You can configure priorities, keys, modes, and timers for the LACP.
You can configure LACP priority at the system and port level as follows:
Port priority—determines which ports are aggregated into a LAG that has more than eight ports configured to it.
System priority—generates the switch ID after communicating with other systems. As a best practice, use the default value. If you need to change it, first disable the LACP, and then enable it again after you change the value.
You must use the LACP keys to determine which ports are eligible for link aggregation. The LACP keys are defined by the ports after you configure the multilink trunk. You can aggregate the ports key that match the MLT key into that multilink trunk.
Keys do not have to match between two LACP peers.
You can customize failover times by changing the LACP timer attributes (fast periodic time, slow periodic time, and aggregate wait time). Values are set by default to match the IEEE 802.3ad values. If you change the values, they must match on the ports participating in aggregation between two devices.
Changes to LACP timer values at the global level are reflected on all ports. However, you can change the LACP timer values for each port level. After you change an LACP timer globally, this value is set on all ports. The global timer value overwrites the local port value irrespective of the LACP state. You must configure port values that differ from the global values.
The switch software uses the following LACP timers:
fast periodic timer—200 to 20 000 milliseconds (ms); default 1000 ms
slow periodic timer—10 000 to 30 000 ms; default 30000 ms
aggregation-wait timer—200 to 2000; default 2000
You cannot aggregate a link if it does not receive an LACPDU for a period of timeout x slow periodic time = 3 x 30 seconds = 90 seconds. If you use the fast periodic time, the timeout period is 3 x 1000 ms = 3 seconds. You must make timer changes to all ports participating in link aggregation and to the ports on the partnering node.
Configuration changes to the LACP timers are not reflected immediately. Link Aggregation Control Protocol timers do not reset until the next time you restart LACP globally or on a port. This ensures consistency with peer switches.
After you enable LACP on a port, the timer values are set at the port level. You must toggle the LACP status after timer values change. This does not impact existing ports unless you toggle the LACP status on the port.
LACP uses two active and passive modes.
Active mode—ports initiate the aggregation process. Active mode ports aggregate with other active mode ports or passive mode ports.
Passive mode—ports participate in LACP but do not initiate the aggregation process. You must partner passive mode ports with active mode ports for aggregation to occur.
When using LACP, configure the private-vlan at the interface level.
For the latest applicable scaling information, see VSP 8600 Release Notes for the version of the software running on the switch.