In addition to the Layer 2 fabric mentioned above, Layer 3 fabrics are also part of the Dell Enterprise SONiC offering.
Layer 3 fabric benefits:
- Flexibility
- Reliability and redundancy
- Edge and fabric scalability
- Virtualization support
- Multitenancy
The following figure shows a typical leaf and spine fabric. In this topology, the leaf layer provides Layer 2 connections downstream to the end-hosts and Layer 3 connections to the spine switches.
Deployment best practices
Whenever deploying a Layer 3 fabric, the following best practice guidelines should be followed:
- Implement routing redundancy using equal cost multipathing (ECMP) between the switch interlinks, that is, leaf and spine links. This feature helps mitigate link congestion and provides efficient link load sharing capabilities.
- Enable "link state tracking," which helps to minimize switch fail-over time.
- As a minimum two active links between leaf and spine switches should always be used to ensure link redundancy.
- Border Gateway Protocol (BGP) scales better for cloud and large enterprise deployments.
- Configure jumbo frames to address any potential issues with packet size.
For more information about a Dell Enterprise SONiC Layer 3 deployment, see Enterprise SONiC Distribution by Dell Technologies - Layer 3 Fabric.