Juniper QFX5100 Series

Chapter 5. Virtual Chassis Fabric

A growing trend in the networking industry is to move away from traditional architectures such as Layer 2–only access switches or putting both Layer 2 and Layer 3 in the distribution layer. The next logical step for ubiquitous Layer 2 and Layer 3 access with ease of management is to create an Ethernet fabric.

Virtual Chassis Fabric (VCF) is a plug-and-play Ethernet fabric that offers a single point of management and many, many features. Think of a 3-stage Clos topology with the look and feel like a single logical switch; this is another good way to visualize VCF.

Overview

It’s a common myth that a high-performance, feature-rich network is difficult to manage. This usually stems from the fact that there are many factors that the administrator must worry about:

• Performance

• Scale

• Latency

• High availability

• Routing protocols

• Equal cost multipathing

• Layer 2 and Layer 3 access

• Lossless Ethernet

• Software upgrades

• Management

Such a laundry list of tasks and responsibilities is often daunting to a small or medium-sized company with a minimal IT staff, and indeed, without assistance, would be difficult to administer. VCF was created specifically to solve this problem. It provides an architecture by which a single person can manage the entire network as if it were a single device, without sacrificing the performance, high availability, or other features.

It’s easy to assume from the name that VCF has a lot of roots in the original Virtual ...