EDS-728 Series User’s Manual
Featured Functions
3-14
Using Port Trunking
Link Aggregation allows one or more links to be aggregated together to form a Link Aggregation
Group. A MAC client can treat Link Aggregation Groups as if they were a single link.
The EDS-728’s Port Trunking feature allows devices to communicate by aggregating up to four
links in parallel, with a maximum of eight ports for each link. If one of the eight ports fails, the
other seven ports will provide back up and share the traffic automatically.
Port trunking can be used to combine up to eight ports between two EDS-728 switches. If all ports
on both switch units are configured as 100BASE-TX and they are operating in full duplex, the
potential bandwidth of the connection will be 1600 Mbps.
The Port Trunking Concept
The EDS-728 allows a maximum of 4 trunk groups, with a maximum of 8 trunk ports for each
trunk group. You can configure the trunk group to be “Static” or “LACP.” Once the trunk group is
set to “LACP,” all of the ports making up that group will be set to LACP enabled. The ports in the
“Static” trunk groups, and all the non-trunk ports that do not belong to any trunk group, will be set
to LACP disabled. When the port is set to LACP enabled, it will exchange LACPDU with its link
partner, and will result in “Forwarding.” If all of the ports in the same group are “Blocked” or
“Disabled” or “Down” (link-down), the trunk group will not work, and the user will see “LACP
Failed” for that trunk group in the user interface.
Port Trunking applies to connections between backbone devices as well as to connections in other
network areas where traffic bottlenecks exist. Port Trunking provides the following benefits:
y
Gives you more flexibility in setting up your network connections, since the bandwidth of a
link can be expanded to 8 times the original bandwidth.
y
Load sharing
—
MAC Client traffic may be distributed across multiple links.
Keep the following points in mind when configuring port trunking:
y
To avoid broadcast storms or loops
in your network while configuring a trunk, first disable
or disconnect all ports that you want to add to the trunk or remove from the trunk. After you
finish configuring the trunk, enable or re-connect the ports.
y
Up to 4 port trunking groups
(designated Trk1, Trk2, Trk3, Trk4) can be used for each
EDS-728.
y
Up to 8 ports
can be inserted into each port trunk group. The EDS-728 allows a maximum of
4 “Standby” ports for each LACP trunk group. In another words, a maximum of 12 ports can
belong to each LACP trunk group.
y
The same transmission speed
must be assigned to all ports belonging to one port trunking
group. E.g., 100M Full, 100M Half, 10M Full, or 10M Half. The auto-negotiation function
should be disabled for these ports.
