HP P6300 HP P6300/P6500 EVA Installation Guide (5697-2485, September 2013) - Page 7

• Implement switches with full-duplex non-blocking mesh backplanes with sufficient port buffer cache (at least 512 KB per port). • Implement flow control on the storage network switch infrastructure. Flow control can dramatically impact performance in a 10 GbE environment. This is especially true in mixed 1 GbE and 10 GbE environments. When a network port becomes saturated, excess frames may be dropped because the port cannot physically handle the amount of traffic received. This causes the packets to be resent, and the overhead of resending the packets can decrease performance. For example, if a 10 GbE link sends data at 10 Gb/s to a single 1 GbE link, flow control eliminates any problems by controlling the speed at which data is sent to the port. Best practices dictate that flow control always be enabled and it must be enabled on both the switches and the NICs/iSCSI initiators to function properly. If it is not enabled everywhere, the network defaults to the lowest common denominator, which is flow control disabled. • (Optional) Implement jumbo frames support on the switch, the 1 GbE iSCSI modules, and the 10 GbE iSCSI/FCoE modules when iSCSI is configured, and all servers connected to the IP-SAN. Consider using 4K jumbo frames instead of 9K jumbo frames for better streaming performance. Jumbo frames cannot be configured and are not supported by the iSCSI and iSCSI/FCoE module's Ethernet management port, a normal 1500 byte MTU is the default setting. NOTE: FCoE requires jumbo frames and is the default configuration of a converged network adapter, converged network switch, and the 10 GbE iSCSI/FCoE modules when FCoE is configured. Recommended switch infrastructure for an IP-SAN HP does not recommend a particular IP switch. However, there are minimum switch capabilities that make building a high-performance, fault-tolerant storage network a relatively easy and cost effective task. As a general rule, any enterprise-class managed switch typically has the capabilities most IP-SAN customers require. Table 1 (page 7) summarizes the minimum recommended switch capabilities for a P6000-based IP-SAN. For FCoE, HP recommends converged network switches. For more information about these switches, go to: http://h18006.www1.hp.com/storage/networking/index.html These switches are also referenced in the HP SAN Design Reference Guide, which is also available through this website. Table 1 Minimum recommended switch capabilities for a P63x0/P65x0 EVA-based IP-SAN Switch capability 1 and 10 gigabit Ethernet support Fully subscribed non-blocking backplanes Adequate per port buffer cache Description The iSCSI module option of the P6000 comes equipped with eight copper gigabit Ethernet ports (802.3ab). To take advantage of full duplex gigabit capabilities, the cabling infrastructure must be Cat5e or Cat6 cabling. The iSCSI/FCoE module option of the P6000 comes equipped with four SFP+ 10 gigabit ports, and you configure either SFP+ optical or SFP+ copper connectivity. Server connections and switch interconnects can be done with SFP+ fiber and SFP+ copper cabling, in addition to Cat5e or Cat6 cabling, depending on IP switch capabilities. In order to achieve maximum performance on the IP-SAN it is important to select a switch that has a fully subscribed backplane. This means that the backplane is capable of supporting all ports at full-duplex mode. For instance, if the switch has 24 gigabit ports, it will have to have a 48 gigabit backplane to support full duplex gigabit communications. For optimal switch performance, HP recommends that the switch have at least 512 KB of buffer cache per port. Consult your switch manufacturer specifications for the total buffer cache. For example, if the switch has 48 gigabit ports, this recommendation is to have at least 24 MB of buffer cache dedicated to those ports. If the switch aggregates Plan your storage configuration 7