HP A3550A User Manual - A3661-90001 - Page 109

Table 2-4 High Availability, Distance, and Capacity Topology Error Recovery Failing Continue component after failure? What happens and how to recover Disk module Yes Applications continue to run on all supported RAID levels (RAID-1, 1/0, 3, and 5). The system administrator or service provider hotreplaces the failed disk module. SP Fan pack No on path to failed SP; Yes on alternate path through second SP Ownership of the failed SP's LUNs can transfer automatically to the remaining operational SP if primary and alternate paths have been configured in LVM. If so, LVM switches automatically and transparently to the alternate path. The system administrator or service provider hotreplaces the failed SP. Yes Applications continue to run. The system administrator or service provider hot-replaces the fan pack. Power supply unit HP FC-AL Hub Yes if three power supply units (required for high availability); No if two power supply units (no high availability) If all three power supply units required for high availability are present, applications continue to run when one power supply unit fails. The system administrator or service provider hot-replaces the failed power supply unit. If two power supply units are present the disk array fails. The system administrator or service provider replaces the failed power supply unit and the system administrator restarts the operating system and applications. No on path to failed hub; Yes on alternate path to other pair of hubs I/O operations fail along the path to the failed HP FC-AL Hub. I/O operations can transfer automatically to the other pair of cascaded HP FC-AL Hubs if primary and alternate paths have been configured in LVM. If so, LVM switches automatically and transparently to the alternate path. The authorized service provider hot-replaces the failed HP FC-AL Hub. FC I/O adapter No on path to failed adapter; Yes if array has dual SPs and alternate paths have been configured I/O operations fail along the path through the failed adapter. If the host has two FC adapters connected to a dual-SP disk array, the array can be accessed through the path to the operational adapter and SP if primary and alternate paths have been configured in LVM. If so, LVM switches automatically and transparently to the alternate path. The authorized service provider replaces the failed adapter and the system administrator restarts the operating system and applications. FC cable No on path to failed cable; Yes if array has dual SPs and alternate paths have been configured I/O operations fail along the path through the failed cable. If the host has two FC adapters connected to a dual-SP disk array, the array can be accessed through the operational path if primary and alternate paths have been configured in LVM. If so, LVM switches automatically and transparently to the alternate path. The authorized service provider hotreplaces the failed cable. Hardware Topologies High Availability, Distance, and Capacity Topology 2-17