billdotson
August 25th, 2009, 06:57 AM
By reading the g4u (ghost 4 unix) documentation/FAQs I found out that you don't HAVE to have the size of your image backup be the same size as the disk or partition you are copying. How do you do this you say? Well, write zeros to the empty space of your partition! The author said that g4u doesn't understand different filesystem types because it reads data at a lower level than a filesystem. Therefore, to write zeros to a partition or a drive you can use an operating system you want to clone to do the filesystem specifics for you.
One example that was given was to open a text file and fill it with 0s until the partition ran out of space then save it. After backing up the image you could compress it and voila, the zeros or "empty space" would be compressed down to a very small size. He also mentioned some special Windows programs to do this and the use of dd and /dev/zero.
However, I have some questions: if you wanted to write zeros to all the empty space on a partition how would you find out where to start? You certainly couldn't just pick byte 12848471253 and have dd start churning away without messing something up..
Also, MS is being really nice about Vista and have made it so that the second service pack won't install if "third-party disk management tools" are used. I don't know how but they made it so that cloned images of Vista wouldn't contain the right system files or the updater would not recognize them. If you used dd or g4u to make a low level partition or drive backup of a Vista install wouldn't that be a way around that?
G4u sounds like it copies data at the hardware level and I am almost certain that that is what dd does, so aren't they basically the same thing?
One example that was given was to open a text file and fill it with 0s until the partition ran out of space then save it. After backing up the image you could compress it and voila, the zeros or "empty space" would be compressed down to a very small size. He also mentioned some special Windows programs to do this and the use of dd and /dev/zero.
However, I have some questions: if you wanted to write zeros to all the empty space on a partition how would you find out where to start? You certainly couldn't just pick byte 12848471253 and have dd start churning away without messing something up..
Also, MS is being really nice about Vista and have made it so that the second service pack won't install if "third-party disk management tools" are used. I don't know how but they made it so that cloned images of Vista wouldn't contain the right system files or the updater would not recognize them. If you used dd or g4u to make a low level partition or drive backup of a Vista install wouldn't that be a way around that?
G4u sounds like it copies data at the hardware level and I am almost certain that that is what dd does, so aren't they basically the same thing?