HP Compaq Integrated Smart Array Controller - Manual (Page 18)

1-4 Compaq Integrated Smart Array Controller User Guide
Compaq Confidential – Need to Know Required
Writer: CDresden Project: Compaq Integrated Smart Array Controller User Guide Comments:
Part Number: 153236-001 File Name: b-ch1 Controller Features.doc Last Saved On: 8/26/99 8:09 PM
Fault Tolerance
Fault tolerance relies on various methods for protecting data from loss in the
event of a hardware failure somewhere in the storage system. Each method has
its advantages, so choosing one requires careful planning for your particular
requirements.
Fault-tolerance methods supported by the Integrated Smart Array Controller
and the Compaq Array Configuration Utility include:
■ Distributed data guarding (RAID 5)
■ Drive mirroring (RAID 1)
■ Drive striping and mirroring (RAID 0+1)
■ No-fault tolerance (RAID 0)
■ Further data protection achieved by assigning an online spare to any
RAID 0+1, RAID 1, or RAID 5 configuration
See Appendix B for more information on fault-tolerance methods supported by
the Integrated Smart Array Controller. Chapter 6, “Compaq Array
Configuration Utility,” contains information on configuring your system for
each of the fault-tolerance methods.
Drive Movement
An array of drives can be moved from one system to another as long as the
relative order of the drives is maintained. However, when the relative order of
the drives is changed, or if a new array controller is installed or reconfigured,
all data stored on the drives are affected. For more information, refer to
Chapter 6 in this guide.
Read-Cache Memory
The Integrated Smart Array Controller has 16 MB of total memory, with 8 MB
dedicated for read-ahead cache.