Hi all,

I am using ext3.... I want encryption of my harddisk in such a way that if someone take my harddisk and put it into their system as secondary device, they are not able to mount my harddisk.

So i just want to protect my data on the disk. So that no one can see my files by mounting my harddisk. So is there any utility available or any encryption method that will protect my data??

Any Input should be appreciable.

Hi.

This article is what your searching for:

http://www.linuxjournal.com/article/2590

Depends on your distro, kernel version. Too few info.
The link above works but there may be easier solutions

well, the linked article above is from 1998, there are some better solutions today
If you wanna encrypt your whole filesystem I'd recommend to use an encrypted lvm with (at least) 3 logical volumes (/, /home and swap). For encryption use dm_crypt. The debian installer offers this in it's partition dialog, certainly other distibutions have solutions as well.

You don't need to re-install linux of course. I have only my /home and swap encrypted and copied+symlinked /var and /tmp to /home. I'd suggest you read some tut's and then ask again if you have more specific questions.

Alternatives to dm_crypt would be truecrypt and loop-aes.

Just be aware that having an encrypted filesystem puts a burden on YOU, the user. You must enter a key every time you boot, and it's a good idea if that key isn't a trivial, easy to break key, such as your mother-in-law's birthday or your child's first and middle names. If you find some encryption that uses a dongle for the key, don't leave the dongle in the machine. It's an aggravation. If you're not up to the aggravation, then don't bother with encrypting your machine; instead, don't let anyone steal it in the first place.

Not entirely true. In the article below you have it described how to automatically mount an encrypted partition upon log in to X (without entering another password).

http://polishlinux.org/howtos/encryp...tion-in-linux/