On Mon, 24 Oct 2005, Nick Nauwelaerts wrote:
> On Mon, 24 Oct 2005 11:42:45 +0200 (CEST)
> Beck Zoltan Gyula <[EMAIL PROTECTED]> wrote:
>
> > I would like to ask if it is possible to use a large, more than 2T
> > diskarray or CCD?
> > In FAQ: "14.7 - What are the issues regarding large
> > drives with OpenBSD?
> >
> > OpenBSD supports an individual file system of up to 231-1, or
> > 2,147,483,647 sectors, and as each sector is 512 bytes, that's a tiny
> > amount less than 1T."
>
> I might be wrong, it's been a while. But if I'm not mistaken I did
> successfully mount a 5TB partition over nfs from a netapp unit. If
> that's the storage you require, you might be more interested in those
> units (with an added bonus that they come up in less than a minute after
> an unclean shutdown).
>
> And if you really want the maximum size for partitions on OpenBSD (just
> under 1TB), then don't forget to read up on fsck memory usage.
And don't forget another thing.
There's also the issue of disk size. You might have a disk that is
larger than 1TB, and try to create partitions smaller than 1TB.
In theory that should not work, since a partition that crosses the 1TB
boundary or is completely beyond 1TB causes sign wraps in block
numbers.
But in practise it may work. Due to some luck, the SCSI code converts
the block numbers in such a way that the sign wrap does not occur, or
at least its effects are reversed. I managed to create 900GB and a
300GB partition on a 1.2TB RAID0, that worked fine.
THAT IS NOT A GUARANTEE.
The very hard limit to disk and partition size is 2TB. To be safe,
Both should be smaller than 1TB.
-Otto
