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CrossLink Connections
Two or more
A CrossLink is a collection of identical parallel links between two switches or between a switch and an end node, aggregated to appear as one single link of the aggregate capacity. The traffic distribution mechanism attempts to balance the load on the individual links. If one of the links in a CrossLink fails, the traffic is automatically moved from this link and distributed among the other links, thus providing active resilience.
The CrossLink ports on a
The CrossLinks provide load distribution as well as resilience. In normal operation, the traffic is distributed on the physical ports of the CrossLink according to the frame MAC addresses. This ensures the sequence of a flow. Should a link fail or otherwise become inoperative, the switch dynamically redistributes the traffic to the remaining links. The CrossLink remains in operation as long as there is at least one link in operation. If a failed link is restored, traffic is once more redistributed to make use of the restored link.
A CrossLink is in many ways operating as one single link. For example, the spanning tree protocol will only have one port entity covering all ports in the CrossLink. The ports will all have the same operating state. As for VLAN and CRF configuration, the CrossLink is also seen as one link. Configuration changes apply to all links in the CrossLink.
On the
The CrossLink concept is designed to be compatible with the coming Link Aggregation standard, IEEE 802.3ad.
On SmartStack
The
Switch Overview | SmartStack |