Juniper XRE200 -, Hardware Manual

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The XRE200 External Routing Engine (model number: EX-XRE200) is used to create a Virtual Chassis
composed of Juniper Networks EX8200 Ethernet Switches. A Virtual Chassis is multiple switches connected
together that operate as a single network entity. The advantages of connecting multiple EX8200 switches
into a Virtual Chassis include better-managed bandwidth at a network layer, simplified configuration and
maintenance because multiple devices can be managed as a single device, and a simplified Layer 2 network
topology that minimizes or eliminates the need for loop prevention protocols such as Spanning Tree
Protocol (STP).
An EX8200 Virtual Chassis supports up to two external Routing Engines and up to four EX8200 switches.
A second XRE200 External Routing Engine can be added to the Virtual Chassis configuration to provide
external Routing Engine redundancy. Juniper Networks EX8208 and EX8216 Ethernet Switches can be
part of the same EX8200 Virtual Chassis.
Benefits of the XRE200 External Routing Engine
Enables configuring of EX8200 switches in a Virtual Chassis—The XRE200 External Routing Engine enables
you to configure EX8200 switches in a Virtual Chassis and manage and operate them as a single network
entity.
You connect Virtual Chassis ports (VCPs) on an XRE200 External Routing Engine to the management
(labeled MGMT) ports on the internal Routing Engines of EX8200 switches to form an EX8200 Virtual
Chassis. The Virtual Chassis is formed automatically when these connections are established.
Software
All devices in an EX8200 Virtual Chassis run the Juniper Networks Junos operating system (Junos OS).
The same Junos OS code base that runs on the devices in the EX8200 Virtual Chassis also runs on many
other Juniper products, including all EX Series switches, the Juniper Networks J Series, M Series, MX Series,
and T Series routers, and SRX Series Services Gateways.
In an EX8200 Virtual Chassis, most Routing Engine tasks for all switches in the Virtual Chassis run on the
XRE200 External Routing Engine. The internal Routing Engines continue to be responsible for functions
local to their own switches, such as environmental monitoring, system loading, and power management.
The internal Routing Engines communicate with the external Routing Engine by using the Virtual Chassis
Control Protocol (VCCP).
You must configure all switches and external Routing Engines that will be part of the same EX8200 Virtual
Chassis to run the same version of Junos OS before connecting the devices into a Virtual Chassis.
After you connect an EX8200 Virtual Chassis, all switches and external Routing Engines that are part of
the Virtual Chassis should be upgraded simultaneously.
An EX8200 Virtual Chassis supports a subset of the software features available for the EX8200 switch.
For a list of software features available on an EX8200 Virtual Chassis, see EX Series Virtual Chassis Software
Features Overview.
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