D-Link TM DES-6500, Manual

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DES-6500 Chassis-based Layer 3 Ethernet Switch Manual
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Link Aggregation
Understanding Port Trunk Groups
Port trunk groups are used to combine a number of ports together to make a single high-bandwidth data pipeline.
The DES-6500 switch supports up to 32 port trunk groups with 2 to 8 ports in each group. A potential bit rate of 8000
Mbps can be achieved.
Figure 6- 6. Example of Port Trunk Group
The Switch treats all ports in a trunk group as a single port. Data transmitted to a specific host (destination address) will
always be transmitted over the same port in a trunk group. This allows packets in a data stream to arrive in the same order
they were sent.
NOTE: If any ports within the trunk group become disconnected, packets
intended for the disconnected port will be load shared among the other
uplinked ports of the link aggregation group.
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 32 link aggregation groups, each group consisting of 2 to 8 links (ports). All of the
ports in the group must be members of the same VLAN, and their STP status, static multicast, traffic control, traffic
segmentation and 802.1p default priority configurations must be identical. Port locking, port mirroring and 802.1X must
not be enabled on the trunk group. Further, the aggregated links must all be of the same speed and should be configured as
full-duplex.
The Master Port of the group is to be configured by the user, 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.