Approaches To Link Aggregation; Manual Link Aggregation - H3C S7500E Series Operation Manual

Operation Manual – Link Aggregation
H3C S7500E Series Ethernet Switches

1.2 Approaches to Link Aggregation

Two ways are available for implementing link aggregation, as described in
Aggregation

1.2.1 Manual Link Aggregation

I. Overview
Manual aggregations are created manually. Member ports in a manual aggregation are
LACP-disabled.
II. Port states in a manual aggregation
In a manual aggregation group, ports are either selected or unselected. Selected ports
can receive and transmit data frames whereas unselected ones cannot.
When setting the state of ports in a manual aggregation group, the system considers
the following:
The system selects the port with the highest priority in the up state as the
reference port of the aggregation group. Port priority descends in the following
order: full duplex/high speed, full duplex/low speed, half duplex/high speed, and
half duplex/low speed. If multiple ports are of the same priority, the one with the
lowest port number is the reference port.
Ports in the up state with the same speed, duplex mode, link state, and basic
configuration as the reference port become the candidates for selected ports,
while the other ports become unselected ports.
There is a limit on the number of selected ports in a manual aggregation group. If
the number of selected-port candidates does not reach the limit, all the candidates
become selected ports; if the number of candidates exceeds the limit, the
candidates with lower port numbers become selected ports, while the other
candidates become unselected ports.
The selected port with the lowest port number serves as the master port of the
aggregation group, and the other ports serve as the member ports of the
aggregation group.
If all the ports of an aggregations port are down, the port with the lowest port
number is the master port. In this case, all of them are unselected ports.
In addition, unless the master port should be selected, a port that joins the group after
the limit is reached will not be placed in selected state even if it should be in normal
cases. This is to prevent the ongoing service on selected ports from being interrupted.
You need to avoid the situation however as the selected/unselected state of a port may
become different after a reboot.
and Static LACP link aggregation.
Chapter 1 Link Aggregation Overview
1-3
Manual Link