Howto securely erase a harddrive .

Simply deleting, formating or zero writing a hard drive is not enough to keep a determined individual from restoring data from a hard drive. To ensure that your data really is deleted use a CD based distribution such as knoppix to boot the computer.

You can either issue the following commands seperated by a semicolon (;) or put them into a script. This is essentially a fire and forget process, but it will take a really long time.

Also, each pattern (writing 0’s, 1s, and random) should be done 4 to 8 times for maximum security.

I am just posting a few of those little usefull commands, links, and utils that make my digital life so much easier:

* What hardware have you got? What version is your BIOS? dmidecode is perfect for this. One that I use regularly is to check the BIOS version without rebooting.

 sudo dmidecode -s bios-version
This command returns something like this:
ASUS M2A-VM HDMI ACPI BIOS Revision 0502

* Check device usage
fuser (device)
eg:
 fuser /dev/dsp

used for finding out what software has control of a given device. Very usefull when tweaking and troubleshooting a linux pro audio set up.

* rsync backups
rsync -avzue ssh (username)@(hostname or ip):/(path to backup)/* (localpath )

This backs up all files and directories on the remote host and copies to the folder you specify.

* Hard Drive Tuning (Linux)
hdparm (options) (hard drive device) For example:
hdparm -c3 -d1 -S36 /dev/hda

This controls the hard drive, specifically I am enabling dma which speeds up the hard drive, setting i/o to mode 3 which also speeds things up.

I am working on a wireless security project, which involves bridging, routing, and packet filtering (but not NAT). As I was looking at my current default iptables rule set, I noticed that it could use some cleaning up.

This firewall script is designed for stand alone hosts that provide some services.

The script takes a single argument for the interface to run on, but will default to eth0 if you do nothing.


#!/bin/sh
# firewall-up.sh
#v3.07

if [ "$#" = "0" ]; then
EXT_INT="eth0"
exit 1
else
EXT_INT=$1
fi

PATH=/bin:/sbin:/usr/local/sbin/:/usr/sbin

Originally posted July 17th, 2007:

I have a Compaq Presario V3010CA which has a broadcomm wireless chipset. To be more precise lspci lists the particular card as:

Network controller: Broadcom Corporation Dell Wireless 1390 WLAN Mini-PCI Card (rev 01)

A friend gave me this amusing recipe, called “the Drunken Chicken”.

Take one rinsed and cleaned 3.5 lb. chicken and leave it out to dry, then dampen with a towel.

Next rub Vietnamese 5 spice all over it.

Make a mixture of: smashed garlic, coriander, vegetable oil, and 5 spice.

Spread inside chicken cavity, then very carefully rub it under the skin, directly on to the breast.

Open a can of beer (he suggested that we use Tiger Beer since this is an Asian recipe), then violate the chicken with the beer can (yes you read that right).

The chicken should be placed upright on a pie plate on the BBQ.

If using a gas BBQ then it should be cooked on low, with a charcoal BBQ wait until the briquettes are nice and hot (they should be gray).

Let this cook for about an hour.

A friend of the family let me in on a tasty little recipe for a mandarin orange cake. Enjoy.

* 2 c of flour
* 1.5 c of white sugar
* 2 t. baking soda
* 1 t. salt
* 2 eggs
* 2 cans of well drained mandarin oranges

Mix thoroughly! Put into a 9×13 inch oiled pan. Bake 30-40 minutes at 350 F.

Topping:

* 1 c brown sugar
* 0.25 c butter
* 0.25 c milk

Boil for 3 minutes. Poke holes in cake and pour over cake.