CAE Linux on external USB disk

I just thought that I'd share my experience of getting CAE Linux to install on an USB external hard disk attached to a Sony Vaio laptop in case it proves useful to anyone else.

I must stress that I'm new to Linux so there is probably a better solution to the one that I arrived at but after much time spent with Google I must confess I couldn't find one.

1) ) Attach the USB disk (a Western Digital 400GB Passport in my case) and insert the LiveCD.

2) On startup enter BIOS and enable boot from external drive, also exclude internal drive from boot sequence and place USB device at the top. Save settings and restart allowing laptop to boot from CD.

3) When LiveCD has booted, login and then install PCLinux to USB drive. It seemed to matter that the OS went on to the first partition on the USB drive and the swap on to the second (sd1 and sdb5 in my case). - Use the custom option to do this.

4) Make sure GRUB gets loaded on to the USB drive otherwise the bootloader on the internal drive gets trashed and it won't boot without the USB drive.

5) Edit /boot/grub/menu.lst on the USB drive and replace references to sdb1 and sdb5 with sda1 and sda5 (in my case). Then edit /etc/fstab in a similar manner. This is important as otherwise when the laptop later tries to boot from the USB drive it swaps its sdb and sda references and because of this it can't find the files it needs to boot completely and you get a kernel panic.

6) Shutdown the laptop and remove the LiveCD.

The laptop should now boot from the external drive. To boot from the internal drive simply change the BIOS startup settings back to their original state. I also noticed that if I just swapped the boot order without excluding it the internal disk always took priority and the laptop would not boot from the USB device.

I hope this proves useful to someone.