James,
There are currently 128 possible SCSI disk device allocated in the
device map--see linux/Documentation/devices.txt . Now, each of these
supports partitions 1..15 (lower 4 bits) with 0 being the raw device,
and the other bits for the base device are mapped into various places.
There is a slight chance of modifying things so that you have less
partition bits and give those unused bits to the base scsi devices. I
don't know how well disciplined the scsi code is in using the conversion
macros from device and partition to device number.
You have another problem with the md driver (raid). It's superblock is
coded to allow raid sets of up to 11 devices (12 if you count the
spare.) This is a #define set to 12. You should be able increase this
value to 16 and recompile the kernel and tools.
I have heard of a large file patch for ext2 filesystem that you may be
able to use. FYI: the ext2 filesystem is limited to 1-Terabyte maximum
per volume.
<>< Lance.
[EMAIL PROTECTED] wrote:
>
> > The Software RAID solution will give you all the flexibility you need.
> > If you have already considered it, and discarded it as an option for
> > some reason, I'd be grateful to know about that reason.
>
> The 16-scsi-drive limitation that existed (at least at one time).
> While the limit may be higher now, being over 240 (ideally 256 minimum
> seems unlikely (would require 16 device major's afaict, at least with
> the current partition/minor config). If this limitation is gone, I
> would *love* to do pure s/w raid, that's for sure...
>
> James
> --
> Miscellaneous Engineer --- IBM Netfinity Performance Development
