5.8TB RAID5 SATA Array Questions

Nick Evans nevans at talkpoint.com
Fri Apr 15 07:45:40 PDT 2005

On Thu, 14 Apr 2005 17:13:48 -0500
"Edgar Martinez" <emartinez at crockettint.com> wrote:

> Benson..GREAT RESPONSE!! I Don't think I could have done any better myself.
> Although I knew most of the information you provided, it was good to know
> that my knowledge was not very far off. It's also reassuring that I'm not
> the only nut job building ludicrous systems..
> Nick, I believe that we may have some minor misinformation on our hands..
> I refer you both to http://www.freebsd.org/projects/bigdisk/ which according
> to the page.
> When the UFS filesystem was introduced to BSD in 1982, its use of 32 bit
> offsets and counters to address the storage was considered to be ahead of
> its time. Since most fixed-disk storage devices use 512 byte sectors, 32
> bits allowed for 2 Terabytes of storage. That was an almost un-imaginable
> quantity for the time. But now that 250 and 400 Gigabyte disks are available
> at consumer prices, it's trivial to build a hardware or software based
> storage array that can exceed 2TB for a few thousand dollars.
> The UFS2 filesystem was introduced in 2003 as a replacement to the original
> UFS and provides 64 bit counters and offsets. This allows for files and
> filesystems to grow to 2^73 bytes (2^64 * 512) in size and hopefully be
> sufficient for quite a long time. UFS2 largely solved the storage size
> limits imposed by the filesystem. Unfortunately, many tools and storage
> mechanisms still use or assume 32 bit values, often keeping FreeBSD limited
> to 2TB.
> So theoretically it should go over 1000TB.I've conducted several bastardized
> installations due to sysinstall not being able to do anything over the 2TB
> limit by creating the partition ahead of time.I am going to be attacking
> this tonight and my efforts will be primarily focused on creating one large
> 5.8TB slice..wish me luck!! 
> PS: Muhaa haa haa!

You'll need to use GPT to make this work for anything over 2TB. Man gpt


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