The 3-stage topology has two layers of
		devices: Leaf and Spine. All links between Leaf and Spine must be connected. Spine nodes
		should not be interconnected. 
		There are four steps to configuring a
			three-stage topology: create the fabric, register the devices, validate and add the
			devices, and provision the configuration on the devices.The following is an example
				of a three-stage fabric. 
			 
	 - 
				Create the Fabric.
			
- 
				Add a device or devices to the
					Fabric. 
			
- 
				Validate the Fabric
					Topology.
				During the addition of a device to a Fabric
					and during Fabric configuration, Clos topology validations are performed. If the
					validation contains errors, the errors are reported to the user as a response to
					the  fabric device add or  fabric configure
					operations. Any Fabric topology errors can be exported to a CSV or DOT file. The
					following topology 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 L
							node are not connected to each other.
- Spine nodes are not
							connected to each other.
- Super-spine nodes are not
							connected to each other.
- If a Leaf node is marked
							as "multi-homed", then the node must have an MCT neighbor.
- If a Leaf node is marked
							as "single-homed", then the node is not connected to other Leaf
							nodes.
- If a Border Leaf node is
							marked as "multi-homed", then the node must have an MCT neighbor.
- If a Border Leaf node is
							marked as "single-homed", then the node 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).
 
- 
				Configure the Fabric on the
					devices.
			
Example
Example: Create the fabric.
			
efa fabric create --name stage3
		Example
Example: Add a device 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
Example: Configure the fabric on the
			device.
efa fabric configure --name stage3