Link Aggregation - D-Link xStack DES-3800 Series User Manual

xStack DES-3800 Series Layer 3 Stackable Fast Ethernet Managed Switch
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). The aggregated
links must be contiguous (they must have sequential port numbers) except the four (optional) Gigabit ports, which can only belong
to a single link aggregation group. 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.
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 calculation of port cost and in determining the state of the link aggregation group.
If two redundant link aggregation groups are configured on the Switch, STP will block one entire group; in the same way STP will
block a single port that has a redundant link.

Link Aggregation

To configure port trunking, click L2 Features > Trunking > Link Aggregation to display the following window:
Figure 7- 15. Port Link Aggregation Group window
To configure port trunk groups, click the Add button to add a new trunk group and use the Link Aggregation Group
Configuration window (see example below) to set up trunk groups. To modify a port trunk group, click the Hyperlinked Group
ID. To delete a port trunk group, click the corresponding under the Delete heading in the Link Aggregation Group Entries
table.
Figure 7- 16. Link Aggregation Group Configuration – Add
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