HP A3550A User Manual - A3661-90001 - Page 99

Table 2-1 Basic 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 in single- No SP array (no high availability) SP in dual-SP disk array No on path to failed SP; Yes on alternate path through second SP The disk array fails. The system administrator or service provider replaces the SP and the system administrator restarts the operating system and applications. 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 SP. Fan pack Power supply unit FC I/O adapter FC cable Yes Applications continue to run. The system administrator or service provider hot-replaces the fan pack. Yes if three power supply units; No if two power supply units (no high availability) If three power supply units 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 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. 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 Basic Topology 2-7