Configuring Non-Clos Small Data Center Automation

Non-Clos topology is used for small scale, VCS-like deployments, and consists of four interconnected racks containing two devices each, for a maximum scale of eight devices. The devices are connected uisng eth 0/46, eth 0/47 and eth 0/48.

There are four steps to configuring a Non-Clos Small Data Center topology; Create the fabric, Register the devices, Validate and Add the devices, and Provision the configuration on the devices. The following steps describe how to configure a small data center topology.

Create the Fabric.

$ efa fabric create --name extr-fabric  --type non-clos

Add a device or devices to the Fabric. The user must provide device credentials as part of this command if the devices are not already registered with the inventory.
```
$ efa fabric device add --name extr-fabric --ip 10.24.80.134 --rack room1-rack1 --username admin --password password 
$ efa fabric device add --name extr-fabric --ip 10.24.80.135 --rack room1-rack1 --username admin --password password

$ efa fabric device add --name extr-fabric --ip 10.25.225.163 --rack room1-rack2 --username admin --password password 
$ efa fabric device add --name extr-fabric --ip 10.25.225.167 --rack room1-rack2 --username admin --password password
```
A device must be registered with Inventory Service before being added to a Fabric. Fabric Service supports IP numbered configuration. Each interface on a link between leaf and spine is assigned an IP address. eBGP peering use these IP addresses.
Multiple devices can be added to an existing fabric using the efa fabric device add-bulk command. If a username and password are provided, then the devices will be auto registered with the inventory service.
```
$ efa fabric device add-bulk --name extr-fabric --rack room1-rack1 --ip 10.24.80.134,10.24.80.135 --rack room1-rack2 --ip 10.25.225.163,10.25.225.167
```
Use the efa fabric configure command to validate and configure the Fabric Topology.
```
$ efa fabric configure --name extr-fabric
```
During each of the steps; create, add, and configure, Clos topology validations are performed. If the validation contains errors, the errors are reported to the user. The encountered Fabric topology errors can be exported to a CSV/DOT file.
In Small Data Center Automation, the following topology validations are performed:
- A rack may contain up to 2 devices.
- A rack contains only SLX9140 devices.
- Maximum number of racks supported per fabric is 4.
- Each rack should be connected to at least one other rack.
- Devices within a rack must be connected via 0/46, 0/47, and 0/48.
If the addition of devices to a Fabric is successful, then the configuration is pushed to all the devices of the Fabric using the efa fabric configure command above.

Use the following commands to display detailed information about the Small Data Center topology and configuration.

efa fabric export: Export fabric details to a .CSV file.
efa fabric show: Display the details of the fabric.
efa fabric topology show physical: Displays physical connectivity of the devices in a fabric.
efa fabric topology show underlay: Displays the underlay connectivity - the BGP neighborship and the state of BGP sessions of the devices in a fabric.
efa fabric topology show overlay: Displays the overlay connectivity of the devices in a fabric.