I work for a company with a 15 TB SAN.  All opinions about the
disadvantages of creating really large filesystems aside, I'm trying to
find out what is the maximum filesystem size we can allocate on our SAN
that a linux box (x86) can really use.

I seem to be finding (from various posts on newsgroups and the kernel
source itself) that block devices with 2.4 kernels cannot exceed 2 TB,
so no matter what the filesystem can theoretically handle, 2 TB is the
practical limit.

I've read that XFS filesystems can theoretically be created up to 18
million TB in size.

What I can't seem to find anywhere is whether the 2 TB block device
limit has improved/grown with 2.6 kernels (on x86 hardware).  Perhaps
I've looked in the wrong places, but I haven't found anything.

If you have any helpful information, or can point me towards a better
place to look I would be very appreciative.

I am not joined to this list, so if you can CC: me in the reply I would
also be grateful.

Aaron