Dynamic Link Aggregation Overview
Configuring Dynamic Link Aggregation
page 8-6
OmniSwitch AOS Release 7 Network Configuration Guide
June 2013
An example of what these commands look like entered sequentially on the command line on the partner
switch:
-> linkagg lacp agg 2 size 8 actor admin-key 5
-> linkagg lacp port 2/1 actor admin-key 5
-> linkagg lacp port 3/1 actor admin-key 5
-> linkagg lacp port 3/3 actor admin-key 5
-> linkagg lacp port 3/6 actor admin-key 5
-> linkagg lacp port 5/1 actor admin-key 5
-> linkagg lacp port 5/6 actor admin-key 5
-> linkagg lacp port 8/1 actor admin-key 5
-> linkagg lacp port 8/3 actor admin-key 5
-> vlan 2 port default 2
Dynamic Link Aggregation Overview
Link aggregation allows you to combine 2, 4, or 8 physical connections into large virtual connections
known as link aggregation
groups
. You can configure up to 128 link aggregation groups for the switch and
up to 128 groups for a chassis-based switch. Each group can consist of 2, 4, or 8 Ethernet links.
You can create Virtual LANs (VLANs), 802.1Q framing, configure Quality of Service (QoS) conditions,
and other networking features on link aggregation groups because switch software treats these virtual links
just like physical links. (See
“Relationship to Other Features” on page 8-8
for more information on how
link aggregation interacts with other software features.)
Link aggregation groups are identified by unique MAC addresses, which are created by the switch but can
be modified by the user at any time. Load balancing for Layer 2 non-IP packets is on a MAC address basis
and for IP packets the balancing algorithm uses the IP address as well. Ports
must
be of the same speed
within the same aggregate group.
Alcatel-Lucent’s link aggregation software allows you to configure the following
two different types of
link aggregation groups:
•
Static link aggregate groups
•
Dynamic link aggregate groups
This chapter describes dynamic link aggregation. For information on static link aggregation, please refer to
Chapter 7, “Configuring Static Link Aggregation.”
Dynamic Link Aggregation Operation
Dynamic aggregate groups are virtual links between two nodes consisting of 2, 4, or 8 10-Mbps,
100-Mbps, or 1-or 10-Gbps fixed physical links. Dynamic aggregate groups use the standard IEEE
802.3ad Link Aggregation Control Protocol (LACP) to dynamically establish the best possible
configuration for the group. This task is accomplished by special Link Aggregation Control Protocol Data
Unit (LACPDU) frames that are sent and received by switches on both sides of the link to monitor and
maintain the dynamic aggregate group.
The figure on the following page shows a dynamic aggregate group that has been configured between
Switch A and Switch B. The dynamic aggregate group links four ports on Switch A to four ports on
Switch B.