Introduction To Link Aggregation; Link Aggregation Supported By The Ar3200 - Huawei AR3200 Series Configuration Manual - Lan

Huawei AR3200 Series Enterprise Routers
Configuration Guide - LAN

1.1 Introduction to Link Aggregation

This section describes the concept of link aggregation.
Link aggregation refers to a method of bundling a group of physical interfaces into a logical
interface to increase bandwidth and improve reliability. These types of groupings are also called
multi-interface load sharing groups or link aggregation groups (LAGs). For details, refer to
IEEE802.3ad.
Link aggregation provides redundancy protection for communication channels among between
devices without upgrading the hardware to higher capacities.

1.2 Link Aggregation Supported by the AR3200

This section describes the link aggregation features supported by the AR3200.
Manual Load Balancing Mode
In load balancing mode, you can manually add member interfaces to a link aggregation group
(LAG). All the interfaces configured with load balancing are in forwarding state. The AR3200
can perform load balancing based on destination MAC addresses, source MAC addresses,
Exclusive-Or of source and destination MAC addresses, source IP addresses, destination IP
addresses, or Exclusive-Or of source and destination IP addresses.
The manual load balancing mode does not use the Link Aggregation Control Protocol (LACP).
The AR3200 can use this mode if the peer device does not support LACP.
Static LACP Mode
In static LACP mode, devices at two ends of a link negotiate aggregation parameters by
exchanging LACP packets. After the negotiation is complete, the two devices determine the
active interface and the inactive interface. In this mode, you need to manually create an Eth-
Trunk and add members to it. LACP negotiation determines which interfaces are active and
which ones are inactive.
The static LACP mode is also called the M:N mode. In this mode, links load balance traffic and
provide redundancy backup at the same time. In an LAG, M links are active and they forward
data in load balancing mode. N links are inactive and they function as backup links. The backup
links do not forward data. If an active link fails, data forwarding is switched to the backup link
with the highest priority, and the status of the backup link changes to active.
In static LACP mode, some links function as backup links. In manual load balancing mode, all
member interfaces work in forwarding state to share the traffic. This is the main difference
between the two modes.
Active and Inactive Interfaces
Active interfaces refer to the interfaces in active state that forward data. The interfaces that do
not forward data and are in inactive state are called inactive interfaces. Depending on the link
aggregation mode the interfaces use, active and inactive interfaces are classified as follows:
Issue 02 (2012-03-30) Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
1 Link Aggregation Configuration
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