Link Aggregation - D-Link DES-3326SR User Manual

DES-3326SR Layer 3 Fast Ethernet Switch User's Guide

Link Aggregation

Link aggregation allows several ports to be grouped together
and to act as a single link. This gives a bandwidth that is a
multiple of a single link's bandwidth.
Link aggregation is most commonly used to link a bandwidth
intensive network device or devices – such as a server – to the
backbone of a network.
The switch allows the creation of up to 6 link aggregation
groups, each group consisting of up of up to 8 links (ports). The
aggregated links must be contiguous (they must have
sequential port numbers) except the two (optional) Gigabit
ports – which can only belong to a single link aggregation
group. A link aggregation group may not cross an 8-port
boundary, starting with port 1 (a group may not contain ports 8
and 9, for example) and all of the ports in the group must be
members of the same VLAN. Further, the aggregated links
must all be of the same speed and should be configured as full-
duplex.
The configuration of the lowest numbered port in the group
becomes the configuration for all of the ports in the aggregation
group. This port is called the Master Port of the group, and all
configuration options – including the VLAN configuration – that
can be applied to the Master Port are applied to the entire link
aggregation group.
Load balancing is automatically applied to the ports in the
aggregated group, and a link failure within the group causes
the network traffic to be directed to the remaining links in the
group.
The Spanning Tree Protocol will treat a link aggregation group
as a single link, on the switch level. On the port level, the STP
will use the port parameters of the Master Port in the
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