2TB size limit on PERC4/ei?

[Matt Domsch]

On Tue, Aug 22, 2006 at 10:09:57AM -0500, Patrick_Boyd at dell.com wrote:
> SCSI is a 32bit protocol. This yeilds a limit of 2TB for addressable
> space using the SCSI protocol.

There are various sized block address widths in the SCSI protocol.  6,
10, and now 16-byte CDBs, with 16-byte necessary to handle >2TB block
addressing.  Alas few controllers yet actually support such large
devices.

You can use LVM to build a large block device based on smaller
physical (or hardware RAID logical) drives.  To be careful, I wouldn't
make one drive exactly 2TB and the other 400GB; instead make each
1.6GB and then use LVM on top of them.

Thanks,
Matt

-- 
Matt Domsch
Software Architect
Dell Linux Solutions linux.dell.com & www.dell.com/linux
Linux on Dell mailing lists @ http://lists.us.dell.com