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The preferred practice for the 2145-SV1 is similar. The significant change is on the slot placement, and that there is no dual port HBA configuration option, as shown in Figure 1-13. 

<img src='content_image/969901.jpg'>

Due to the new port availability on the 2145-DH8 and 2145-SV1, and the increased bandwidth with the 16 Gb ports, it is possible to segregate the port assignment between hosts and storage, thus isolating their traffic. 

Host and storage ports have different traffic behavior, so keeping host and storage ports together produces maximum port performance and utilization by benefiting from its full duplex bandwidth. For this reason, sharing host and storage traffic in the same ports is generally the preferred practice. However, traffic segregation can also provide some benefits in terms of troubleshooting and host zoning management. Consider, for instance, SAN congestion conditions due to a slow draining device. 

In this case, segregating the ports simplifies the identification of the device causing the problem. At the same time, it limits the effects of the congestion to the hosts or backend ports only. Furthermore, dedicating ports for host traffic reduces the possible combinations of host zoning and simplifies SAN management. It is advised to implement the port traffic segregation with configurations with a suitable number of ports (that is, 12 ports or more) only. 

Important:  Use port masking to assign specific uses to the SAN Volume Controller ports. For more information, see Chapter 6, “Hosts” on page 279. 

