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Example: Configuring Link Aggregation Control Protocol on a Security Device (CLI Procedure)


This example shows how to configure LACP.


This example uses an SRX Series device.

Before you begin:

  • Determine which interfaces to use and verify that they are in switch mode. See Understanding VLANs.


In this example, for aggregated Ethernet interfaces, you configure the Link Aggregation Control Protocol (LACP). LACP is one method of bundling several physical interfaces to form one logical interface.


CLI Quick Configuration

To quickly configure this section of the example, copy the following commands, paste them into a text file, remove any line breaks, change any details necessary to match your network configuration, copy and paste the commands into the CLI at the [edit] hierarchy level, and then enter commit from configuration mode.

Step-by-Step Procedure

The following example requires you to navigate various levels in the configuration hierarchy. For instructions on how to do that, see Using the CLI Editor in Configuration Mode in the CLI User Guide.

To configure LACP:

  1. Configure the interfaces for ae0.
  2. Configure ae0 interface for vlan tagging.
  3. Configure LACP for ae0 and configure periodic transmission of LACP packets.
  4. Configure ae0 as a trunk port.
  5. Configure the VLAN.
  6. Add the ae0 interface to the VLAN.
  7. If you are done configuring the device, commit the configuration.


From configuration mode, confirm your configuration by entering the show interfaces command. If the output does not display the intended configuration, repeat the configuration instructions in this example to correct it.


Verifying LACP Statistics


Display LACP statistics for aggregated Ethernet interfaces.


From operational mode, enter the show lacp statistics interfaces ae0 command.

user@host> show lacp statistics interfaces ae0


The output shows LACP statistics for each physical interface associated with the aggregated Ethernet interface, such as the following:

  • The LACP received counter that increments for each normal hello packet received

  • The number of LACP transmit packet errors logged

  • The number of unrecognized packet errors logged

  • The number of invalid packets received

Use the following command to clear the statistics and see only new changes:

Verifying LACP Aggregated Ethernet Interfaces


Display LACP status information for aggregated Ethernet interfaces.


From operational mode, enter the show lacp interfaces ae0 command.

user@host> show lacp interfaces ae0


The output shows aggregated Ethernet interface information, including the following information:

  • The LACP state—Indicates whether the link in the bundle is an actor (local or near-end of the link) or a partner (remote or far-end of the link).

  • The LACP mode—Indicates whether both ends of the aggregated Ethernet interface are enabled (active or passive)—at least one end of the bundle must be active.

  • The periodic link aggregation control PDU transmit rate.

  • The LACP protocol state—Indicates the link is up if it is collecting and distributing packets.