Juniper JUNOS OS 10.4 - FOR EX REV 1 Manual page 1022

Complete Software Guide for Junos
Requirements
Overview and Topology
918
®
OS for EX Series Ethernet Switches, Release 10.4
This example describes how to configure a Virtual Chassis with a master and backup in
a single wiring closet:
Requirements on page 918
Overview and Topology on page 918
Configuration on page 920
Verification on page 920
Troubleshooting the Virtual Chassis on page 921
This example uses the following hardware and software components:
Junos OS Release 9.0 or later for EX Series switches
One EX4200-48P switch
One EX4200-24T switch
One XFP uplink module
Before you begin, be sure you have:
Rack-mounted the switches. See Mounting an EX4200 Switch.
1.
Installed the uplink module. See Installing an Uplink Module in an EX4200 Switch.
2.
Cabled the switches. See Connecting a Virtual Chassis Cable to an EX4200 Switch.
3.
A Virtual Chassis configuration allows you to accommodate the networking needs of a
growing office. The default configuration of a two-member Virtual Chassis includes a
master and a backup switch. In addition to providing more access ports than a single
EX4200 switch can provide, a Virtual Chassis configuration provides high availability
through redundancy.
This example shows a Virtual Chassis configuration composed of two EX4200 switches.
One of the switches has an uplink module with ports that can be configured to connect
to a distribution switch or customer edge (CE) router or that can be configured as Virtual
Chassis ports (VCPs) to interconnect with a member switch that is located too far for
the dedicated VCP cabling. (The network interfaces on EX4200-24F switches can also
be configured as VCPs.) For information on configuring the uplink ports as trunk ports to
a distribution switch, see "Configuring Gigabit Ethernet Interfaces (CLI Procedure)" on
page 1284. For an example of configuring uplink ports as VCPs, see "Example: Configuring
an EX4200 Virtual Chassis Interconnected Across Multiple Wiring Closets" on page 932.
By default, after you interconnect the switches with the dedicated VCPs and power on
the switches, the VCPs are operational. The mastership priorities and member IDs are
assigned by the software. The software elects a master based on several criteria, including
how long a member switch has belonged to the Virtual Chassis configuration. For
additional details, see "Understanding How the Master in an EX4200 Virtual Chassis Is
Copyright © 2010, Juniper Networks, Inc.