546 | Link Aggregation Control Protocolw w w . d e l l . c o m | s u p p o r t . d e l l . c o m Figure 24-4. Invoking the LACP Long TimeoutMonitor and Debugging LACPThe system log (syslog) records faulty LACP actions.To debug LACP, use the following command:Shared LAG State TrackingShared LAG State Tracking provides the flexibility to bring down a port channel (LAG) based on theoperational 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.In Figure 24-5, line-rate traffic from R1 destined for R4 follows the lowest-cost route via R2, as shown.Traffic is equally distributed between LAGs 1 and 2. If LAG 1 fails, all traffic from R1 to R4 flows acrossLAG 2 only. This condition over-subscribes the link, and packets are dropped.Note: View PDU exchanges and the timeout value using the command debug lacp. See Monitor andDebugging LACP on page 546.Command Syntax Command Mode Purpose[no] debug lacp [config | events | pdu[in | out | [interface [in | out]]]]EXEC Debug LACP, including configuration and events.FTOS(conf)# interface port-channel 32FTOS(conf-if-po-32)#no shutdownFTOS(conf-if-po-32)#switchportFTOS(conf-if-po-32)#lacp long-timeoutFTOS(conf-if-po-32)#endFTOS# show lacp 32Port-channel 32 admin up, oper up, mode lacpActor System ID: Priority 32768, Address 0001.e800.a12bPartner System ID: Priority 32768, Address 0001.e801.45a5Actor Admin Key 1, Oper Key 1, Partner Oper Key 1LACP LAG 1 is an aggregatable linkA - Active LACP, B - Passive LACP, C - Short Timeout, D - Long TimeoutE - Aggregatable Link, F - Individual Link, G - IN_SYNC, H - OUT_OF_SYNCI - Collection enabled, J - Collection disabled, K - Distribution enabled L - Distribution disabled,M - Partner Defaulted, N - Partner Non-defaulted, O - Receiver is in expired state,P - Receiver is not in expired statePort Gi 10/6 is enabled, LACP is enabled and mode is lacpActor Admin: State ADEHJLMP Key 1 Priority 128
