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Cloning vs Disk/Partition Backup with and without Sector by Sector option

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Is it true that unless you either 1) Clone a disk, or 2) Backup up a disk **with sector-by-sector slected** under Image Creation Mode , then you are **NOT** going to have any boot information backed up?

If so, it seems odd that in order to get a "True Image", one has to enable a checkbox under an advanced options tab.

Here's what got me thinking about this:

A recent Acronis newsletter (advertisement) inlcuded a link to an article about Cloning.  In it, it compared Cloning vs Backup.  In particular, it says:

Use backup software when you want to:

  • Back up an entire computer periodically. The disk-image backup includes all boot information, applications, settings, and data and stores all of it to a local, external hard drive or the cloud. When data and applications change, the backup software saves these “incremental” changes. Incremental backups take significantly less time than a new backup (or disk image) of an entire source drive. And, it allows you to recover everything that has happened since the hard disk was first set up.

This implies that using backup software (for example, selecting Backup - Disk in the True Image software) is the same as creating a disk image. 

The same article links to another article specifcally on "Imaging Software".

That article includes this sentence: 

"A disk image is a complete sector-by-sector copy of everything on your computer or external hard drive; completely capturing all files on your system and faithfully replicating all your data. With full-image backup you protect everything, including boot information, the operation system, settings, and data."

Note that it says sector-by-sector, implying that in order to "protect everything including boot information", you need to select a sector-by-sector option.  But that option is not the default, and the help files says that selecting it may increase backup time and result in larger backup files.

After previous interpretations of the documentation and chats with support, I currently do the following: 

In the True Image software, I add a backup, then select Disks and Partitions, select a disk, change the Backup Scheme to Singer Version, and accept the other defaults.  Note that the default does NOT include sector-by-sector under Image Creation Mode.

So, is what I'm doing (not selecting sector-by-sector) backing up boot information or not? 

Thanks for any clarifications.  


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David, welcome to these user forums.

Cloning and Backup & Restore can both achieve the same result and there is no need to use sector-by-sector when doing this - in fact doing so will complicate these actions by requiring that the target drive for the clone or restore must then be equal to or greater in size than the source drive.

All ATIH actions work on a sector basis, so in the article you have been reading this is not implying the same as using the actual sector-by-sector setting that is found in the Advanced configuration page settings.  The default action by ATIH is to copy only those sectors which are used to contain data, whereas when you choose to use sector-by-sector mode all sectors on the source drive are copied, including all unused sectors.  ATIH will switch over to using sector-by-sector in the event that a disk failure or bad sector(s) are encountered, and the resultant backup image size will be significantly larger because of this.

When you make either a Clone or a full disk Backup image, then you will get all the data required to write to a new disk drive and for that drive to be bootable into the Windows OS that the source drive used.

From a MVP perspective, we would always recommend doing Backup & Restore in preference to using Cloning, and would always recommend (strongly) that a full Backup is taken even when using Cloning.  Both can and do achieve the same end result if performed correctly, but Backup is 100% safer because you do not involve the source drive in the actions to write the data to the new drive, whereas with a clone, both drives are involved and any problems that arise can lead to the damage or corruption of both drives (and does so, as evidenced by some of the user topics posted in these forums by users who have got this wrong!).

Lastly, a Backup image can be used multiple times over as needed.  A Clone is a one-off action that puts both drives at risk when it is executed.

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David Mikelson wrote:
Is it true that unless you either 1) Clone a disk, or 2) Backup up a disk **with sector-by-sector slected** under Image Creation Mode , then you are **NOT** going to have any boot information backed up?

No. This is absolutely false.

Steve has explained it well, but I just wanted to add a short, clear statement that your supposition is wrong. I don't know why you would think that. It would be useful for you to read the manual and check out some of the user guides linked from the left margin of this forum.

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Thanks for the quick reply.  I just wanted to be 100% sure.  

In some Acronis documents, the word "data" apparently means not only things like user documents, but also boot information.  And in others, the word data is used as well as the term "boot information", implying the writers of those  particular documents somehow consider "data" and "boot information" different things.

But you have made that clear now, and thanks for the clear recommendation regarding the Image Creation Mode settings.

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David, you are welcome.

See also KB documents: 1540: Difference between Backup and Disk Clone and 56634: Acronis True Image: Cloning Disks as these will give you a lot more detailed information about these processes plus include video tutorials.

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1. If I wanted to do a clone "sector by sector" for some reason, how do I do that?

2. On some occasions, when doing a clone (from the operating disk, so Acronis has to operate in a "system restart" mode), Acronis will do the clone in a way that takes over twice as long as usual. I suspect it may be working in the "sector by sector" fashion. What might cause this?

Might this be caused by the discovery of file system anomalies in the source disk (the kind of thing ChkDsk is supposed to find and clear up)?


Doug Kerr

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Doug, welcome to these public User Forums.

There are no options to specify to use sector-by-sector mode in the Clone wizard settings that I can see, but Acronis will default to using that mode if there are any file system issues encountered, i.e. an unsupported (non-windows) file system format or bad sectors etc.

It is recommended that your should run CHKDSK against both drives before using cloning.

If you use Backup & Recovery instead of using Cloning, then you can elect to use sector by sector mode when creating the backup image and this will be recovered using the same mode to the new drive.

Normally, there are no advantages in using sector by sector mode unless you are looking at a forensic type issue, but even then it is not guaranteed to preserve all the contents of currently unused sectors that may contain previously deleted data.