ES-4024A User’s Guide
Chapter 15 Link Aggregation 107
CHAPTER 15
Link Aggregation
This chapter shows you how to logically aggregate physical links to form one logical, higher-
bandwidth link.
15.1 Overview
Link aggregation (trunking) is the grouping of physical ports into one logical higher-capacity
link. You may want to trunk ports if for example, it is cheaper to use multiple lower-speed
links than to under-utilize a high-speed, but more costly, single-port link.
However, the more ports you aggregate then the fewer available ports you have. A trunk group
is one logical link containing multiple ports.
The beginning port of each trunk group must be physically connected to form a trunk group.
Ports should be physically linked in consecutive order without gaps when forming trunk
groups.
15.1.1 Dynamic Link Aggregation
The ES-4024A adheres to the IEEE 802.3ad standard for static and dynamic (LACP) port
trunking.
The ES-4024A supports the link aggregation IEEE802.3ad standard. This standard describes
the Link Aggregate Control Protocol (LACP), which is a protocol that dynamically creates and
manages trunk groups.
When you enable LACP link aggregation on a port, the port can automatically negotiate with
the ports at the remote end of a link to establish trunk groups. LACP also allows port
redundancy, that is, if an operational port fails, then one of the “standby” ports become
operational without user intervention. Please note that:
Table 27 Trunk Groups
TRUNK GROUP BEGINNING PORT PORT RANGE
1 1 1 to 8
2 9 9 to 16
3 17 17 to 24
4 25 25 and 26 (the mini GBIC ports)
5 S1 S1 and S2 (the stacking ports)
