HP High Availability Disk Array 10/20 User Guide - Page 127

Two-adapter/Two SP One host Two SCSI-2 adapters Two SCSI-2 buses Two SPs Multi-bus Two hosts Two SCSI-2 adapters (one per host) Two SCSI-2 buses (one per host) Two SPs Provides highest availability and best array performance for singlehost configurations. With RAID of any supported level, applications can continue to run after failure of a disk module. If one SP fails, the System Administrator must reassign ownership of the failed SP's LUNs to the operational SP by using Grid Manager. Also, the path to the operational SP must be used and can be changed with SYSGEN or ioconfig. Once these changes have been made, access to all LUNs on the array within the SCSI LUN limits is possible. If the SCSI-2 adapter fails, the System Administrator can access the array through the operational SCSI-2 adapter's path. LUN ownership and path changes must be reassigned by using Grid Manager and SYSGEN/ioconfig. Resembles two basic configurations side-by-side and provides modest high availability with the SCSI-2 buses not shared between two hosts. With MPE/iX supported RAID levels, applications can continue to run if a disk module fails. If one SP fails, the System Administrator can access the LUNs owned by the failed SP by accessing the remaining operational SP with the other host. If a host adapter fails, the System Administrator can access the LUNs in the array with the other host adapter. The System Administrator must change the path and the SP ownership of the LUNs for the failed SP or failed host adapter by using SYSGEN/ioconfig and Grid Manager, respectively. 5-4