this Hack I got from http://martin.hinner.info/ site. Martin is a Linux Guru Guru*
(Guru,Guru is one higher than just a plain Guru) I have my WD MyBook set-up in this configuration and it is has been an absolute lifesaver in times when I have been away from my media.
The process doesn't require hard drive dis assembly. It does not even require physical access to the drive. It works fine on every WD MyBook WE models (both I and II, capacities from 320GB to 2TB).
First of all you have to create a new user using standard web interface. SSH will not allow you to log-in as root without password.
Then enter this URL into your browser:
You should see a page that displays that "new firmware is available". (default username/password for MyBook is "admin"/"123456").
Click on "Click to download and install".
Now you have to be patient, the whole process will take a while - not 30 minutes as stated on the firmware upgrade page, because you are not actually performing any upgrade. The "upgrade" process will generate ssh host keys. This takes maybe 1 or 2 minutes. Then root's password is reset (set to '') and finally, sshd process is spawned.
Please note that you will not be informed about the operation progress. Just try to log in using ssh after a few minutes to see if it has succeeded. When you find out that sshd is running, log in under the user you created in the first step. You should get the bash shell immediately. Then type "su -" (no password) to get the root shell.
Making sshd permamentIn order to get ssh daemon running each time you power-up your MyBook, add the following line to /etc/inittab:
Now reboot your MyBook to see it if works.
Other recommendationsGet rid of mionet processes. as it allows "worldwide" data sharing, it's useless since you can install a web server or ftp server on your MyBook. Mionet is written in Java, which kills the arm processor on the mybook.
Consider also installing alternative web administration interface.