Formatting Drives (Clearing Tru64)

[Paul Stanard]

My company is done testing the Alpha that I have been working on for the past month or so. We are planning to purchase a newer alpha (the one we rented is from production yr 1996) Does anyone know how to clear the OS from the drives? Any suggestions on the type of Alpha we should look into purchasing? I can give more details of the what we need to box to do if needed.

[Paul Stanard]

Would booting to the console..entering the AlphaBios Setup and deleting the partitions clear off all the data on the box

[Michael Schulte zur Sur · Accepted solution]

Hi Paul,

to wipe the machine clean, boot from installation cdrom, exit to shell and use
dd if=/dev/zero of=/devices/dsk/dsk0c bs=1024k

for all disks you have.
However, if you did not put any company data on it, why bother?

Michael

[Paul Stanard]

I put about 13Gb of company data on it last week

[Michael Schulte zur Sur]

Then use
showfdmn -k "datadomain"
where the data are and
use the dd command to erase them.
Run the dd command 5 times.

Michael

[Ravi_8]

Hi Paul

remove the vmunix and it's copies.

shutdown the machine, if the machine is booted again. system will not come up as there is no kernel file. when the user reinstall the OS all the data in the disk will be lost.

buy the latest model,
http://hp.com
look in servers link

[Eric van Dijken]

Ravi,

That would make the disk unbootable, but the data will still be there. You would only have to boot from an install cdrom. escape to the shell and you can access the data.

The "dd" method is a good one.

[Joris Denayer]

Maybe you can use the scu command to do a low-level format of the disk. Don't know if this works for HS[ZGV] connected disks.

Start from the installation CD
# dn_setup -boot
find the devicename of the disk to be cleared
# scu -f /dev/rdisk/dsk??c format

This should issue a "format pack" SCSI-command.

I don't know if this will be faster than the dd-trick.

Joris

[Ralf Puchner]

if the data is sensible, format drive with scu command or use dd to overwrite the data.

if there is no critical data on the drives, use dd write 1-2 MB to the partitions and clear the partitiontable.

[Joris Denayer]

Paul,

FWIW:
Formatting or overwriting is not bad to start with.
However, there will still leave remnants of magnetism that can be recovered with very specialised tools.
I heard that these remnants will be gone after ~35 overwritings.
US Department of Defense recommends 3 overwrites.

Of course, your mileage may vary.

Joris

[Paul Stanard]

Thanks for everyones advice. I will probably use the dd command several times

[Paul Stanard]

I booted the machine from the Installation disk and Exited the installer. I ran a showfdmn -k (usr_domain,data_domain) and the system can find neither domain. Was I supposed to issue those commands from the console prompt >>>?

[Joris Denayer]

Paul,

showfdmn looks in /etc/fdmns for the filedomainname that you specify.
When you boot from CD, /etc/fdmns certainly does't contain a directory usr_domain or root_domain. So, it will find anything at all.

Following procedure should work.

1) Boot your system from the original bootdisk
2) Run now the showfdmn commands for the specific domains
3) Note the device names on a paper ;-)
4) check with hwmgr the bus/target/lunnr of these devices (fi: hwmgr -view dev)
5) Boot from the cd and go in the administration shell
5) # dn_setup -boot (to create the devices)
6) Now search for the devices with the same Bus/Target/Lun combination
You can try following command
# file /dev/rdisk/dsk*c

7) When you have found the device, doublecheck with disklabel if this is really the correct one.

8) Now, you can do your dd wizardry

Joris

[Paul Stanard]

When u say the device names are you referring to the volume name ie /dev/disk/dsk5c for example

[Joris Denayer]

Paul,

Yes,

read 3 as follows
3) Note the volume names on a sheet of paper

Joris

[Paul Stanard]

How long does it usually take. It has been running for about an hour

[Joris Denayer]

Paul,

What is running for an hour ?

Joris

[Paul Stanard]

dd command on the disk that contains the data
dsk5h to be exact

[Paul Stanard]

usr_domain /dev/vol/rootdg/usrvol
root_domain /dev/vol/rootdg/rootvol

[Stephen A. Landers]

I have hundreds of Gbytes to overwrite on an array we are returning to the vendor. My servers report no /dev/zero file available when trying the dd command. How can I get past this obstacle or is there a better solution when we are trying to clear the disks and verify ourselves? Thanks

[Michael Schulte zur Sur]

Hi Stephen,

that's strange but you can recreate it with
cd /dev
./MAKEDEV zero

greetings,

Michael

[Stephen A. Landers]

/dev/zero(zero special file), which is known as source of zeros,
is available from HP-UX 10.30 and later. This functionality was
added to mm driver with major number 3 and minor number 4.

Note, on 10.30 and 11.00, /dev/zero is not created by insf(1m),
thus, system administrators need to create it with mknod command.
On 11.11 or later, insf creates /dev/zero automatically.

# mknod /dev/zero c 3 4 /dev/zero
# ls -l /dev/zero
crw-rw-rw- 1 bin sys 3 0x000004 May 2 2001 /dev/zero

This procedure helped a lot. The correction I would point out would be to omit the last /dev/zero in the mknod command.

I found that the procedure was successful with this implementation as shown below:

[sdat2c01][/] #date;od -c /dev/dsk/c4t3d0 | head -22
Thu Nov 11 13:17:49 EST 2004
0000000 \0 \0 \0 \0 \0 \0 \0 \0 \0 \0 \0 \0 \0 \0 \0 \0
*
0020000 L V M R E C 0 1 C h 245 3 @ m 017 271
0020020 \0 \0 \0 \0 \0 \0 \0 \0 \0 \0 214 237 \0 \0 \0 \0
0020040 \0 \0 \0 260 \0 \0 \0 200 \0 \0 \0 F \0 \0 \0 \n
0020060 \0 \0 \0 200 \0 \0 \0 330 \0 \0 \0 \b \0 \0 \0 320
0020100 \0 \0 001 ( \0 \0 200 \0 \0 \0 004 \0 \0 \0 \0 026
0020120 \0 \0 020 \0 \0 \0 \b 237 \0 \0 204 \0 \0 \0 \0 004
0020140 \0 \0 \0 \0 \0 \0 \0 \0 \0 \0 \0 \0 \0 \0 \0 \0
*
0022000 D E F E C T 0 1 \0 \0 \0 \0 \0 \0 \0 \0
0022020 \0 \0 \0 \0 \0 \0 \0 \0 \0 \0 \0 \0 \0 \0 \0 \0
*
0220000 L V M R E C 0 1 C h 245 3 @ m 017 271
0220020 \0 \0 \0 \0 \0 \0 \0 \0 \0 \0 214 237 \0 \0 \0 \0
0220040 \0 \0 \0 260 \0 \0 \0 200 \0 \0 \0 F \0 \0 \0 \n
0220060 \0 \0 \0 200 \0 \0 \0 330 \0 \0 \0 \b \0 \0 \0 320
0220100 \0 \0 001 ( \0 \0 200 \0 \0 \0 004 \0 \0 \0 \0 026
0220120 \0 \0 020 \0 \0 \0 \b 237 \0 \0 204 \0 \0 \0 \0 004
0220140 \0 \0 \0 \0 \0 \0 \0 \0 \0 \0 \0 \0 \0 \0 \0 \0
*
0222000 D E F E C T 0 1 \0 \0 \0 \0 \0 \0 \0 \0
[sdat2c01][/] #date;dd if=/dev/zero of=/dev/rdsk/c4t3d0;date
Thu Nov 11 13:18:42 EST 2004
I/O error
216001+0 records in
216000+1 records out
Thu Nov 11 13:22:50 EST 2004
[sdat2c01][/] #date;od -c /dev/dsk/c4t3d0 | head -22
Thu Nov 11 13:37:06 EST 2004
0000000 \0 \0 \0 \0 \0 \0 \0 \0 \0 \0 \0 \0 \0 \0 \0 \0
*
645700000
[sdat2c01][/] #

With /dev/null and other input files I tried to substitute, I experienced either a command lockup or 0 records in and 0 records out. I'm happy with the results. Thanks!