

      VLAN ID Select button

      Click Select. In the Select dialog box, check the check box for the VLAN ID that you want encapsulated and click Select.

      Copy Running configuration to Startup configuration check box

      Check the check box to copy the running VXLAN configuration to the startup configuration.

      Step 8   Click Submit.

      Assigning a VXLAN to a Port Profile

        Step 1   Choose Physical > Network.
        Step 2   On the Network page, choose the pod.
        Step 3   Select the network device to be configured.
        Step 4   Click VXLAN Table.
        Step 5   Select the VXLAN domain to be assigned to a port profile.
        Step 6   Click Assign VXLAN to a Port Profile.

        Alternately, you can choose the command from the More Actions drop-down list.

        Step 7   In the Assign VXLAN screen, complete the required fields, including the following:
        Name Description

        Select Port Profile drop-down list

        Choose the port profile name for the VXLAN assignment.
        Note   

        Ensure that the access VLAN is enabled for a VXLAN capability in the port profile that you are using for the VXLAN. For more information, see Creating a Port Profile.

        Copy Running configuration to Startup configuration check box

        Check the check box to copy the running VXLAN configuration to the startup configuration.

        Step 8   Click Submit.

        Unassigning a VXLAN from a Port Profile

          Step 1   Choose Physical > Network.
          Step 2   On the Network page, choose the pod.
          Step 3   Expand the pod and select the network device to be configured.
          Step 4   Click VXLAN Table.
          Step 5   Select the VXLAN domain to be unassigned from a port profile.
          Step 6   Click Unassign VXLAN from Port Profile.

          Alternatively, you can choose the command from the More Actions drop-down list.

          Step 7   In the Unassign VXLAN dialog box, complete the required fields, including the following:
          Name Description

          Select Port Profile drop-down list

          Choose the port profile from which you need to unassign the VXLAN.

          Copy Running configuration to Startup configuration check box

          Check the check box to copy the running VXLAN configuration to the startup configuration.

          Step 8   Click Submit.

          Removing a VXLAN


          Note

          Executing this procedure moves the ports to the default VLAN.

            Step 1   Choose Physical > Network.
            Step 2   On the Network page, choose the pod.
            Step 3   Expand the pod and select the network device to be configured.
            Step 4   Click VXLAN Table.
            Step 5   Select the VXLAN to be removed.
            Step 6   Click Remove VXLAN.
            Step 7   In the Remove VXLAN screen, complete the following field:
            Name Description

            Copy Running configuration to Startup configuration check box

            Check the check box to copy the running VLAN configuration to the startup configuration.

            Step 8   Click Submit.