HP Surestore Disk Array FC60 HP SureStore E Disk Array FC60 Service Manual (A5 - Page 104

High Availability Topologies Figure 39 through Figure 42 illustrate high availability topologies. These topologies achieve the highest level of availability because they have fully redundant hardware data paths to each disk array. There are no single points of failure in these topologies. These topologies are more complex and expensive to implement than non-high availability topologies. Characteristics • The direct connect topology (Figure 39) achieves high availability by providing redundant data paths between the host and the disk array, but this configuration also provides limited distance and connectivity. • The use of multiple hubs creates redundant data paths between all hosts and all disk arrays. Multiple hubs also provides greater connectivity, increasing the number of disk arrays and host that can be interconnected. • The use of hubs and switches increases the distance that can be achieved between the host and the Disk Array FC60. The host and hub can be up to 500 meters apart, and the distance from the hub to the disk arrays can be an additional 500 meters. 104 Topologies for Windows NT and Windows 2000