Create 5TB partition in Linux 2.6?

We are setting up a new backup server and it has 8 - 750GB SATA drives in a RAID 5 configuration.  We set aside 50GB for our various system partitions, leaving the remaining space for backup storage.  Of course, we've run into the 2TB limit for standard FDISK operations.

How can we format this nearly-5TB space into one partition on SUSE 10.2 64-bit?  I thought we might have an answer with "fdisk -b2048 /dev/sdb" (the 2kb block size is supposed to allow for 8TB filesystems), but it didn't work.

Is there something we need to set with CONFIG_LBD? or some other (sfdisk) command we need to use?

Any input is appreciated!
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e_sandrsAuthor Commented:
Hmmm, some materials from 3Ware discuss using parted to create the large partition.  I tried it, it worked, and then I could use mkfs with the -b switch to format the entire 5TB.  We need to test this and see if disc performance is as expected...

noci:  Why not one large partition?  The sole purpose of this space is storing backups - is there some advantage we'd get of having 3 partitions of 1.5TB?  It seems like it would just create a hassle in keeping the backup data spread across the available space, but I'm not used to working at these volume sizes - so we could be missing something obvious...
nociSoftware EngineerCommented:
The 2TB size comes from the basic 4G (=32bits unsigned MAXINT) number of blocks * 0.5K bytes per block.
Drive geometry is reported by the device itself ==> enlarging the sectorsize doesn't work.
Unless the disk supports it.

BTW, Why create one large partition....
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nociSoftware EngineerCommented:
LVM as dlangr proposed won't solve the problem of your existing volume, but is an approach to start again.
With raid5 on 4 disks you still have a slightly larger volume (750 *3 GB > 2TiB (it is sbout 2.05 TiB)
(2 such raidsets would cost you another 750GB. for the extra striping). It loses you about 100Gib this way.

(GB=1000*1000*1000 Bytes, Gib = 1024*1024*1024 Bytes)
nociSoftware EngineerCommented:
And I forgot to say use LVM to stich the two RAID sets together.
LVM gives you  a lot of flexibility, did you take it into consideration? See my first comment.

LVM is very usefull to devide raid devices into either 1 big or sevral smaller partitions.

I noticed my previous link (1st post) was broken, here is the right one:

Beside that the LVM can:

    * Resize volume groups online by absorbing new physical volumes (PV) or ejecting existing ones.
    * Resize logical volumes online by concatenating extents onto them or truncating extents from them.
    * Create read-only snapshots of logical volumes (LVM1).
    * Create read-write snapshots of logical volumes (LVM2).
    * Stripe whole or parts of logical volumes across multiple PVs, in a fashion similar to RAID0.
    * Mirror whole or parts of logical volumes, in a fashion similar to RAID1
    * Move online logical volumes between PVs.
    * Split or merge volume groups in situ (as long as no logical volumes span the split). This can be useful when migrating whole logical volumes to or from offline storage.
nociSoftware EngineerCommented:
No problem
Closed, 125 points refunded.
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