Setup Guide

1 second. You can congure the default timeout value to be 30 seconds. Invoking the longer timeout might prevent the LAG from apping

if the remote system is up but temporarily unable to transmit PDUs due to a system interruption.

NOTE: The 30-second timeout is available for dynamic LAG interfaces only. You can enter the lacp long-timeout command

for static LAGs, but it has no eect.

To congure LACP long timeout, use the following command.

• Set the LACP timeout value to 30 seconds.

CONFIG-INT-PO mode

lacp long-timeout

Example of the lacp long-timeout and show lacp Commands

To view the PDU exchanges and the timeout value, use the debug lacp command. For more information, refer to Monitoring and

Debugging LACP.

Monitoring and Debugging LACP

The system log (syslog) records faulty LACP actions.

To debug LACP, use the following command.

• Debug LACP, including conguration and events.

EXEC mode

Shared LAG State Tracking

Shared LAG state tracking provides the exibility to bring down a port channel (LAG) based on the operational state of another LAG.

At any time, only two LAGs can be a part of a group such that the fate (status) of one LAG depends on the other LAG.

As shown in the following illustration, the line-rate trac from R1 destined for R4 follows the lowest-cost route via R2. Trac is equally

distributed between LAGs 1 and 2. If LAG 1 fails, all trac from R1 to R4 ows across LAG 2 only. This condition over-subscribes the link

and packets are dropped.

Figure 61. Shared LAG State Tracking

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Link Aggregation Control Protocol (LACP)