User's Manual

Configuration Guide of XGS-5240-Series
124
The port aggregation is that multi-ports are aggregated to form an aggregation group, so
as to implement the out/in load balance in each member port of the aggregation group and
provides the better reliability.
14.2.1 Static LACP Aggregation
Static LACP aggregation is enforced by users configuration, and do not enable LACP
protocol. When configuring static LACP aggregation, use “on” mode to force the port to enter
the aggregation group.
14.2.2 Dynamic LACP Aggregation
1. The summary of the dynamic LACP aggregation
Dynamic LACP aggregation is an aggregation created/deleted by the system
automatically, it does not allow the user to add or delete the member ports of the dynamic
LACP aggregation. The ports which have the same attribute of speed and duplex, are
connected to the same device, have the same basic configuration, can be dynamically
aggregated together. Even if only one port can create the dynamic aggregation, that is the
single port aggregation. In the dynamic aggregation, LACP protocol of the port is at the enable
state.
2. The port state of the dynamic aggregation group
In dynamic aggregation group, the ports have two states: selected or standby. Both
selected ports and standby ports can receive and send LACP protocol, but standby ports can
not forward the data packets.
Because the limitation of the max port number in the aggregation group, if the current
number of the member ports exceeds the limitation of the max port number, then the system of
this end will negotiates with the other end to decide the port state according to the port ID. The
negotiation steps are as follows:
Compare ID of the devices (the priority of the system + the MAC address of the system).
First, compare the priority of the systems, if they are same, then compare the MAC address of
the systems. The end with a small device ID has the high priority.
Compare the ID of the ports (the priority of the port + the ID of the port). For each port in
the side of the device which has the high device priority, first, compare the priority of the ports,
if the priorities are same, then compare the ID of the ports. The port with a small port ID is
selected, and the others become the standby ports.
In an aggregation group, the port which has the smallest port ID and is at the selected
state will be the master port, the other ports at the selected state will be the member port.