Breakout

Feature Overview

The Breakout feature allows certain 40-Gbps ports on ICX 7550 and ICX 7850 standalone units, as well as ICX 7850 stacking configurations, to be divided into four 10-Gbps subports using a breakout cable. Additionally, 100-Gbps ports can be divided into four 25-Gbps subports. This enhances port flexibility and density, providing more options for network configuration.

Dynamic Breakout allows breakout configurations to be applied without requiring a device reload. This means users can enable or disable breakout modes dynamically, enhancing operational efficiency and reducing downtime. The dynamic breakout feature also supports configuring individual subports to run at different speeds (e.g., 1G, 10G, or 25G), providing even greater flexibility in network management.

Requirements

  • Breakout is supported for RUCKUS ICX 7550 and ICX 7850 devices.
  • For ICX 7550 devices, breakout is supported for standalone units.
  • For ICX 7850 devices, breakout is supported for standalone units and stacking configurations.
  • A breakout cable is required for configuring breakout ports. Refer to the RUCKUS ICX 7550 Switch Hardware Installation Guide and RUCKUS ICX 7850 Ethernet Switch Hardware Installation Guide for detailed information on breakout cables.

Considerations

  • From 10.0.20b_cd1, dynamic breakout is supported so that a reload is not required once dynamic breakout is enabled.
  • In a stacking setup, a downgrade from a dynamic breakout configuration to a non-dynamic breakout version is not supported. However, in standalone mode, downgrading from a dynamic breakout to any non-dynamic breakout configuration is supported.
  • For ICX 7550 devices, breakout ports can only be configured when stacking is not enabled.
  • For ICX 7550-24ZP, ICX 7550-24F, and ICX 7550-24XZP devices, the uplink-40-Gbps mode supports only 2x40-Gbps in module 3 and an error message is displayed if an unsupported module is present in module 3.
  • For ICX 7550-24ZP, ICX 7550-24F, and ICX 7550-24XZP devices, the breakout configuration must be removed before disabling the module 2 40/100-Gbps uplink mode by running the no slot 2 uplink-40g or the no slot 2 uplink-100g command.
  • For ICX 7550-48ZP and ICX 7550-48F devices, the uplink-40-Gbps mode is supported only if module 3 contains a 2x40-Gbps configuration or if module 3 is empty.
  • Breakout configurations are not dynamically re-evaluated when optics are inserted after a reboot or reseated during runtime. For example, if a port is configured for 4x25G breakout and the device is rebooted without optics, inserting 4x10G optics afterward does not trigger a reconfiguration. The ports remain down due to a mismatch between the configured breakout speed and the inserted optic type. This behavior also applies to optic reseat scenarios (plug-in/plug-out). Inserting a different optic type into a breakout-configured port, even during runtime, does not result in automatic re-evaluation or reconfiguration of the breakout settings. To avoid this issue:
    • Ensure the correct optics are inserted before rebooting the device.
    • If a different optic type is required after reboot or optic reseat, manually remove and reconfigure the breakout settings to match the new optic type.
    • To change from one optic type to another (e.g., from 4x10G to 4x25G), first unconfigure the existing breakout settings, then reconfigure them to match the new optic type.

Downgrade Considerations for Breakout with Stacking Enabled

From 10.0.20b_cd1 and later, stacking with breakout is supported on ICX 7850 devices. However, downgrading from 10.0.20b_cd1 to a pre-10.0.20b_cd1 release while both stacking and breakout configurations are enabled will break the stack.

If you are downgrading to a release that does not support both stacking and breakout configurations, consider the following options:

Option 1: Downgrade with a Confirmation Warning

When using one of the following commands:

  • reload
  • boot system flash primary
  • boot system flash secondary

The system prompts you with a warning before proceeding:

ICX7850-48F Router# reload
(enter 'y' or 'n'): y

The startup config has both breakout and stack enable. You are downgrading to a release that does not support both. Reloading will break the stack. To avoid this, you can remove all breakout and do "wr mem" before reloading.

Do you want to reload? (enter 'y' or 'n'): n

If you select "n" (no), the reload is canceled, allowing you to remove the breakout configuration before proceeding.

Option 2: Force Downgrade without Confirmation

When using one of the following commands:

  • boot system flash primary yes
  • boot system flash secondary yes
  • reload-yes

The system does not display a warning or request confirmation. The entire stack reloads immediately, and the stack breaks because stacking is disabled due to the existing breakout configuration.

Perform the following steps if the stack breaks after downgrading because the breakout configuration was not removed:

  1. Remove the breakout configuration. Refer to Removing Breakout Configuration for more information.
  2. Re-enable stacking using the stack enable command. Refer to the RUCKUS FastIron Command Reference for more information.
  3. Save the configuration using the write memory command. Refer to the RUCKUS FastIron Command Reference for more information.

If the stack still does not form, use the stack interactive-setup option 3 command to rebuild the stack.

Before removing a breakout configuration, you may need to first remove any associated configurations, such as LAG membership, keep-alive settings, or DHCPv6. When you attempt to remove a breakout using the no breakout ethernet command, the system displays any existing associations. If no associations exist, the breakout configuration is removed successfully.

The following example demonstrates the need to remove associated configurations before proceeding with breakout removal:

device(config-if-e25000-1/2/3:4)# no breakout e 1/2/3
Stack port e 1/2/3:3 has config: "no dhcp6 snooping relay information"
Stack port e 1/2/3:4 has config: "no dhcp6 snooping relay information"

To resolve this, remove the associated configurations:

device(config)# interface ethernet 1/2/3:3
device(config-if-e25000-1/2/3:3)# dhcp6 snooping relay information
device(config-if-e25000-1/2/3:3)# interface ethernet 1/2/3:4
device(config-if-e25000-1/2/3:4)# dhcp6 snooping relay information

After removing the associations, you can successfully remove the breakout configuration, save the configuration, and enable stacking if needed.

Best Practices

  • Remove all breakout configurations and enter write memory before downgrading.
  • Before configuring breakout ports, ensure that there are no existing configurations on the ports. Use the show running-config interface command to verify the current port configuration. Refer to the RUCKUS FastIron Command Reference for more information.
  • Before making any changes, always back up the current configuration. This ensures you can quickly restore the previous state if needed.
  • Before configuring breakout ports, verify if the slot 2 uplink-40g or slot 2 uplink-100g commands are required for your configuration.
  • Clearly label the breakout ports to avoid confusion during troubleshooting and maintenance. This helps to quickly identify the correct ports.
  • Use appropriate breakout cables and ensure effective cable management to prevent physical damage and maintain signal integrity.
  • Always verify that connectors are properly inserted to prevent connectivity issues and potential damage to the ports.

Prerequisites

  • Any existing interface-level configuration must be removed before configuring dynamic breakout.
  • The RUCKUS ICX 7550-24ZP, ICX 7550-48ZP, ICX 7550-24F, and ICX 7550-48F models require configuring the slot 2 uplink-40g or slot 2 uplink-100g command before configuring breakout.
  • The RUCKUS ICX 7550-24ZP, ICX 7550-24XZP, ICX7550-24XZP and ICX 7550-24F models require configuring the slot 2 uplink-40g or slot 2 uplink-100g command before applying the breakout on ports 1/2/1 and 1/2/2, and then reloading to take effect. The slot 2 operates in uplink mode with 40/100 Gbps as per uplink configuration speed after the reload.

In this section:

  1. Ports Available for Breakout
  2. Configuring Breakout Ports and Subports
    The breakout functionality is disabled by default and can be enabled. After successful configuration and activation of breakout, the subports are available for configuration.
  3. Displaying Information for Breakout Ports
    You can use the show breakout command output to display information for breakout port status.
  4. Setting Module 2 to Uplink-100-Gbps Mode
  5. Setting Module 2 to 40G Uplink Mode
  6. Removing Breakout Configuration
    Use the no breakout ethernet command to remove the breakout configuration.
  7. 1G Breakout Subports
    The four 4x10-Gbps breakout subports derived from a 40G module can be configured to 1 Gbps separately, so that the subports do not need to be configured at the same speed.
  8. Configuring 1G Breakout Ports
    The following example configures a breakout subport and changes the breakout port speed to 1-Gbps. No reload is required for the new subport speed to take effect.
Parent topic: Configuration Fundamentals