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Restoring a differential or incremental backup

Regarding the two types of backups, assuming my HD crashed and I had a full plus 4 incremental backups.  To recover, would I restore the full backp then the 4 incrementals in order?

And if I had a Full backup and 4 differentials, would I restore the full first then just the last differential?

 

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Incremetals, pick the one you want and it will take care of the rest. No need to restore the full first. Just make sure you have all incrementals in the same folder and no missing pieces as all versions in the chain must be there (at least the ones prior) for the file you select.

Differentials, yes you just need the original full and any diff that correlates with that full.

There does seem to be a bug with rescue media on diffs if you don't have all of them. It may warn that it may not work if you don't, but it's worked for me in all my tests. We've submitted that this behavior should not occur since diffs do not rely on each other and only the full.

Bobbo,

I'm confused here. If I read your post precisely, it seems to say that if you have a differential chain, then to restore, you would first restore the full, and then in a second operation, restore the selected (usually last) differential on top of that. This is opposed to your description with an incremental chain where you describe just picking the desired incremental and allowing ATI to figure out how to do the complete restore.

I had occasion to have to restore my system disk recently. I worried about this very topic the OP raises. I took a chance and just told ATI recovery to restore the last differential of a multi differential instance chain. Somewhat to my surprise, ATI knew just what to do all by itself and restored using the full and that differential.

Sandy, when you do any Recovery (Restore) from a backup version chain, then you should only need to select the most recent file from the chain and then Acronis will follow the chain to recover all the related data needed from that chain.

With incremental chains, all the files for the chain need to be present for recovery to be successful as each file is dependent on the one before.

With differential chains, then ideally you should only need just the one Differential file plus the original Full backup file for a successful recovery.  Bobbo mentioned an issue discovered recently in the forums where any missing differential files will cause errors during recovery because for some reason Acronis has stored linked internally in these files referencing other files created within the chain!  The error messages are asking to locate the missing files but can be ignored repeatedly to achieve a successful recovery, albeit with potentially lots of annoying messages!  This does not happen if all the differential files are still present, even it all but one of these will be used!

Sandy, to clarify, as Steve mentioned, just pick the most recent backup in the chain and it does the rest. This is the same for diffs or incrementals.

The point I was trying to drive home is you need the files in a chain to all be there to work correctly (although, technically where an inch needs the entire chain, diffs really only require the original full and that one diff). People tend to want to manually move backup files or delete some manually (outside of Acronis) and that can cause issues when Acronis expects files that are no longer there after manual user intervention. 

 

Yeah, it works as I thought it did

Bobbo's post confused me a bit, but I figured it was just a wording problem. I wanted to make sure since when one (at least me) is in panic mode while doing a restore after a catastrophic system disk failure, I would hate to pick the wrong full or diff file and find I blew my only way home!

This post has cleared up some of my confusion, thanks!