What happens when you do a sector-by-sector copy to a smaller hard drive?

[fwacct4]

<See title>

 

[hanspeter]

If the earth was actually flat, you would eventually drop off if you continued. Something like that maybe

 

[dunkster]

Check description of capabilities for the drive utility offered by the maker of the drive.

I've used drive utilities from both WD and Maxtor that offer the choice to automatically scale partition-size(s) or allow manual partition-size assignment prior to actual cloning operation. In those instances, I was cloning a multi-partition drive.

Paid partition-managers (Paragon, for example) offer same options.

Hope this helps!

 

[Nothinman]

What happens when you do a sector-by-sector copy to a smaller hard drive?

If the imaging software lets you do it, which it shouldn't, it'll fail when it gets to the end of the target drive.

 

[dunkster]

There are two methods of sector-copying:
- Copying only used sectors (empty sectors are ignored).
- Raw sector-by-sector copies every sector serially, including empty sectors.

The copy-only-used-sectors method will allow copying any partition to another partition, so long as there is sufficient free space in the target partition. This method (copy-only-used-sectors) would make it quite possible to copy partitions from, for example, a 500GB drive to a 250GB drive so long as there is sufficient free space in each target partition.

That is the method used by the WD and Maxtor utilities I used for (40GB IDE to 80GB IDE) multi-partition drive cloning. That was some time ago, and I don't know if the same capabilities are offered in current utilities by HD vendors.

I periodically clone a Seagate 250GB to a WD 250GB drive by the raw-sector-by-sector cloning method to create an emergency swap drive. If I were to use raw-sector-by-sector copy method to an empty 500GB drive, the larger target drive would be left with approximately 250GB of unpartitioned space. That unpartitioned space could be easily reclaimed with partition-management software by expanding existing partition-sizes or simply creating another partition.

These methods are available in partition-management apps offered by Acronis, Paragon and Easeus.

Hope this helps!

 

[fwacct4]

Originally posted by: dunkster
There are two methods of sector-copying:
- Copying only used sectors (empty sectors are ignored).
- Raw sector-by-sector copies every sector serially, including empty sectors.

The copy-only-used-sectors method will allow copying any partition to another partition, so long as there is sufficient free space in the target partition. This method (copy-only-used-sectors) would make it quite possible to copy partitions from, for example, a 500GB drive to a 250GB drive so long as there is sufficient free space in each target partition.

That is the method used by the WD and Maxtor utilities I used for (40GB IDE to 80GB IDE) multi-partition drive cloning. That was some time ago, and I don't know if the same capabilities are offered in current utilities by HD vendors.

I periodically clone a Seagate 250GB to a WD 250GB drive by the raw-sector-by-sector cloning method to create an emergency swap drive. If I were to use raw-sector-by-sector copy method to an empty 500GB drive, the larger target drive would be left with approximately 250GB of unpartitioned space. That unpartitioned space could be easily reclaimed with partition-management software by expanding existing partition-sizes or simply creating another partition.

These methods are available in partition-management apps offered by Acronis, Paragon and Easeus.

Hope this helps!

Thanks. That helps a lot. I used a bootable CD of CopyWipe v1.14 to clone a 320GB Maxtor to a Hitachi.

When I tried the smart copy with proportional partitioning option, my Vista64 needed a bootfix to make it work ok.

But when I used the raw sector-by-sector copy, the copying result was perfect.

Tech support said they haven't updated the software to take into account vista64, so I was wondering what the results would be in using sector-by-sector copying into larger or smaller drives since for Vista 64 in many cases, sector-by-sector copying is the only method that works without a hitch.

 

[dunkster]

When I tried the smart copy with proportional partitioning option, my Vista64 needed a bootfix to make it work ok

That's a potential problem in the copy-only-used-sectors method. Some copy apps may, for example, interpret a sector as 'empty' when it actually contains an encrypted password.

The raw-sector-by-sector copy method is preferred, since it serially copies every sector without exception.

Hope this helps!

 

[Nothinman]

That's a potential problem in the copy-only-used-sectors method. Some copy apps may, for example, interpret a sector as 'empty' when it actually contains an encrypted password.

That makes no sense at all, either a sector is used or not and the filesystem marks it as such. There's no inbetween unless the filesystem needs chkdsk, fsck, etc run on it.

 

[fwacct4]

Originally posted by: Nothinman

That's a potential problem in the copy-only-used-sectors method. Some copy apps may, for example, interpret a sector as 'empty' when it actually contains an encrypted password.

That makes no sense at all, either a sector is used or not and the filesystem marks it as such. There's no inbetween unless the filesystem needs chkdsk, fsck, etc run on it.

Regardless, these types of smart sector copies don't seem to get it right for Vista64 as I experienced. Whether dunkster's explanation is 100% or not, the problem exists. I don't know what's causing it, but it would be nice to know since that would give some of us a clue as to how these smart sector copy functions work and why they need to be updated to fully take into account Vista64.

 

[Nothinman]

Regardless, these types of smart sector copies don't seem to get it right for Vista64 as I experienced. Whether dunkster's explanation is 100% or not, the problem exists. I don't know what's causing it, but it would be nice to know since that would give some of us a clue as to how these smart sector copy functions work and why they need to be updated to fully take into account Vista64.

They work because they know how the filesystem works. They either include a filesystem driver so whenever changes to the filesystem happen the driver needs update to support the new layout. At this point the layout of NTFS is pretty stable and I don't think MS made any major changes when they released Vista so I have no idea what problems you're talking about.

 

[taltamir]

Originally posted by: Nothinman

What happens when you do a sector-by-sector copy to a smaller hard drive?

If the imaging software lets you do it, which it shouldn't, it'll fail when it gets to the end of the target drive.

the right answer, there is nothing more to say. it WILL refuse to do so... or if it is a crappy utility it will fail.