topic Re: Formatting Drives (Clearing Tru64) in Operating System - Tru64 Unix

Formatting Drives (Clearing Tru64)

Paul Stanard — Mon, 08 Mar 2004 11:20:55 GMT

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.

Re: Formatting Drives (Clearing Tru64)

Paul Stanard — Mon, 08 Mar 2004 11:26:46 GMT

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

Re: Formatting Drives (Clearing Tru64)

Michael Schulte zur Sur — Mon, 08 Mar 2004 11:33:08 GMT

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

Re: Formatting Drives (Clearing Tru64)

Paul Stanard — Mon, 08 Mar 2004 11:34:48 GMT

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

Re: Formatting Drives (Clearing Tru64)

Michael Schulte zur Sur — Mon, 08 Mar 2004 12:37:39 GMT

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

Michael

Re: Formatting Drives (Clearing Tru64)

Ravi_8 — Tue, 09 Mar 2004 00:14:07 GMT

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

Re: Formatting Drives (Clearing Tru64)

Eric van Dijken — Tue, 09 Mar 2004 01:34:15 GMT

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.

Re: Formatting Drives (Clearing Tru64)

Joris Denayer — Tue, 09 Mar 2004 02:29:24 GMT

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

Re: Formatting Drives (Clearing Tru64)

Ralf Puchner — Tue, 09 Mar 2004 02:53:10 GMT

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.

Re: Formatting Drives (Clearing Tru64)

Joris Denayer — Tue, 09 Mar 2004 03:06:13 GMT

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

Re: Formatting Drives (Clearing Tru64)

Paul Stanard — Tue, 09 Mar 2004 08:01:38 GMT

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

Re: Formatting Drives (Clearing Tru64)

Paul Stanard — Wed, 10 Mar 2004 10:49:19 GMT

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 >>>?

Re: Formatting Drives (Clearing Tru64)

Joris Denayer — Wed, 10 Mar 2004 11:01:28 GMT

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

Re: Formatting Drives (Clearing Tru64)

Paul Stanard — Wed, 10 Mar 2004 11:45:32 GMT

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

Re: Formatting Drives (Clearing Tru64)

Joris Denayer — Wed, 10 Mar 2004 11:49:00 GMT

Paul,

Yes,

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

Joris

Re: Formatting Drives (Clearing Tru64)

Paul Stanard — Wed, 10 Mar 2004 14:02:06 GMT

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

Re: Formatting Drives (Clearing Tru64)

Joris Denayer — Wed, 10 Mar 2004 14:18:04 GMT

Paul,

What is running for an hour ?

Joris

Re: Formatting Drives (Clearing Tru64)

Paul Stanard — Wed, 10 Mar 2004 14:21:17 GMT

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

Re: Formatting Drives (Clearing Tru64)

Paul Stanard — Wed, 10 Mar 2004 14:27:43 GMT

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

Re: Formatting Drives (Clearing Tru64)

Stephen A. Landers — Thu, 11 Nov 2004 11:05:35 GMT

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