Ultan Kinahan

An important piece of info for anyone looking to attach storage to a server in excess of 2TB;

With Windows Server 2003 Service Pack 1 (SP1) and Windows XP 64-bit Edition (x64), these limits have changed.

Microsoft added support for 64-bit block numbers in the disk/class layer, using the new SCSI Commands included in the SCSI-3 Block Commands-2 command set. Microsoft also enabled GPT support for all Windows Server 2003 SP1 platforms. With this change, for example, a snapshot of a GPT partition on an Itanium-based machine can now be transported to a 32-bit machine for data mining or archiving purposes.

The new limits are as follows:

• Basic or dynamic volume size: 2⁶⁴ blocks = 2⁷³ bytes (too big to pronounce)
• Maximum NTFS file system size that can be realized on Windows: 256 TB

Note: Disk devices with more than 2 TB of disk space must be converted to GPT format for all of the disk space to be usable. If the device uses MBR format, the disk space beyond 2 TB will be unusable.

See more at: http://www.microsoft.com/whdc/device/storage/LUN_SP1.mspx#EFB