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RE-MX2000-1800x4 CB-RE Description

 

The RE-MX2000-1800x4 CB-RE runs Junos OS. Software processes that run on the CB-RE 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.

RE-MX2000-1800x4 CB-RE Front Panel

Figure 1 shows the Control Board and Routing Engine (CB-RE)—RE-MX2000-1800x4.

Table 1 describes the Control Board and Routing Engine (CB-RE)—RE-MX2000-1800x4 ports.

Figure 1: RE-MX2000-1800x4 CB-RE Front View
RE-MX2000-1800x4
CB-RE Front View

Table 1: Components on the RE-MX2000-1800x4

Function No.

Label

Description

1

AUX

This port is used to connect a laptop, modem, or other auxiliary unit.

2

CONSOLE

This port is used to configure the MX2000 router.

3

MGMT

This port is a dedicated management channel for device maintenance. It is also used for system administrators to monitor and manage the MX2000 router remotely.

4

USB

This port is used to install a USB flash drive that contains Junos OS.

5

RESET

Reboots the CB-RE.

6

ONLINE/OFFLINE

Takes the Routing Engine on the CB-RE online or offline.

7

LINK

These LEDs are associated with each of the SFP+ ports (XGE-0 and XGE-1) and indicate the connection in use.

8

ExtClk-1 and ExtClk-2

Connects the CB-RE to two external clock interfaces for BITS and GPS function through a serial cable with an RJ-45 connector.

9

GPS, and BITS

There is one bicolor LED for each external clock interface—BITS and GPS.

10

XGE-0 and XGE-1

These ports are used for hardware diagnostics and are for Juniper-internal use only.

11

ONLINE, MASTER, and OK/FAIL

There is one bicolor LED for each CB-RE control. The ONLINE LED indicates that the CB-RE is transitioning online and functioning properly. The MASTER LED indicates that this board is a master Control Board and Routing Engine (CB-RE) , and the OK/FAIL LED indicates the CB-RE has failed.

RE-MX2000-1800x4 CB-RE Components

Each CB-RE consists of the following components:

  • External clock interface—Allows BITS or GPS clock source input to the centralized timing circuit, or allows centralized timing to be output to BITS or GPS.

  • 1000Base-T Ethernet controller

  • Circuits for chassis management and control.

  • Power circuits for the CB-RE.

  • Control FPGA—Provides the Peripheral Component Interconnect (PCI) interface to the routing engine.

  • Gigabit Ethernet switch that is connected to the embedded CPU complex on all components.

  • CPU—Runs Junos OS to maintain the router's routing tables and routing protocols.

  • I2C bus logic, used for low-level communication with each component.

  • DRAM—Provides storage for the routing and forwarding tables and for other routing engine processes.

  • Component redundancy circuitry.

  • USB port—Provides a removable media interface through which you can install the Junos OS manually. Junos OS supports USB version 1.0.

  • CompactFlash card—Provides primary storage for software images, configuration files, and microcode. The CompactFlash card is fixed and is inaccessible from outside the router.

  • Solid State Disk (non-removable)—Provides secondary storage for log files, memory dumps, and rebooting the system if the CompactFlash card fails.

  • Interface ports—The AUX, CONSOLE, and MGMT ports provide access to management devices. Each CB-RE has one 10/100-Mbps Ethernet port for connecting to a management network, and two asynchronous serial ports—one for connecting to a console and one for connecting to a modem or other auxiliary device. The two ports labeled XGE-0 and XGE-1 are used for hardware diagnostics and are for Juniper-internal use only. The ExtClk ports provide access to external timing distribution.

  • EEPROM—Stores the serial number of the CB-RE.

  • Reset button—Reboots the Routing Engine on the CB-RE when pressed.

  • Online/Offline button—Takes the Routing Engine on the CB-RE online or offline when pressed.

  • LEDs—Provide status of the Routing Engine on the CB-RE.

RE-MX2000-1800x4 CB-RE Software

The RE-MX2000-1800x4 CB-RE runs Junos OS. Software processes that run on the CB-RE 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.

RE-MX2000-1800x4 CB-RE Boot Sequence

The router is shipped with the Junos OS pre-installed on the CB-RE. There are three copies of software:

  • One copy on a USB flash drive that can be inserted into the slot on the CB-RE faceplate.

  • One copy on the CompactFlash card in the Routing Engine.

  • One copy on the Solid State Disk (SSD) in the CB-RE.

    Note

    The SSD is internal and cannot be removed.

The Routing Engine interface boots from the storage media in this order: the USB device (if present), then the CompactFlash card, then the SSD, and then the LAN. Normally, the router boots from the copy of the software on the CompactFlash card.