Routing Engine; Routing Engine Components - Juniper MX240 Hardware Manual

MX240 Ethernet Services Router Hardware Guide

Routing Engine

The Routing Engine is an Intel-based PC platform that runs JUNOS software. 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.
You can install one or two Routing Engines in the router. The Routing Engines install
into the front of the chassis in horizontal slots in the SCBs labeled
Routing Engine must be installed directly into an SCB. A USB port on the Routing
Engine accepts a USB memory card that allows you to load JUNOS software.
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. The Backup Routing
Engine is hot-insertable and hot-removable.
The MX240 router supports the RE-S-1300-2048 Routing Engine and the
RE-S-2000-4096 Routing Engine. Both Routing Engines have the same ports and
LEDs on the faceplate.
NOTE: If two Routing Engines are installed, they must both be the same hardware
version.
Figure 9: Routing Engine

Routing Engine Components

Each Routing Engine (shown in Figure 9 on page 14) consists of the following
components:
14
Host Subsystem
0 and 1/0 . Each