HP StorageWorks 2/24 FW 07.00.00/HAFM SW 08.06.00 McDATA Products in a SAN Env - Page 108

Planning Considerations for Fibre Channel Topologies 3 • Bandwidth - ISL connections can be used to increase the total bandwidth available for data transfer between two directors or switches in a fabric. Increasing the number of ISLs between elements increases the corresponding total ISL bandwidth but decreases the number of port connections available to devices. Table 3-1 illustrates ISL transfer rate versus port availability for a fabric consisting of two Intrepid 6064 Directors. Table 3-1 ISL Transfer Rate Versus Fabric Port Availability (Two-Director Fabric) Number of ISL Data Transfer Rate ISLs (at 1.0626 Gbps) 1 1.0625 Gbps 2 2.1250 Gbps 3 3.1875 Gbps 4 4.2500 Gbps 5 5.3125 Gbps 6 6.3750 Gbps 7 7.4375 Gbps 8 8.5000 Gbps ISL Data Transfer Rate (at 2.1250 Gbps) 2.1250 Gbps 4.2500 Gbps 6.3750 Gbps 8.5000 Gbps 10.6250 Gbps 12.7500 Gbps 14.8750 Gbps 17.0000 Gbps Available Fabric Ports 126 124 122 120 118 116 114 112 • Load balancing - Planning consideration must be given to the amount of data traffic expected through the fabric or through a fabric element. Because the fabric automatically determines and uses the least cost (shortest) data transfer path between source and destination ports, some ISL connections may provide insufficient bandwidth while the bandwidth of other connections is unused. To optimize bandwidth use and automatically provide dynamic load balancing across multiple ISLs, consider purchasing and enabling the OpenTrunking feature key. For information about the feature and managing multiple ISLs, refer to OpenTrunking and General Fabric Design Considerations. 3-22 McDATA Products in a SAN Environment - Planning Manual