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    MX2020 Enhanced Switch Fabric Board (SFB2) Description

    Figure 1: SFB2


    Software release

    • Junos OS Release 15.1F5 and later
    • Name in CLI: Switch Fabric Board


    The MX2000 Enhanced Switch Fabric Board (SFB2; model number: MX2000-SFB2-S) provides increased fabric bandwidth per slot. MX2000 line of routers can support eight Switch Fabric Boards (SFB) and eight Enhanced Switch Fabric Boards (SFB2) but not both at the same time. The SFB2 is supported on MX2010 and MX2020 routers. Refer to Figure 1.

    Note: During an upgrade from SFB to SFB2, the MX2000 line of routers support both SFB and SFB2 at the same time for the duration of the upgrade.

    SFB2 Features and Components

    • PCIe control of two XF ASICs
    • I2C bus logic interface, used for component management and monitoring of temperature, and voltage
    • Switch fabric—Provides switching functions for the MPCs
    • Fabric capacity—Supports 1600 Gbps per slot with eight SFB2, and 1600 Gbps per slot with seven SFB2.
    • Circuits for chassis management and control
    • Power circuits for the SFB2
    • LED—Provides status of the SFB2

    SFB2 Slots

    You can install up to eight SFB2s in the MX2000 router. The SFB2s 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.

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

    SFB2 Redundancy

    Seven of eight SFB2s are required for line rate operation. The system can continue operating with fewer than seven SFB2s, but forwarding performance will be impacted.

    Weight and Dimensions

    • Weight: 12 lb (5.44 kg)
    • Width: 1.7 in. (4.31 cm)
    • Depth: 23.6 in. (59.94 cm). With ejector handle: 26.14 in. (66.39 cm)
    • Height: 16.225 in. (41.21 cm)

    Maximum Power Requirements (without MICs)


    • Typical: 250 W
    • At different temperatures:

      295 W at 55° C

      280 W at 40° C

      270 W at 25° C


    • Typical: 220 W
    • At different temperatures:

      265 W at 55° C

      250 W at 40° C

      240 W at 25° C


    OK/FAIL LED, one bicolor:

    • Steady green—SFB2 is online and functioning normally.
    • Slow blinking green—SFB2 is initializing.
    • Fast blinking green—SFB2 is being identified by software.

      Note: This is used to guide the operator to correct any action needed on the SFB2.

    • Red—SFB2 has failed.
    • Off—SFB2 is offline.

    Each SFB2 also has a set of bicolor LEDs on the craft interface that indicate its status. The SFB2 LEDs, labeled 0 through 7, are located along the bottom center of the craft interface. For more information about the SFB2 LED on the craft interface, see MX2020 Component LEDs on the Craft Interface and MX2010 Component LEDs on the Craft Interface.

    Modified: 2017-02-09