Configure a 3-Stage Clos Fabric

The 3-stage topology has 2 layers of devices: leaf and spine. All links between leaf and spine must be connected. Spine nodes are not interconnected.

About this task

Tip

Tip

If any devices in a fabric are in "admin-down" state, use of the following commands in that same fabric will not add or delete devices in the fabric: efa fabric device add-bulk and efa fabric device remove.

Procedure

  1. Create the fabric.
    efa fabric create
  2. Add a device to the fabric.
    efa fabric device add

    A device must be registered with the Inventory Service before you can add it to a fabric. However, if you provide a user name and password when you run the command, then the devices are automatically registered with the Inventory Service. See the examples at the end of this procedure.

    You can add multiple devices by using the efa fabric device add-bulk command.

    Tip

    Tip

    To validate fabric port-link status, complete the following operations before running the efa fabric device add-bulk command:
    1. Run the efa inventory device register –ip <list of device-ips>​ command.
    2. Run the efa inventory device interface list –ip <device-ip> command.

      The efa inventory device interface list –ip <device-ip> displays the list of interfaces and details for the specified IP address, including the application state that indicates whether the device configuration is synchronized with XCO or has drifted (refreshed or deleted).

      1. Verify port link status (up or down) in Admin Status and Oper Status fields.
      2. Confirm they are as expected.
      3. If not, manually check for physical cabling and fix any issues. Continue with the efa fabric device add-bulk operation.
  3. Configure the fabric.
    efa fabric configure
    Topology validation occurs during the addition of a device and during fabric configuration. The following validations are performed.
    • Leaf nodes must connect to all the spine nodes.
    • A spine node must connect to all the leaf nodes.
    • A border leaf node connects to all the spine nodes.
    • A spine node connects to all the border leaf .
    • No more than two leaf nodes connect to each other.
    • No more than two border leaf nodes connect to each other.
    • Border leaf node and leaf node are not connected to each other.
    • Spine nodes are not connected to each other.
    • Super-spine nodes are not connected to each other.
    • A leaf node marked as "multi-homed" must have an MCT neighbor.
    • A leaf node marked as "single-homed" is not connected to other leaf nodes.
    • A border beaf node marked as "multi-homed" must have an MCT neighbor.
    • A border leaf node marked as "single-homed" is not connected to other border leaf nodes.
    • Device role (such as leaf, border-leaf, spine, or super-spine) is validated for a given device platform type (for example, SLX 9840 cannot be added as a leaf).
    Tip

    Tip

    The validation process reports any errors as a response to the efa fabric device add or efa fabric configure operations. You can use the efa fabric error show command to export these errors to a CSV file.
    Note

    Note

    You cannot change fabric settings after you add devices to the fabric, with the following exceptions: --md5-password-enable, --md5-password, --bgp-dynamic-peer-listen-limit, and --single-rack-deployment settings.

Example

This example creates the fabric.
efa fabric create --name stage3

Example

This example adds multiple devices to the fabric.
efa fabric device add-bulk --leaf 10.20.50.205,10.20.50.206,10.20.50.207 
--spine 10.20.50.203,10.20.50.204 --name stage3 --username admin 
--password password

Example

This example configures the fabric.
efa fabric configure --name stage3