Clean confidential data from harddisk

kirukan · 01-21-2010, 03:49 AM

As i said in title, we need to erase all datas from harddisk before distroy our old servers.

Quote:

dd if=/dev/zero of=/dev/hda bs=1M

Quote:

shred -fzuv -n 100 /dev/hda

1. Which is the best practice to erase data, dd or shred?
2. How can i execute these commands in running server, do i need to re-boot the servers as RESCUE mode using bootable cd?

theboogymaster · 01-21-2010, 04:16 AM

Quote:

Originally Posted by kirukan

As i said in title, we need to erase all datas from harddisk before distroy our old servers.

1. Which is the best practice to erase data, dd or shred?

I think the best one is shred cause it will write the Hard Disck a lot of times and the data can't be read anymore.

Quote:

Originally Posted by kirukan

2. How can i execute these commands in running server, do i need to re-boot the servers as RESCUE mode using bootable cd?

Yes you need to mount the Hard Drive separatly.

jschiwal · 01-21-2010, 04:24 AM

Using a count of 100 is absurdly high. After 2 writes of random data, I doubt anyone will be able to read them.
I would recommend using DBAN to securely erase the disk drives.

Even better is to use a tool that uses a function in the drives themselves to do the same.
You could also take a drill and drill through the drives. Many modern drives have ceramic platters so a large hammer would word to smash the platters to bits.

kirukan · 01-21-2010, 07:12 AM

1. Can i do this task in RESCUE mode by booting bootable CD?
OR
2. Can i do this in single user mode?
we don't reuse this hardware, just only need to erase the data

linus72 · 01-21-2010, 07:24 AM

you can use a livecd
do you have one?

there are many apps for this, dd, dban, secure-delete wipe

I have most stuff like that on 503box-Chrome
http://linux.softpedia.com/get/Syste...86-53783.shtml

however, there are many linux livecd's for this
SystemRescueCD
DVL damn vulnerable linux

of course none of them have my eye-candy

google for the specific apps like dban, etc

H_TeXMeX_H · 01-21-2010, 08:19 AM

If you have a sledgehammer lying around and some safety goggles that will work fine too and it'll take less time. Thermite is also an option, as are large magnets.

kirukan · 01-21-2010, 08:23 AM

Can i use Knoppix for live CD?

jschiwal · 01-21-2010, 10:18 AM

Knoppix should be fine. As long as it's kernel has kernel modules for your disk controllers.

Quads · 01-21-2010, 01:14 PM

I don't know if you need the hard drives anymore, but if not when you get done erasing just drill holes through them.

kirukan · 01-21-2010, 09:49 PM

SunOS 5.8
#df -k ouput

Quote:

/dev/md/dsk/d10 /
/dev/md/dsk/d60 /in
/dev/md/dsk/d50 /indelivery
etc....

Quote:

#format
0. c1t0d0
1. c1t1d0
2. c1t2do
etc...

how can i identify which partition represent /in, /indelivary becasue its confusing me the two ouputs