Configuring Breakout Ports and Sub-Ports

You can configure breakout ports at the global configuration mode. After successful configuration and activation of breakout, the sub-ports are available for configuration. By default, all main 40 Gbps ports are configured to come up in 40 Gbps mode.
  1. Enter the global configuration mode.
    device# configure terminal
  2. Configure breakout port.
    device(config)# breakout ethernet 1/1/11
device# write memory
device# reload

    The breakout ethernet command divides the ports into sub-ports when a breakout cable is attached.

    The breakout ethernet command first checks the existing configuration on the port. If existing configuration is detected, an error message is displayed to indicate that the prior configuration must be removed. Then the breakout ethernet command must be re-issued and the resulting configuration must be saved and reloaded before the four 10 Gbps sub-ports are created.

    Note: If the ICX 7750 device is in cut-through mode and you attempt to configure breakout, an error is returned. Cut-through must be disabled to return the unit to store-and-forward mode before breakout is configured. However, ICX 7850 does not need to be in store-and-forward mode for breakout to be functional.
  3. Configure sub-ports.
    device(config)#interface ethernet 1/1/11:1 to 1/1/11:4
    In the example, port 1/1/11 has been configured for breakout into four 25 Gbps sub-ports. Sub-ports are denoted by special four-tuple notation to indicate unit, slot, port, and sub-port.
    Note: Once breakout is removed and the device is reloaded, the sub-ports and their configuration are also removed.

The following example shows how to configure breakout on Ethernet port, 1/1/11.

device# configure terminal
device(config)# breakout ethernet 1/1/11
device# write memory
device# reload
device(config)#interface ethernet 1/1/11:1 to 1/1/11:4
Parent topic: Overview of Breakout Ports