LinuxQuestions.org - External usb drive taking space on root fs?

[Hmm, I think I just posted this but it seems to have disappeared -- sorry if it's double posted.]

Hello,

First of all, I'm a newbie, so pardon my ignorance.

I'm trying to backup just my home directory onto an external usb hard drive. I don't need any fancy compression or anything, just a straight recursive copy of my home directory and all its subdirectories so that I can reinstall Ubuntu 5.10 Breezy (due to unresolvable ati graphics card issues with Ubuntu 6.06 -- see http://www.linuxquestions.org/questi...70#post2300170) and copy the contents back. I followed these instructions to create a filesystem on a brand new "Safe Store" 250 GB external usb drive.: http://www.thelinuxpimp.com/main/mod...rticle&sid=561. Now I have a nice filesystem mounted at /mnt/usbdrive/ and it seems that I can read + write to it fine.

To copy over my home, I did this:

Code:

sudo mkdir /mnt/usbdrive/backup

sudo cp -r /home/jeremy /mnt/usbdrive/backup

It seemed to be working slowly but surely (files were appearing in /mnt/usbdrive/backup), but then I got warnings that my memory was low, and when I used the System > Administration > System Monitor tool, I noticed that the memory on / was indeed being eaten away bit by bit (so to speak) as the the copy proceeded. I cancelled the copy and recursively removed /mnt/usbdrive/backup.

This doesn't make any sense to me. Isn't the whole point of an external drive that it doesn't take the space from your root filesystem? Are my method and/or understanding flawed?

Any help much appreciated.