topic Re: Can I convert 520 bytes per sector disks to 512 bytes per sector disk? in Disk

Can I convert 520 bytes per sector disks to 512 bytes per sector disk?

Craig Stephens — Thu, 29 Mar 2007 10:07:54 GMT

I have a load of 73Gb and 36Gb disks from an old VA, which I am hoping to use in some DS2405s and use them as JBODs. Is this possible?

If I run a diskinfo on these disks they read as 520 bytes per sector rather than 512.

Is it possible to format them to 512 bytes per sector?

I've been looking around and was looking down the "JBODfmt" route but I'm not sure if this is the right way forward?

Re: Can I convert 520 bytes per sector disks to 512 bytes per sector disk?

Steven E. Protter — Thu, 29 Mar 2007 10:16:19 GMT

Shalom,

The right way to go is to be happy the disks are recognized in the jbod, see if they can be configured with pvcreate.

Any other course of action is very likely to leave you with a pile of bricks to get rid of.

SEP

Re: Can I convert 520 bytes per sector disks to 512 bytes per sector disk?

Patrick Wallek — Thu, 29 Mar 2007 10:24:16 GMT

Craig,

Yes you can use JBODfmt to change the sector size back to 512.

The following document talks very briefly about this:

Submitted Date: 6/11/03
Title: Pvcreate command hangs on JBOD 2405 disks
Document ID: KBRC00012640
Last Modified Date: 8/4/05
http://www2.itrc.hp.com/service/cki/docDisplay.do?docLocale=en_US&docId=200000079998787

Re: Can I convert 520 bytes per sector disks to 512 bytes per sector disk?

Craig Stephens — Thu, 29 Mar 2007 10:53:08 GMT

Some more info.....

512 bytes per sector disk
=========================

# mkdir /dev/vg01
# mknod /dev/vg01/group c 64 0x010000
# diskinfo /dev/rdsk/c7t11d0
SCSI describe of /dev/rdsk/c7t11d0:
vendor: HP 73.4G
product id: ST373405FC
type: direct access
size: 71687369 Kbytes
bytes per sector: 512
# pvcreate -f /dev/rdsk/c7t11d0
Physical volume "/dev/rdsk/c7t11d0" has been successfully created.
# vgcreate /dev/vg01 /dev/dsk/c7t11d0
Increased the number of physical extents per physical volume to 17501.
# pvdisplay /dev/dsk/c7t11d0
--- Physical volumes ---
PV Name /dev/dsk/c7t11d0
VG Name /dev/vg01
PV Status available
Allocatable yes
VGDA 2
Cur LV 0
PE Size (Mbytes) 4
Total PE 17499
Free PE 17499
Allocated PE 0
Stale PE 0
IO Timeout (Seconds) default
Autoswitch On

520 bytes per sector disk
=========================
# mkdir /dev/vg02
# mknod /dev/vg02/group c 64 0x020000
# diskinfo /dev/rdsk/c7t12d0
SCSI describe of /dev/rdsk/c7t12d0:
vendor: HP 36.4G
product id: ST336753FC
type: direct access
size: 70000000 Kbytes
bytes per sector: 520
# pvcreate -f /dev/rdsk/c7t12d0
Physical volume "/dev/rdsk/c7t12d0" has been successfully created.
# vgcreate /dev/vg02 /dev/dsk/c7t12d0
vgcreate: Physical Volume "/dev/dsk/c7t12d0" contains no LVM information

Re: Can I convert 520 bytes per sector disks to 512 bytes per sector disk?

Craig Stephens — Thu, 29 Mar 2007 11:20:06 GMT

HP StorageWorks Command View VA 1.09.02 is installed.

The ioscan output of the hardware path is as follows:
# ioscan -fnH1/4/0/0
Class I H/W Path Driver S/W State H/W Type Description
======================================================================
fc 0 1/4/0/0 td CLAIMED INTERFACE HP Tachyon XL2 Fibre Channel Mass Storage Adapter
/dev/td0
fcp 0 1/4/0/0.8 fcp CLAIMED INTERFACE FCP Protocol Adapter
ext_bus 7 1/4/0/0.8.0.255.0 fcpdev CLAIMED INTERFACE FCP Device
Interface
target 8 1/4/0/0.8.0.255.0.0 tgt CLAIMED DEVICE
disk 10 1/4/0/0.8.0.255.0.0.0 sdisk CLAIMED DEVICE HP 73.4GST373405FC
/dev/dsk/c7t0d0 /dev/rdsk/c7t0d0
target 9 1/4/0/0.8.0.255.0.1 tgt CLAIMED DEVICE
disk 11 1/4/0/0.8.0.255.0.1.0 sdisk CLAIMED DEVICE HP 73.4GST373405FC
/dev/dsk/c7t1d0 /dev/rdsk/c7t1d0
target 10 1/4/0/0.8.0.255.0.2 tgt CLAIMED DEVICE
disk 12 1/4/0/0.8.0.255.0.2.0 sdisk CLAIMED DEVICE HP 73.4GST373405FC
/dev/dsk/c7t2d0 /dev/rdsk/c7t2d0
target 11 1/4/0/0.8.0.255.0.3 tgt CLAIMED DEVICE
disk 13 1/4/0/0.8.0.255.0.3.0 sdisk CLAIMED DEVICE HP 73.4GST373307FC
/dev/dsk/c7t3d0 /dev/rdsk/c7t3d0
target 12 1/4/0/0.8.0.255.0.4 tgt CLAIMED DEVICE
disk 14 1/4/0/0.8.0.255.0.4.0 sdisk CLAIMED DEVICE HP 73.4GST373307FC
/dev/dsk/c7t4d0 /dev/rdsk/c7t4d0
target 13 1/4/0/0.8.0.255.0.5 tgt CLAIMED DEVICE
disk 15 1/4/0/0.8.0.255.0.5.0 sdisk CLAIMED DEVICE HP 73.4GST373405FC
/dev/dsk/c7t5d0 /dev/rdsk/c7t5d0
target 14 1/4/0/0.8.0.255.0.6 tgt CLAIMED DEVICE
disk 16 1/4/0/0.8.0.255.0.6.0 sdisk CLAIMED DEVICE HP 73.4GST373405FC
/dev/dsk/c7t6d0 /dev/rdsk/c7t6d0
target 15 1/4/0/0.8.0.255.0.7 tgt CLAIMED DEVICE
disk 17 1/4/0/0.8.0.255.0.7.0 sdisk CLAIMED DEVICE HP 73.4GST373405FC
/dev/dsk/c7t7d0 /dev/rdsk/c7t7d0
target 16 1/4/0/0.8.0.255.0.8 tgt CLAIMED DEVICE
disk 18 1/4/0/0.8.0.255.0.8.0 sdisk CLAIMED DEVICE HP 73.4GST373405FC
/dev/dsk/c7t8d0 /dev/rdsk/c7t8d0
target 17 1/4/0/0.8.0.255.0.9 tgt CLAIMED DEVICE
disk 19 1/4/0/0.8.0.255.0.9.0 sdisk CLAIMED DEVICE HP 73.4GST373307FC
/dev/dsk/c7t9d0 /dev/rdsk/c7t9d0
target 18 1/4/0/0.8.0.255.0.11 tgt CLAIMED DEVICE
disk 21 1/4/0/0.8.0.255.0.11.0 sdisk CLAIMED DEVICE HP 73.4GST373405FC
/dev/dsk/c7t11d0 /dev/rdsk/c7t11d0
target 22 1/4/0/0.8.0.255.0.12 tgt CLAIMED DEVICE
disk 22 1/4/0/0.8.0.255.0.12.0 sdisk CLAIMED DEVICE HP 36.4GST336753FC
/dev/dsk/c7t12d0 /dev/rdsk/c7t12d0
target 19 1/4/0/0.8.0.255.0.15 tgt CLAIMED DEVICE
ctl 7 1/4/0/0.8.0.255.0.15.0 sctl CLAIMED DEVICE HP A6255A
/dev/rscsi/c7t15d0
#

Maybe this will throw more light on the matter.

Also, I've looked at the document previously mentioned and tried using the JBODfmt command. The output of the JBODfmt command is as follows:

# JBODfmt -foverride /dev/dsk/c7t12d0
com.hp.HpPanDev.SanDevice.DeviceException: Failed to open device:null
# JBODfmt -foverride /dev/rdsk/c7t12d0
com.hp.HpPanDev.SanDevice.DeviceException: Failed to open device:null
#

Re: Can I convert 520 bytes per sector disks to 512 bytes per sector disk?

Torsten. — Thu, 29 Mar 2007 13:02:52 GMT

Hi,

I'm very sure the disks were attached to a VA74xx array.
The array is re-formating the disks to 520 blocks to store additional data.

With commandview you can format the disks back to 512 blocks.

Just run the GUI or cvui and select the format option.
(Make sure you have the needed java patches installed)

Re: Can I convert 520 bytes per sector disks to 512 bytes per sector disk?

goldboy — Thu, 29 Mar 2007 16:43:37 GMT

craig,
I have to agre with Patrik.
When I removed disks from the VA74xx (which formats them into 520 blocks) I run the followinf command:

JBODfmt -f /dev/dsk/cxtxdx

the command will format the disk back to 512 block size.

the command will only reside on a system that has Commandview installed on it.

any other attempt to format a disk using commandview SDM, cvui and such will result in formating the disk to 520 block size.

ofcourse the disk has to be in a JBOD that is directly conected to the system and not reside in the VA.

Tal

Re: Can I convert 520 bytes per sector disks to 512 bytes per sector disk?

Craig Stephens — Fri, 30 Mar 2007 02:57:44 GMT

Thanks guys.

I have been trying to use the JBODfmt command but the response is as follows:

# JBODfmt -foverride /dev/dsk/c7t12d0
com.hp.HpPanDev.SanDevice.DeviceException: Failed to open device:null
# JBODfmt -foverride /dev/rdsk/c7t12d0
com.hp.HpPanDev.SanDevice.DeviceException: Failed to open device:null
#

Any ideas?

Re: Can I convert 520 bytes per sector disks to 512 bytes per sector disk?

Marcel Burggraeve — Fri, 30 Mar 2007 03:21:23 GMT

When jbodfmt failed on me in the past ( on a HP-UX system ) out of curiosity we tried it on a DL380 running windows and it worked.
We just installed windows 2003 on the DL380, installed commandview on it and attached the DS2405 directly to the fibrecard in the system.
After that jbodfmt worked perfect from a dos box.

Re: Can I convert 520 bytes per sector disks to 512 bytes per sector disk?

Torsten. — Fri, 30 Mar 2007 03:34:29 GMT

As mentioned before:
http://h18012.www1.hp.com/java/patches/index.html

Re: Can I convert 520 bytes per sector disks to 512 bytes per sector disk?

Craig Stephens — Mon, 02 Apr 2007 02:52:30 GMT

I took Marcels advice ad it worked! Thanks for all of your help.

Re: Can I convert 520 bytes per sector disks to 512 bytes per sector disk?

arindamc — Wed, 14 May 2008 00:21:37 GMT

Hi,

I am using HP Storage 2405 with a disk model ST336607FC. I am getting the similar error "com.hp.HpPanDev.SanDevice.DeviceException: Failed to open device:" while formatting with JBODfmt. However i don;t have a DL380 option to try this on windows 2003. Is there any other way I can convert it to 512 bytes?

Thanks in advance for all response

Re: Can I convert 520 bytes per sector disks to 512 bytes per sector disk?

Mike.MA — Wed, 24 Feb 2010 22:17:30 GMT

use st from seagate to low-level format the disk to 512 bytes/sector.

Re: Can I convert 520 bytes per sector disks to 512 bytes per sector disk?

Andrew Davidson_3 — Thu, 15 Jul 2010 09:32:43 GMT

I'm getting the same error:

>JBODfmt -f /dev/dsk/c6t11d0
com.hp.HpPanDev.SanDevice.DeviceException: Failed to open device:null

I used this successfully in a similar situation in 2008 and am not clear what's needed to get it working now.

Andrew