Problem restoring using time machine

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Problem restoring using time machine

I am trying to restore an external drive with about 782 gig of data on it from a 2 terabit time capsule using time machine to a new external drive. I am using Yosemite on a three year old macbook pro. The first time I tried to do a full restore of the content of the original external drive that was backed up on the time capsule, it was restoring for a few hours, then came up with an error, stopped the restore without having saved anything. I then opted to go into the drive in the time capsule and highlight all the folders that were on the drive and restore that way. That seemed to work, except the restored drive has 50 GB less data than the original.

I really don't want to try to do a full restore again because it says it needs to erase the content of the new external hard drive and start over. The restore took something like 15 hours. My new drive is formatted correctly and I didn't exclude anything from being restored in the Time Machine settings.

I was hoping if i tried to restore the folders again that i'd get one of the messages that these files exist, do you want to replace them. I did get one of those messages but it said the folder exist, did I want to replace it, so that didn't really help as all the folders are showing up on the new external drive, but I'm short 50 gig of content inside those folders

Is there a way I can figure out what didn't get backed up?
Why does the entire restore seem to stop when it hits one troubled file?
Any other suggestions on how I can get my data back?

Mac OS X (10.4.2)

Posted on Nov 23, 2015 5:24 AM

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Answer 1

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LaPastenague

Level 9

67,208 points

Nov 23, 2015 1:57 PM in response to abdroma13

Is there a way I can figure out what didn't get backed up?

Only if you have the original disk... and then can do a compare.

Since you are going to great effort to recover I am guessing the original disk is not available.

Why does the entire restore seem to stop when it hits one troubled file?

Because that is how apple designed TM.. It is the wrong software to backup your external drive to be honest.

You can run a verify of the TM backup. See A5 here. http://pondini.org/TM/Troubleshooting.html

That should repair any faults in the backup.

Any other suggestions on how I can get my data back?

If you don't know what is missing then how do you know if it is recovered??

Are you absolutely sure the original disk size showed 782GB and are you sure they are binary bytes or digital bytes..

Where do the numbers come from?

What OS are you running? Your profile is showing 10.4 which I doubt is current.

50GB is meaningless.. unless you use the same measurement method.

50GB is meaningless unless it is measuring the files on the same disk as originally used.

Let me explain.

Problem 1.

Files are not using 100% of sectors on the disk.. if you use a different disk with different sector sizes.. the same files copied onto two different disks occupy different amount of disk space.. because sectors cannot be filled 100%.

So the file above is 73.3MB and it occupies 73.4MB on disk. That means this particular file used up more disk space.. by 0.1MB

But here is a small file.

The file is only 857bytes.. but it occupied 4KB on disk.. because this disk is using 4K sectors. If your backup includes lots of small files.. your size on disk for the backup will be different on disks of different sector sizes..

And there are changes in sector sizes between smaller and larger drives.

Problem 2.

Apple have made a change that is confusing.. Hard disks are measured in digital bytes.. to make the numbers look big.

Of course files are binary.. and bytes are not digital... so if you look at the size of a formatted disk it is different to the disk size in digital.

So.. I have a 2TB Time Capsule.

In v6 airport utility it shows

In the old utility it shows

The drive when newly formatted shows 2TB capacity in v6 utility and 1.8TB in v6.

I have 179.7GB of data on it according to v5 utility. And there is 1.6TB space left.

According to v6 utility I have 1.8TB space left.

That is because old utility uses binary bytes.. and new utility uses digital bytes.

So are you comparing binary to digital.. it could easily vary by 50GB.

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