Bootable backup partition size

Hi, i have bought a 1TB external hard drive and read online that you are best to create 2 separate backups incase one files and that the size of the space to leave for each should be atleast the size of the actual hard drive.

My hard drive is 250GB but when i completed one bootable backup the size was only 50GB. I would rather not waste my drive space so could i start from scratch and leave say 100GB space for each partitioned bootable backup?

Thanks, Wix

Are you never going to have more than about 80GB of data on your internal 250GB hard drive? The answer is, no one knows, not even you. I would suggest your bootable backup partition remains at the same size as your internal drive at 250GB.

This is not wasted space. At a cost of less than $100 for a 1TB external drive today, you are spending less than $25 for a bootable backup - better way to look at it.

If you are creating 2 bootable backups onto the same hard drive - I would quit doing that and save that 250GB for other data storage or be using it for a Time MAchine backup instead. If the drive dies, you will lose both of the backups. There really is not a lot of point in having multiple backups on the same drive.

And remember, an untested bootable backup is no backup at all. You should boot to your backup drive on occasion to make sure it is a copy and works / functions like your internal drive - albeit maybe a little slower.

OK, great, cheers for your advice - i do have a separate external hard drive so i will back the 2nd up to that. I am still on Tiger and dont have Time machine so i will persist with Superduper. Thanks again.