HP StorageWorks 8/80 HP StorageWorks Fabric OS 6.1.x administrator guide (5697 - Page 382

Table 88 Using FCIP fastwrite and tape pipelining (continued) FCIP fastwrite Tape pipelining Class 3 traffic is accelerated with fastwrite. Class 3 traffic is accelerated between host and sequential device. With sequential devices (tape drives), there are 1024 initiator-tape (IT) pairs per GbE port, but 2048 initiator-tape-LUN (ITL) pairs per GbE port. The ITL pairs are shared among the IT pairs. For example: Two ITL pairs for each IT pair as long as the target has two LUNs. If a target has 32 LUNs, 32 ITL pairs for IT pairs. In this case, only 64 IT pairs are associated with ITL pairs. The rest of the IT pairs are not associated to any ITL pairs, so no tape pipelining is performed for those pairs. By default, only fastwrite-based acceleration is performed on the unassociated pairs. Does not support multiple non-equal-cost path between host and sequential device FCIP fastwrite/tape pipelining configurations To help understand the supported configurations, consider the configurations shown in the two figures below. In both cases, there are no multiple equal-cost paths. In the first figure, there is a single tunnel with fastwrite and tape pipelining enabled. In the second figure, there are multiple tunnels, but none of them create a multiple equal-cost path. Connection can be VE-VE or VEX-VE Figure 44 Single tunnel, fastwrite and tape pipelining enabled 382 Configuring and monitoring FCIP extension services