Determining Disk Offset When Configuring a RAID 5 Volume under Windows 2003 Server

[Tony Leete]

I am trying to determine the required offset for a RAID 5 Volume 5x146G SAS 2.5" drives attached to a Smart Array P800 Controller. Volume is presetned to windows as follows:

---- Drive 0 Geometry Infomation ----
Cylinders = 140531
TracksPerCylinder = 255
SectorsPerTrack = 32
BytesPerSector = 512
DiskSize = 587127275520 (Bytes) = 559928 (MB)

---- Drive Partition 0 Infomation ----
StatringOffset = 16384
PartitionLength = 587127062528
HiddenSectors = 32
PartitionNumber = 1
PartitionType = 7

End of partition information. Total existing partitions: 1

This drive is dedicated to SQL 2005 Data with default allocation unit set to 64k. I have tried various combinations of offsets, yet Sql 2005 BPA has problems with the offsets.

Anyone run into this? or can lead in the right direction?

[Andrew Barcus]

Use Diskpart to create the proper offset instead of partitioning with Windows tools:

Diskpart commands
Select Disk X
Create Partition Primary align=64

Afterward format disks which will store SQL data using (disk management rather than right click/format) with 64KB block size.