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Control Board in a QFX3008-I Interconnect Device


The Control Board performs Routing Engine functions in a QFX3008 Interconnect device. See Figure 1.

The Control Boards install horizontally into the top rear of the chassis in slots labeled CB 0 and CB 1.

Figure 1: Control Board in a QFXC08 Chassis
Control Board in a QFXC08

One Control Board functions as the master, and the other acts as the backup. If the master Control Board fails or is removed, the backup Control Board takes over as the master Control Board. When the Control Boards are configured for graceful switchover, the backup Control Board automatically synchronizes its configuration and state with those of the master Control Board. Any update to the master Control Board is replicated on the backup Control Board. If the master Control Board fails, or mastership is switched to the backup Control Board, packet forwarding stops on the QFXC08 chassis. When the backup Control Board assumes mastership, packet forwarding continues through the device.

If you need to replace the master Control Board, we recommend that you switch mastership to the backup Control Board. We recommend that you always take a Control Board offline before removing it. See Taking a Control Board Offline in a QFX3008-I Interconnect Device.

The Control Board provides these functions:

  • Powers the 16-port QSFP+ front cards on and off

  • Powers the rear cards on and off

  • Performs routing functions for the device

  • Controls system resets and the boot sequence for the device

  • Monitors and controls the speed of the fans in the fan trays

  • Monitors and controls the LCD panel and chassis status LEDs

  • Monitors the communication of the 16-port QSFP+ front cards with the rear cards

  • Monitors the status of the power supplies

The Control Board has these components: