Smart Array 5i Plus Controller and Battery Backed Write Cache Enabler User Guide

Compaq Smart Array 5i Plus Controller and Battery Backed Write Cache User Guide D-1
COMPAQ CONFIDENTIAL
Writer: Amy L. Laffitte File Name: m-appd Hard Drive Installation and Replacement
Codename: Executor Part Number: 266328-001 Last Saved On: 4/18/02 2:51 PM
D
Hard Drive Installation and Replacement
Each SCSI channel on a Smart Array controller supports up to 14 drives. Drives can
be of the Wide Ultra3 SCSI or Wide Ultra2 SCSI type.
Each drive on a SCSI bus must have a unique ID value in the range 0 to 15 (except
ID 7, which is reserved for controller use). This value is set automatically on hot-
pluggable drives in Compaq ProLiant
TM
servers and storage systems, but values for
other drives must be set manually.
• Do not terminate the drives. Compaq servers and internal cabling provide the
required termination of the SCSI bus.
• Do not use drives of different capacity in the same array. The excess capacity of
larger drives cannot be used by the array and is wasted.
• Do not combine hot-pluggable drives with non-hot-pluggable drives on the same
SCSI bus.
Hard drives that are currently supported by the Smart Array Controller are listed at
www.compaq.com/products/storageworks/.
General Information About Hard Drive Failure
When a hard drive fails, all logical drives that are in the same array will be affected.
Each logical drive in an array may be using a different fault-tolerance method, so
each logical drive can be affected differently.
• RAID 0 configurations cannot tolerate drive failure. If any physical drive in the
array fails, all non-fault-tolerant (RAID 0) logical drives in the same array will
also fail.