Reference Guide

Link Aggregation | 155
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Link Aggregation
The Aggregator auto-configures with link aggregation groups (LAGs) as follows:
• All uplink ports are automatically configured in a single port channel (LAG 128).
• Server-facing LAGs are automatically configured if server NICs are configured for LACP-based NIC
teaming (Network Interface Controller (NIC) Teaming).
No manual configuration is required to configure Aggregator ports in the uplink or a server-facing LAG.
How the LACP is Implemented on an Aggregator
The Link Aggregation Control Protocol (LACP) provides a means for two systems (also called partner
systems) to exchange information through dynamic negotiations to aggregate two or more ports with
common physical characteristics to form a link aggregation group.
A LAG provides both load-sharing and port redundancy across stack units. An Aggregator supports LACP
for the auto-configuration of dynamic LAGs. You can use CLI commands to display LACP information,
clear port-channel counters, and debug LACP operation for auto-configured LAG on an Aggregator.
The FTOS implementation of LACP is based on the standards specified in the IEEE 802.3: "Carrier sense
multiple access with collision detection (CSMA/CD) access method and physical layer specifications."
LACP functions by constantly exchanging custom MAC protocol data unit (PDUs) across LAN Ethernet
links. The protocol packets are only exchanged between ports that are configured as LACP-capable.
Uplink LAG
When the Aggregator powers on, all uplink ports are configured in a single LAG (LAG 128).
Note: Static LAGs are not supported on the Aggregator.
Note: A link aggregation group is referred to as a port channel by the Dell Force10 operating software