To Next Page

To Previous Page

NOTE: We recommend that you install two host subsystems for redundant

protection. If you install only one host subsystem, we recommend that you

install it in slot RE0.

Each host subsystem has three LEDs that display its status. The host subsystem LEDs

are located on the upper right of the craft interface. For more information about the host

subsystem LEDs, see “T640 Craft Interface Host Subsystem LEDs” on page 24.

Documentation

T640 Hardware Component Overview on page 13•

• T640 Routing Engine Description on page 36

• T640 Control Boards Description

• Taking the T640 Host Subsystem Offline on page 307

• Maintaining the T640 Host Subsystem on page 447

T640 Routing Engine Description

The Routing Engine runs Junos OS. The software processes that run on the Routing Engine

maintain the routing tables, manage the routing protocols used on the router, control

the router interfaces, control some chassis components, and provide the interface for

system management and user access to the router.

The T640 router is shipped with Junos OS preinstalled and ready to be configured when

the T640 router is powered on. There are three copies of the software: one on a

CompactFlash card in the Routing Engine, one on a hard disk or solid-state drive in the

Routing Engine, and one on a PC Card or USB storage device that can be inserted into

the slot in the Routing Engine faceplate.

You can install one or two Routing Engines in the router. The Routing Engines install into

the upper rear of the chassis in the slots labeled RE0 and RE1. Each Routing Engine requires

a control board to be installed in the adjacent slot. RE0 installs below CB0, and RE1

installs above CB1. A Routing Engine does not power up without a control board present

in the adjacent slot.

NOTE: If two Routing Engines are installed, they must both be the same

hardware model.

If two Routing Engines are installed, one functions as the master and the other acts as

the backup. If the master Routing Engine fails or is removed, and the backup is configured

appropriately, the backup takes over as the master. If the host system is redundant, the

backup Routing Engine is hot-removable and hot-insertable, but the master Routing

Engine is hot-pluggable. A Routing Engine that is not redundant requires that you power

down the router before replacement.

T640 Core Router Hardware Guide

Juniper T640 Hardware Guide

Other manuals for Juniper T640