Never-ending file transfer

[Brookzy]

Has anyone seen this before?

I'm trying to transfer my iMac's Time Machine backups from my old Seagate hard drive to my new LaCie d2 Thunderbolt 3.

The old hard drive has a 1TB partition for the backups, and there is about 850GB of data on it.

Yet when transferring it to the new drive, the transfer continues seemingly forever, like this:

The amount of data just keeps rising and rising with the "about 5 seconds" estimate remaining for hours.

It shouldn't be possible to have that much data when the source disk is only 1TB.

What's going on? I've tried reformatting and trying again; the same thing happens.

 

[BrianBaughn]

Are you following this procedure?

 

[Brookzy]

Are you following this procedure?

Yes, precisely.

 

[Weaselboy]

If you look at the Disk tab of Activity Monitor while that is going on, does it look like there is any file transfer happening?

 

[Brookzy]

If you look at the Disk tab of Activity Monitor while that is going on, does it look like there is any file transfer happening?

I've since cancelled the file transfer since it was nine hours into the second attempt with the same thing happening. However, the LaCie has a blue activity light on it, which was blinking throughout, and I could hear what sounded like read/write activity from both the source and target drives throughout the never-ending copy.

I've since reformatted (again) and I am now copying other files to different partitions on the LaCie - e.g. other files like TV shows and other media - and they seem to be copying without an issue. It's just the .backupdb folder from my iMac that is transferring forever.

Here's the partitioning situation on all my disks, in case I've partitioned/formatted in the wrong order or something. The 3TB is the old one, the 8TB is the new one:

/dev/disk0 (internal):
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:      GUID_partition_scheme                         500.3 GB   disk0
   1:                        EFI EFI                     314.6 MB   disk0s1
   2:                 Apple_APFS Container disk1         299.0 GB   disk0s2
   3:       Microsoft Basic Data BOOTCAMP                201.0 GB   disk0s3

/dev/disk1 (synthesized):
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:      APFS Container Scheme -                      +299.0 GB   disk1
                                 Physical Store disk0s2
   1:                APFS Volume Macintosh HD            174.0 GB   disk1s1
   2:                APFS Volume Preboot                 29.7 MB    disk1s2
   3:                APFS Volume Recovery                506.6 MB   disk1s3
   4:                APFS Volume VM                      2.1 GB     disk1s4

/dev/disk2 (external, physical):
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:      GUID_partition_scheme                        *3.0 TB     disk2
   1:                        EFI EFI                     209.7 MB   disk2s1
   2:                  Apple_HFS External                1.9 TB     disk2s2
   3:       Microsoft Basic Data Messenger               99.9 GB    disk2s3
   4:                  Apple_HFS Time Machine            999.9 GB   disk2s4
   5:                  Apple_HFS macOS Test Boot         49.4 GB    disk2s5
   6:                 Apple_Boot Recovery HD             650.0 MB   disk2s6

/dev/disk3 (external, physical):
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:      GUID_partition_scheme                        *8.0 TB     disk3
   1:                        EFI EFI                     209.7 MB   disk3s1
   2:                  Apple_HFS LaCie                   4.0 TB     disk3s2
   3:                  Apple_HFS Backups                 3.0 TB     disk3s3
   4:                  Apple_HFS Test Environment        500.2 GB   disk3s4
   5:       Microsoft Basic Data ExFAT                   500.0 GB   disk3s5

 

[Weaselboy]

They look like you have them GUID, which is correct. *scratches head*

 

[Brookzy]

I do seem to have a cursed history with Time Machine. I never seem to be able to go for more than a few months without having to start afresh. Until now this was a personal record, with the backup history going back to June!

As a possible pointer: Finder seems incapable of calculating the size of the .backupdb folder, sitting on "calculating size" for seemingly ever. Is this symptomatic of a corrupted Time Machine backup?

 

[BrianBaughn]

I don't even know how the Apple method is supposed to work. The backup folders contain "hard links" which to the Finder are actual files.

Would using Disk Utility's "restore" function work? I think I've done that before with TM disks.

 

[Weaselboy]

As a possible pointer: Finder seems incapable of calculating the size of the .backupdb folder, sitting on "calculating size" for seemingly ever. Is this symptomatic of a corrupted Time Machine backup?

I don't think so, with all those hard links it takes forever to calculate the size. I like @BrianBaughn's idea though.

 

[Brookzy]

I don't think so, with all those hard links it takes forever to calculate the size. I like @BrianBaughn's idea though.

Almost an hour later and it is still "calculating size"...

Hmm... can I image it straight onto the new disk without an intermediary? I don't have enough free space to take an image, and then restore an image on a new drive.

As an aside, why is it that local backups are in this horrendous ".backupdb" structure, whilst network backups from other Macs are neatly kept in a single .sparsebundle, which Finder knows the size of instantly, and which I can seem to copy without an issue? Is it something to do with local snapshots?

 

[Weaselboy]

Hmm... can I image it straight onto the new disk without an intermediary? I don't have enough free space to take an image, and then restore an image on a new drive.

Yep...

As an aside, why is it that local backups are in this horrendous ".backupdb" structure, whilst network backups from other Macs are neatly kept in a single .sparsebundle, which Finder knows the size of instantly, and which I can seem to copy without an issue? Is it something to do with local snapshots?

Time Machine needs an HFS+ formatted drive to function. So all the sparse bundle is is essentially a container that is formatted to HFS+ inside. So you can put the sparse bundle on a network or even another drive and use it as the HFS+ backup destination no matter the underlying format of the hard drive itself. If you open a TM sparse bundle you will see the same Backups.backupdb file inside.

Also a sparse bundle stores data in 8MB "bands" so it can trick the file system into storing files larger than the system supports. For example, if you had a FAT32 volume with its 4GB file size limit, you could put say a 6GB video inside a sparse bundle and move it to the FAT32 volume successfully. The the FAT32 drive, it just looks like a bunch of 8MB bands (files).

 

[Brookzy]

Yep...



Time Machine needs an HFS+ formatted drive to function. So all the sparse bundle is is essentially a container that is formatted to HFS+ inside. So you can put the sparse bundle on a network or even another drive and use it as the HFS+ backup destination no matter the underlying format of the hard drive itself. If you open a TM sparse bundle you will see the same Backups.backupdb file inside.

Also a sparse bundle stores data in 8MB "bands" so it can trick the file system into storing files larger than the system supports. For example, if you had a FAT32 volume with its 4GB file size limit, you could put say a 6GB video inside a sparse bundle and move it to the FAT32 volume successfully. The the FAT32 drive, it just looks like a bunch of 8MB bands (files).

I see, that is very clever. It would be nice if you could do that with local backups.

In conclusion for this thread, I gave up and started afresh with a new backup. Everything else transferred okay, including the .sparsebundles, so I guess there was some corruption in the .backupdb folder that copied forever.