Sponsored Content
Special Forums Hardware Filesystems, Disks and Memory Erasing hard disk contents using dd or dcfldd Post 302323126 by jake24 on Friday 5th of June 2009 01:02:54 PM
Old 06-05-2009
Thanks everyone for the responses.
Actually my doubt is if I am doing 2 swipes over the disk with a pattern and its compliment, using either dd/dcfldd for the purpose in a script, then the first swipe should have actually ended up physically on the sectors on disk before the second swipe.
With the script I have pasted in my first post, is the sync in between 2 swipes sufficient to ensure that?
Can anyone help me with some pointers on the impact of OS/disk caches on the way to disk sectors?
 

10 More Discussions You Might Find Interesting

1. Filesystems, Disks and Memory

hard disk meltdown

I had an issue with a second hard disk in my machine. I have a sparc station running solaris 7. It was working fine but now it wont mount on boot up and when you try to mount it manually it gives an I/O error. I tried a different disk as a control which was fine. What I want to know is if my... (3 Replies)
Discussion started by: Henrik
3 Replies

2. UNIX for Dummies Questions & Answers

How to Copy Contents from CD to Hard disk

Hello all.. Iam New to Unix Environment. I need to copy .cpio file from CD to a Folder on Sun 5.8 Box. Can anyone give me the commands to execute this ?.. Thanks in advance Ron (4 Replies)
Discussion started by: vr76413
4 Replies

3. UNIX Desktop Questions & Answers

Hard Disk

I have a cuestion. How Can I to add other hard disk to my computer? I need to configurate anyone? (4 Replies)
Discussion started by: hmaraver
4 Replies

4. UNIX for Dummies Questions & Answers

Hard Disk at 99% Help!

:eek: I use this Solaris to run CMS a call acounting software package for my job. No one could run reports today because it said the this when you logged on "The following file systems are low, and could adversely affect server performance: File system /: 99%full" Can some one please explain... (9 Replies)
Discussion started by: mannyisme
9 Replies

5. SCO

declare disk driver for IDE hard disk

hi I've a fresh installation of SCO 5.0.7 on the IDE hard disk. For SCSI hard disk I can declare, for example blc disk driver using: # mkdev hd 0 SCSI-0 0 blc 0but it works for IDE hard disk? (3 Replies)
Discussion started by: ccc
3 Replies

6. Solaris

Need Hard Disk Details

Hi freinds, What is the command to find out the hard disk details (logical name, FS type etc,). Because i connected one ntfs partition and i don't know the hard disk logical and physical name to mount it.Kindly do the needful. Thanks | P.Bharathiraja. :mad: (2 Replies)
Discussion started by: bharathiraja
2 Replies

7. Red Hat

Need help for getting hard-disk traces

When we write a programme,we declare variables and compiler allocates memory to them.I want to get access to the physical block number of hard-disk where actually the data is stored by the programme " Some one help me out... (1 Reply)
Discussion started by: nagraz007
1 Replies

8. UNIX for Advanced & Expert Users

Need help for getting hard-disk traces

When we write a programme,we declare variables and compiler allocates memory to them.I want to get access to the physical block number of hard-disk where actually the data is stored by the programme " Some one help me out... (3 Replies)
Discussion started by: nagraz007
3 Replies

9. Linux

C++ Code to Access Linux Hard Disk Sectors (with a LoopBack Virtual Hard Disk)

Hi all, I'm kind of new to programming in Linux & c/c++. I'm currently writing a FileManager using Ubuntu Linux(10.10) for Learning Purposes. I've got started on this project by creating a loopback device to be used as my virtual hard disk. After creating the loop back hard disk and mounting it... (23 Replies)
Discussion started by: shen747
23 Replies

10. BSD

Migrate a Hard Disk

hi Has anyone already tried to migrate a hard disk with FreeBSD using recoverdisk? (1 Reply)
Discussion started by: ccc
1 Replies
DISKTAB(5)						      BSD File Formats Manual							DISKTAB(5)

NAME
disktab -- disk description file SYNOPSIS
#include <disklabel.h> DESCRIPTION
Disktab is a simple database which describes disk geometries and disk partition characteristics. It is used to initialize the disk label on the disk. The format is patterned after the termcap(5) terminal data base. Entries in disktab consist of a number of `:'-separated fields. The first field for each entry gives the names by which a disk's entry may be selected, separated by `|' characters. The last name given should be a long name fully identifying the disk. The optional fields for each entry are: ID Type Description ty str Type of disk (e.g. removable, winchester) dt str Type of controller (e.g. SMD, ESDI, floppy) ns num Number of sectors per track nt num Number of tracks per cylinder nc num Total number of cylinders on the disk sc num Number of sectors per cylinder, ns*nt default su num Number of sectors per unit, sc*nc default se num Sector size in bytes, DEV_BSIZE default sf bool Controller supports bad144-style bad sector forwarding rm num Rotation speed, rpm, 3600 default sk num Sector skew per track, default 0 cs num Sector skew per cylinder, default 0 hs num Headswitch time, usec, default 0 ts num One-cylinder seek time, usec, default 0 il num Sector interleave (n:1), 1 default d[0-4] num Drive-type-dependent parameters bs num Boot block size, default BBSIZE sb num Superblock size, default 0 ba num Block size for partition `a' (bytes) bd num Block size for partition `d' (bytes) be num Block size for partition `e' (bytes) bf num Block size for partition `f' (bytes) bg num Block size for partition `g' (bytes) bh num Block size for partition `h' (bytes) fa num Fragment size for partition `a' (bytes) fd num Fragment size for partition `d' (bytes) fe num Fragment size for partition `e' (bytes) ff num Fragment size for partition `f' (bytes) fg num Fragment size for partition `g' (bytes) fh num Fragment size for partition `h' (bytes) oa num Offset of partition `a' in sectors ob num Offset of partition `b' in sectors oc num Offset of partition `c' in sectors od num Offset of partition `d' in sectors oe num Offset of partition `e' in sectors of num Offset of partition `f' in sectors og num Offset of partition `g' in sectors oh num Offset of partition `h' in sectors pa num Size of partition `a' in sectors pb num Size of partition `b' in sectors pc num Size of partition `c' in sectors pd num Size of partition `d' in sectors pe num Size of partition `e' in sectors pf num Size of partition `f' in sectors pg num Size of partition `g' in sectors ph num Size of partition `h' in sectors ta str Partition type of partition `a' (4.2BSD file system, swap, etc) tb str Partition type of partition `b' tc str Partition type of partition `c' td str Partition type of partition `d' te str Partition type of partition `e' tf str Partition type of partition `f' tg str Partition type of partition `g' th str Partition type of partition `h' FILES
/etc/disktab SEE ALSO
getdiskbyname(3), bsdlabel(8), newfs(8) HISTORY
The disktab description file appeared in 4.2BSD. BSD
October 14, 2006 BSD
All times are GMT -4. The time now is 05:07 AM.
Unix & Linux Forums Content Copyright 1993-2022. All Rights Reserved.
Privacy Policy