DELL N3000 User Manual

Configuring Data Center Bridging Features

To consolidate different traffic classes within different traffic types in a 

typical DCB environment, ETS provides an operational model for 

prioritization and bandwidth allocation for traffic. Figure 29-3 illustrates a 

typical example that consolidates three traffic types on a single 10GE link. For 

consolidation to be effective all traffic types must be serviced according to 

their requirements. For instance, SAN traffic must be guaranteed to be 

lossless, and the server cluster traffic (IPC) should be guaranteed a 

sufficiently high priority to meet the requirement of low latency.

In this example, to ensure that the server cluster traffic has low latency, it may 

be assigned to a TCG—say, TCG0—and a strict mode of scheduling is 

enabled on this group (weight set to 0%). SAN traffic can be assigned to 

TCG1 and LAN to TCG2. The TCG1 and TCG2 can be set to a weight of 

50% each. With these configurations, Figure 29-3 illustrates how the load is 

managed at different times.
When the offered load is 3 Gbps for each traffic type at time t1, the allocated 

bandwidth for TCG1 and TCG2 is 3.5 Gbps each. All traffic types, including 

IPC, SAN, and LAN, are allowed to be transmitted, since the offered load is 

under the allocated bandwidth.