max. partition size on 5.x

Rainer Duffner rainer at
Mon Sep 13 15:09:39 PDT 2004

Brooks Davis wrote:

>On Mon, Sep 13, 2004 at 11:02:13PM +0200, Claus Guttesen wrote:
>> Hi.
>> Not shure whether this is the right place to ask, but
>> I haven't found other sources of information.
>> I deployed a beta3-nfs-server which works fine. Two
>> IDE-to-SCSI-cabinets are connected to the server using
>> an aic7899-controller. The first cabinet has approx. 2
>> TB (12 disks at 200 GB, as expected). When I connected
>> the second cabinet using 250 GB disks, I exptected
>> approx. 2.5 TB, but only saw 764 GB.
>> Is there any limit that is imposed by 5.x in terms of
>> max. partition size? This is running on a Compaq DL
>> 380 dual PIII (G2) with 3 GB RAM, microstorage
>> cabinet.
>> The raid-system became visible by the usual
>> 'camcontrol rescan all' and I used 'fdisk -I /dev/da2'
>> and 'disklabel -w /dev/da2s1'.
>The limit on the size of a disk is unreachable, but we have a lack of
>good partitioning tools at the moment. bsdlabel (the program formerly
>known as disklabel) is limited to 2TB.  Sunlabel appears to be limited
>to 16TB in 2TB partitions and fdisk is limited to 2TB due to bugs in
>the program and 4TB due to the actual format.  If you don't need to
>boot off the slice, you may wish to try gpt(8) which should support
>any disk money can buy, but which we can't currently boot off of GPT
>partitions.  I'm in the process of getting some documentation on this in
>to the handbook.

That would be a good idea.
The data in the handbook is seriously outdated (when was 3.0 "current"?).
(I wanted to file a PR, I swear, but that day the FreeBSD-website was 
down and later I forgot...<g>)

The question has come-up in various lists and newsgroup the last couple 
of weeks.
As IDE2SCSI RAIDs are getting increasingly cheap and big, this problem 
will show-up more often than not in the future.

A howto  for gpt would also be good.
Not that I need one now, but now that 1GB mail-storage has come en vogue....


~     Rainer Duffner - rainer at     ~
~           Freising - Munich - Germany           ~
~    Unix - Linux - BSD - OpenSource - Security   ~
~  ~

More information about the freebsd-current mailing list