I have a 3.0 production machine  with a large, (2.0TB) raidframe on it
which works fine.  This was the largest I could get to work because you
can't have more than 2^32 sectors represented on a disklabel.  I'm told
that larger raidframes would work, but that I would have to use the raw
partition and manually specify parameters to newfs to get the large
filesystem.  I decided that what I could do was setup multiple raidframes,
each using a portion of the large disks, which would fall in the 2.0TB
limit, and avoid any bugs which might fall out of not using valid disk
labels.
Here's what my uname, uptime  and df -k say.

%uptime
12:49PM  up 291 days, 23:20, 1 user, load averages: 0.15, 0.10, 0.09
%uname -a
NetBSD fs1.via.net 3.0_STABLE NetBSD 3.0_STABLE (FS1) #0: Wed May 17 14:21:28 PDT 2006  buhrow@lothlorien.nfbcal.org:/usr/src/sys/arch/i386/compile/FS1 i386
%df -k
Filesystem  1K-blocks      Used     Avail Capacity  Mounted on
/dev/wd0a    57223275    390715  53971397     0%    /
/dev/raid0a 2114337548 941320052 1067300620    46%    /home/backup
/dev/raid1a 758946265 196014385 524984567    27%    /home/backup/mail
On Mar 5,  2:31pm, der Mouse wrote:
} Subject: Big RAIDframe
} Is RAIDframe terabyte-clean?  In particular, if I RAIDframe together
} partitions so as to produce a RAID volume larger than 2TB, will the
} resulting volume work?  (Okay, let's say not, does it work, but raer,
} should it work.  Unless someone has experience saying it does, which
} would be very welcome.)
} 
} This is under 3.0.  If it doesn't work on 3.0 but does on something
} later, that information too would be welcome.  It's a live production
} machine with important data on it, so I can't casually try things that
} might roach the data.
} 
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