My company had purchased a Pro Model hard disk duplicator a couple of years ago and has used it successfully until our disk drive vendor stopped production of the currently used drives and offered us what they considder to be a direct replacement drive.
On these new drives everything matches the old drives except for the drive sizes. the Old drives hold 18,353 KBytes and the new drives hold 18,211 KBytes. Because the new drives are smaller in size the mirror machine will not copy the drives.

Is there a way to copy the old drives to the new drives without having to format the drives;

1 without losing all the information on the disk ???
2 without re building the drives from nothing ???
3 without purchasing new drive ???

I was thinking maybe using the dd command.

We are using two Unix flavors
1 Sun Solaris (takes about 8 hours to format and partition)
2 HP-UX 10X

I appreciate any help that is offered

with a smaller size you also have a differant geomitry (if i am correct)

your only bet is to try the following:

1) toss the new drive the system adn set it up just liek the drive you want to mirror.
2) then try to mirror your production drive to the new drive.

dd is a low-level disk duplication utility, it copies byte-for-byte from input to output drive, so dd will not work. However, if you have more than 1 partition, you can use dd on the partition (i.e. not the entire drive @ once, just partition). This will be somewhat helpful, but then you are stuck with what do do with the last partition. If you have a swap partition that is among those to be mirrored, then you can just fdisk the destination drive, copy all partitions except the swap, and be done with it. Syntax will look like this for IDE:
dd if=/dev/hda1 of=/dev/hdb1
dd however is a very finicky system, you should only do it on UNMOUNTED drives! I cannot stress this enough. Other than that, you're stuck with formatting them and copying it manually with the cp -r command.

Options:
a)
With HP-UX in combination with MirrorDisk/UX you can mirror logical volumes to the other disk and later break the mirror.

b)
What and why do you want to format??
Do you use mediainit (hp-ux)?
anyway way don't do following:
Check the name of your disk special file:
ioscan -fnkC disk
pvcreate /dev/rdsk/c#t#d# (-B is disk must be bootable)
vgextend
lvcreate ...
mkdir and mount filesystems
========
cp -p -r sourcedir destdir
for each filesystem

If the disk needs to replace the bootable disk there is a lot more you should prepare with mkboot, setboot, lvlnboot commands
This whole procedure can best be looked up on the HP site.

Or even better
c)
Perform a restore, this is a good restore test.

Good luck
Rene