EX2500 Ethernet Switch Configuration Guide
NOTE: LACP implementation in the EX2500 switch does not support the Churn machine, an option used to detect if the port is operable within a bounded time period between the actor and the partner. Only the Marker Responder is implemented, and there is no marker protocol generator.
A port’s Link Aggregation Identifier (LAG ID) determines how the port can be aggregated. The Link Aggregation ID (LAG ID) is constructed mainly from the system ID and the port’s admin key, as follows:
System
Admin
For example, consider two switches, an Actor (the EX2500 switch) and a Partner (another switch), as shown in Table 11.
Table 11: Actor vs. Partner LACP Configuration
Actor Switch | Partner Switch 1 |
|
|
Port 7 (admin key = 100) | Port 1 (admin key = 50) |
|
|
Port 8 (admin key = 100) | Port 2 (admin key = 50) |
|
|
In the configuration shown in Table 11, Actor switch port 7 and port 8 aggregate to form an LACP trunk group with Partner switch port 1 and port 2.
LACP automatically determines which member links can be aggregated and then aggregates them. It provides for the controlled addition and removal of physical links for the link aggregation.
Each port on the switch can have one of the following LACP modes:
off
Each active LACP port transmits LACP data units (LACPDUs), while each passive LACP port listens for LACPDUs. During LACP negotiation, the admin key is exchanged. The LACP trunk group is enabled as long as the information matches at both ends of the link. If the admin key value changes for a port at either end of the link, that port’s association with the LACP trunk group is lost.
