Compaq ProLiant 6500 Compaq Parallel Database Cluster Model PDC/O2000 for Orac - Page 126

4-18 Compaq Parallel Database Cluster Model PDC/O2000 for Oracle8i and Windows 2000 Administrator Guide The following general guidelines apply to RAID selection for a cluster with RA4000/RA4100 Arrays using Oracle8i Parallel Server: I Oracle recommends that some form of disk fault tolerance be implemented in the cluster. I In order to ease the difficulty of managing dynamic space allocation in an Oracle Parallel Server raw volume environment, Oracle recommends the creation of "spare" raw volumes that can be used to dynamically extend tablespaces when the existing datafiles approach capacity. The number of these spare raw volumes should represent from 10 to 30 percent of the total database size. To allow for effective load balancing, the spares should be spread across a number of disks and controllers. The database administrator should decide, on a case by case basis, which spare volume to use based on which volume would have the least impact on scalability (for both speedup and scaleup). Planning the Grouping of Physical Disk Storage Space Figure 4-5 shows how the physical storage space in one RA4000/RA4100 Array that contains eight physical disk drives might be grouped for an Oracle8i Parallel Server database. RA4000/4100 Array Disk Disk Disk Disk Disk Disk Disk Disk Drive Drive Drive Drive Drive Drive Drive Drive Create logical drive arrays with Compaq Array Configuration Utility RAID 5 Disk Array RAID 1 Disk Array RAID 1 Disk Array Create extended partitions with Disk Management Create logical partitions with Disk Management Extended Partition / D / E / F / G /H / I / J / Extended Partition Extended Partition / K / L / / M / N / Figure 4-5. RA4000/RA4100 Array disk grouping for a PDC/O2000 cluster