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MX2008 Switch Fabric Boards

MX2008 Enhanced Switch Fabric Board (MX2008 SFB2) Description

The MX2008 Enhanced Switch Fabric Board (MX2008 SFB2; model number: MX2008-SFB2) connects to the signal backplane (see Figure 1). The MX2008 SFB2 and the native MX2000 SFB2 are exactly the same except that the native MX2000 SFB2 has two PF fabric chips per card whereas MX2008 SFB2 has only one PF fabric chip per card, and that MX2008 SFB2 is less than half the size of the native MX2000 SFB2.

Figure 1: MX2008 SFB2MX2008 SFB2

OK/FAIL LED showing the SFB2 status


MX2008 SFB2 Slots

You can install up to eight SFB2 boards in the MX2008 router. The MX2008 SFB2 boards install vertically into the front of the chassis in the slots labeled 0 through 7. If any slots are empty, you must install a blank panel.


If one of the MX2008 SFB2s fails, do not remove the failed SFB2 until you have a replacement or blank panel to install.

MX2008 SFB2 Redundancy

Seven out of eight MX2008 SFB2 boards are required for line-rate operation. The system can continue operating with fewer than seven SFB2s, but forwarding performance is impacted.

MX2008 SFB2 Components

Each MX2008 SFB2 consists of the following components:

  • One PF fabric chip per card

  • PCIe control of one PF ASIC

  • I2C bus logic interface, used for component management and monitoring of temperature, and voltage

  • Switch fabric—Provides the switching functions for the MPCs

  • Fabric capacity—MX2008 SFB2 supports 2000 Gbps per slot throughput without redundancy

  • Circuits for chassis management and control

  • Power circuits for the MX2008 SFB2

  • LED—Provides status of the MX2008 SFB2


One bicolor LED on the MX2008 SFB2 indicates the status of the SFB. The LED, labeled OK/FAIL, is located directly on the SFB. Table 1 describes the functions of the MX2008 SFB2 LED.

Figure 2: MX2008 SFB2 LEDMX2008 SFB2 LED
Table 1: MX2008 Switch Fabric Board LED

Function No.








Slow blinking when being initialized.

Fast blinking when SFB is being identified by software.


The blinking of the LED is used to guide the operator to correct any action needed on the SFB.

SFB is online.


On steadily

SFB has failed.


SFB is offline.

Each SFB also has a set of bicolor LEDs on the craft interface that indicate its status. The SFB LED, labeled 0 through 7, are located along the bottom center of the craft interface. For more information about the SFB LEDs on the craft interface, see MX2008 Component LEDs on the Craft Interface.