OK. I'll concede that one. I have written myself a memo saying, "Do not copy other peoples' commands until you understand them." If a disk clone is being created then the obvious requirement is that it should fail if an error occurs. I did not at first realize that this is the 'dd' default - but I do now. The best I can claim in my defence is that I am learning from my mistakes. I still find it paradoxical, however, that, if the conv=noerror parameter is used, it causes a fatal error in the cloning process.

Well, maybe I'm just a lazy cloner at heart. If something goes really amiss I can simply exchange the main hard disk for a clone. If I just want a file or two I can connect the caddy, mount the clone and find the required item(s) in exactly the same place as on the main disk. If, as I earlier conceded, you measure your disk sizes in terabytes then you will probably see things differently but cloning an 80GB disk now only takes 45 minutes, yielding a 'push-button' recovery facility. Maybe I have too many memories of being confronted by the infamous BSOD (blue screen of death, as it was known) and then having to embark on a tedious differential recovery. I am also not too comfortable with that word 'almost' .

Ooh! I had a quick look at the syntax and got an instant attack of 'newbie's indigestion'.

I'll tell you what; if you would like to try it first, contrasting it with straight 'dd', then I would be very interested in your results.

But you have to spot the problem before the next daily(?) backup.
With differential backups I can afford to be more lackadaisical.

BTW If you have to replace your 80GB drive with another, you will not find it easy.

I have three 80GB disks in caddies that I cycle, enabling me to be a bit lackadaisical, even if not so much as you.

Well it shouldn't be difficult if it's one of the clones. I'll just replace that with another blank 80GB disk which I then introduce into the clone carrousel. If it's a bigger disk then I'll just copy my files - like you do! . Although, come to think of it, surely I will be able to clone one of my 80GB disks to a larger one? I can't imagine going back to a smaller one.

Time to declare a draw, do you think.

My PC has 2 x 1TB disks + 750GB NAS-attached offline storage(1) + 2TB USB-attachable offline storage(2).
Plus I run occasional backups using ssh & rsync to a netbook.

You might find products such as Spider Oak useful for storing a few bytes "in the cloud".