dd as a disk wiper ? with advanced options ?

raven4d · 06-07-2013, 07:55 PM

hello , i know this might sound strange , but i need to wipe some sectors every "some sectors"

so if a drive have 1000000000 LBAs
i want to wipe 2 sectors every 10 sectors and so on ...

dd if=/dev/zero of=/dev/sda bs=1024

the upper command should wipe 2 sectors of the selected devise , but how to make it jump over 10 LBAs and write two zero sectors again ? adding seek=5120 ?!?!

thank you

Ser Olmy · 06-07-2013, 08:25 PM

You could use a simple for loop:

Code:

for ((i=0 ; i<1000000000 ; i=i+10)); do dd if=/dev/zero of=/dev/sda seek=$i bs=512 count=2 ; done

Neither dd nor dcfldd seem to have a switch to write to every n sectors(s).

raven4d · 06-08-2013, 03:04 AM

thank you very much sir ;

so i should do a script to do the task ..

excuse my low scripting knowledges but i will write down the script and thank you for our notices .

****************************************
#bin/sh
for ((i=0 ; i<1000000000 ; i=i+10)); do dd if=/dev/zero of=/dev/sda seek=$i bs=512 count=2 ;
done ;
****************************************

then i have to do chmod+x script and just excute it , right ?

thank you again