I'm working on a legacy project with a small single board computer running Ubuntu 10.04 on a compact flash card. I need to be able to save away a working image (via dd) and copy said image to other compact flash cards for use in other single board computers (with identical hardware)

I'm able to copy the image to other flash cards and bootup on other systems no problem. But I'm seeing strange behavior. For instance, I can't use sudo on the new system (“sudo: must be setuid root”). I've gone down the path of trying to fix this, but have run into a slew of other issues.

General question is: what do I need to be aware of when moving a hard disk containing Ubuntu (in my case a compact flash card) to another computer? I was hoping it would be seamless to Ubuntu since it's moving to a system with identical hardware. Is there something that needs to be done to make it "portable"?