On Fri, Dec 23, 2011 at 01:21:20PM +0000, keith wrote:
> On 22/12/2011 21:36, Keith wrote:
> >I am having some trouble getting 4 x 2TB sata disks into one big
> >single softraid (raid 5) disk. I can create the softraid0 disk and
> >it's 5.5TB want would like to get a single 5.5TB partition but can
> >only make one single 1.5TB partition! Can someone tell me where
> >I'm going wrong.
> >
> >Thanks
> >Keith
> >
> >===================
> >
> >Start from fresh and delete softraid0 disk...
> >#bioctl -d sd0
> >
> >## Wipe the first part of the disks.
> >#dd if=/dev/zero of=/dev/rwd0c bs=10m count=1
> >#dd if=/dev/zero of=/dev/rwd1c bs=10m count=1
> >#dd if=/dev/zero of=/dev/rwd2c bs=10m count=1
> >#dd if=/dev/zero of=/dev/rwd3c bs=10m count=1
> >
> >#fdisk -iy wd0
> >#fdisk -iy wd1
> >#fdisk -iy wd2
> >#fdisk -iy wd3
> >
> >## Make a partition of type RAID
> >#printf "a\n\n\n\nRAID\nw\nq\n\n" | disklabel -E wd0
> >#printf "a\n\n\n\nRAID\nw\nq\n\n" | disklabel -E wd1
> >#printf "a\n\n\n\nRAID\nw\nq\n\n" | disklabel -E wd2
> >#printf "a\n\n\n\nRAID\nw\nq\n\n" | disklabel -E wd3
> >
> >#bioctl -c 5 -l /dev/wd0a,/dev/wd1a,/dev/wd2a,/dev/wd3a softraid0
> >
> >sd1 at scsibus3 targ 1 lun 0: <OPENBSD, SR RAID 5, 004> SCSI2
> >0/direct fixed
> >sd1: 5723178MB, 512 bytes/sector, 11721070080 sectors
> >
> >#dd if=/dev/zero of=/dev/rsd1c bs=1m count=1
> >
> >#fdisk -iy sd1
> >
> >This give me....
> >
> ># fdisk -e sd1
> >Enter 'help' for information
> >fdisk: 1> p
> >Disk: sd1 geometry: 729602/255/63 [3131135488 Sectors]
> >Offset: 0 Signature: 0xAA55
> > Starting Ending LBA Info:
> > #: id C H S - C H S [ start: size ]
> >-------------------------------------------------------------------------------
> >
> > 0: 00 0 0 0 - 0 0 0 [ 0: 0
> >] unused
> > 1: 00 0 0 0 - 0 0 0 [ 0: 0
> >] unused
> > 2: 00 0 0 0 - 0 0 0 [ 0: 0
> >] unused
> >*3: A6 0 1 2 - 194903 76 55 [ 64: 3131121474
> >] OpenBSD
> >
> >Then I try and partition the disk.....
> >
> ># disklabel -E sd1
> >Label editor (enter '?' for help at any prompt)
> >> a a
> >offset: [64]
> >size: [3131121474]
> >FS type: [4.2BSD]
> >> p T
> >OpenBSD area: 64-3131121538; size: 1.5T; free: 0.0T
> ># size offset fstype [fsize bsize cpg]
> > a: 1.5T 64 4.2BSD 8192 65536 1
> > c: 5.5T 0 unused
> >>
> >
> >
>
> It seems like an fdisk issue to me. If I just use one 2TB sata disk
> and create the biggest partition I can using fdisk then I get a
> 1.8TB partition. If I do the same on a softraid (raid 5) partition
> using 4 of the 2TB disks the biggest partition I can make is just
> 1.5TB but the actual softraid disk is apparently 5723178MB (5.4TB)
>
> I was trying to get some details from fdisk to put here but i've
> just run "fdisk -i sd0" on the wrong disk and trashed the boot
> disk!!!! I can't run the reboot command either as it just gives
> "Segmentation fault".
>
> Keith
As Christian Weisgerber (aka naddy) already told you, the original
problem can be fixed using the 'b' command within disklabel.
But now I'm afraid you trashed some vital info. Booting form another
cd or hard disk can help you solve the probem of repairing the mbr
partition map and boot info. man installboot contains some help.
-Ott
