Help with Backup - Seemed OK, but cannot read externally

[Tunes]

Maybe someone can explain what has happened with this backup:

VortexBox 1.10
Seagate 3TB USB 3.0 external drive for backup. (New, no prior use or formatting)
Plugged into VortexBox Appliance
Ran Backup from GUI
Completed in something over 24 hours

The following is at the end of the Backup Log:

total size is 1091374595243 speedup is 2.98
07/22/2012 20:38:29 - Backup finished.
07/22/2012 20:38:32 - You can now safely disconnect your USB drive.
07/22/2012 22:59:49 - USB disk /dev/sdb removed

When I connect the drive to a Windows PC to validate the backup, Windows reports that the drive requires formatting, which of course would overwrite the backup.
Notes:

The USB 3.0 drive was accepted with no complaint by the VBA.
The USB 3.0 drive did successfully load the device driver under Windows when connected to a USB 3.0 input port.
The USB 3.0 drive did successfully load the device driver under Windows when connected to a USB 2.0 input port, but said it would work faster with a 3.0 port.
The VBA has a 2 TB drive and slightly over 1 TB of music files.

I believe that the VBA backup program formatted the drive NTFS, and placed the labeling ID on the drive and that the drive SHOULD be able to be read by Windows.
By the "Backup finished." message, I believe the drive probably contains a valid image of the media. The backup process produced no error message.
To ensure the image is there and readable, I want to access it on another platform.
If I need to change procedure with the backup process, what should that be?
Any ideas?

[blownsi]

Maybe someone can explain what has happened with this backup:

VortexBox 1.10
Seagate 3TB USB 3.0 external drive for backup. (New, no prior use or formatting)
Plugged into VortexBox Appliance
Ran Backup from GUI
Completed in something over 24 hours

The following is at the end of the Backup Log:

total size is 1091374595243 speedup is 2.98
07/22/2012 20:38:29 - Backup finished.
07/22/2012 20:38:32 - You can now safely disconnect your USB drive.
07/22/2012 22:59:49 - USB disk /dev/sdb removed

When I connect the drive to a Windows PC to validate the backup, Windows reports that the drive requires formatting, which of course would overwrite the backup.
Notes:

The USB 3.0 drive was accepted with no complaint by the VBA.
The USB 3.0 drive did successfully load the device driver under Windows when connected to a USB 3.0 input port.
The USB 3.0 drive did successfully load the device driver under Windows when connected to a USB 2.0 input port, but said it would work faster with a 3.0 port.
The VBA has a 2 TB drive and slightly over 1 TB of music files.

I believe that the VBA backup program formatted the drive NTFS, and placed the labeling ID on the drive and that the drive SHOULD be able to be read by Windows.
By the "Backup finished." message, I believe the drive probably contains a valid image of the media. The backup process produced no error message.
To ensure the image is there and readable, I want to access it on another platform.
If I need to change procedure with the backup process, what should that be?
Any ideas?

I have had the same problem for well over a year. I've tried numerous usb drives, formatting with the vbox and formatting in windows and then moving it to the vbox, etc. Nothing solves this. I have every reason to believe that my backup is valid though because it will do incremental backups on the vbox machine. Anotherwords, if I add an album and backup. It finds the old backup and only copies the new album.

[blownsi]

Here's my post from 2010 on the very same subject:
http://vortexbox.org/threads/1706-US...rmatting-issue

[Tunes]

Here's my post from 2010 on the very same subject:
http://vortexbox.org/threads/1706-US...rmatting-issue

Thanks,

Yours does sound like the same issue.

One of the experts on this forum may have an idea what to do or what tests to try to resolve this.

[durks]

I wonder if sfdisk can do the wrong thing, in particular when large discs are used?

I don't have a system to test on, but a good place to start might be to confirm that the partition table on the USB discs mentioned here look okay. And, in particular, that, on those discs, the single backup partition has correctly been marked as id type 7 (=NTFS).

Using a command line on the VortexBox as root, can you run 'fdisk /dev/sdb' (or 'sd'<whatever> your drive is), type 'p', and copy the output here?

[Tunes]

I wonder if sfdisk can do the wrong thing, in particular when large discs are used?

I don't have a system to test on, but a good place to start might be to confirm that the partition table on the USB discs mentioned here look okay. And, in particular, that, on those discs, the single backup partition has correctly been marked as id type 7 (=NTFS).

Using a command line on the VortexBox as root, can you run 'fdisk /dev/sdb' (or 'sd'<whatever> your drive is), type 'p', and copy the output here?

Thanks so much durks.

Here is what is reported.

[vortexbox.localdomain ~]# fdisk /dev/sdb
Note: sector size is 4096 (not 512)

WARNING: The size of this disk is 3.0 TB (3000592977920 bytes).
DOS partition table format can not be used on drives for volumes
larger than (17592186040320 bytes) for 4096-byte sectors. Use parted(1) and GUID
partition table format (GPT).

Command (m for help):

It looks like the 3 TB size contributes to the problem. Would it be possible to have the backup process identify the size and use the recommended formatting?

I do not know what command line entries to make to do this manually, or even how to mount the drive so I can see if there is a backup present.

It seems like the most practical thing to do is to have a set of commands to do the same thing for larger disks as backup does for smaller drives.

[durks]

Hmm. What does 'parted' report for the same disc? (Run 'parted /dev/sdb' and, again, type p.)

[Ron Olsen]

3 TB drives are not supported on VB 1.10. They require the drive to be formatted with a GUID Partition Table (GPT) in order to use all 3 TB on the drive. This requires the use of the parted disk partitioning program. The VB 1.10 code formats the drive using sfdisk, which creates a Master Boot Record (MBR) partition table, which cannot support drives larger than 2 TB.

Also, support for USB 3.0 is problematical in Fedora. Other users have had problems trying to use USB 3.0 with VortexBox backup.

My suggestions:

1. Use a 2 TB USB 2.0 drive for backup on VB 1.10.

2. Upgrade your system to VB 2.0.

3. Reformat the 3 TB drive on VB 2.0; this will create a GPT partition table which uses all of the 3 TB on the drive.

4. Backup with the 3 TB drive, but use it in USB 2.0 mode, not USB 3.0.

Note that drives formatted with a GPT partition table cannot be read on 32-bit Windows XP systems, but can be read on 64-bit Windows XP, Windows Vista, and Windows 7.

[Tunes]

Hmm. What does 'parted' report for the same disc? (Run 'parted /dev/sdb' and, again, type p.)

Thanks again:

[vortexbox.localdomain ~]# parted /dev/sdb
GNU Parted 2.3
Using /dev/sdb
Welcome to GNU Parted! Type 'help' to view a list of commands.
(parted) p
Error: Can't have a partition outside the disk!
(parted) quit

Just in case it was fdisk with the p option:

[vortexbox.localdomain ~]# fdisk /dev/sdb
Note: sector size is 4096 (not 512)

WARNING: The size of this disk is 3.0 TB (3000592977920 bytes).
DOS partition table format can not be used on drives for volumes
larger than (17592186040320 bytes) for 4096-byte sectors. Use parted(1) and GUID
partition table format (GPT).


Command (m for help): p

Disk /dev/sdb: 3000.6 GB, 3000592977920 bytes
255 heads, 63 sectors/track, 45600 cylinders, total 732566645 sectors
Units = sectors of 1 * 4096 = 4096 bytes
Sector size (logical/physical): 4096 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Disk identifier: 0x38f06e59

Device Boot Start End Blocks Id System
/dev/sdb1 1 1565560768 1967275776 7 HPFS/NTFS
Partition 1 does not start on physical sector boundary.

Command (m for help):

[durks]

Looking at that fdisk partition table you can see that it doesn't make sense: e.g. the starting sector is a higher number than the total number of sectors. So sfdisk has tried to handle your disc, but has gone wrong. Whilst this is all evidentally struggling along (in some way!) in this version of Linux, you can understand why Windows won't mount the disc. And you don't want to use this disc like in this state for your backups.

You could probably work around this by manually reformatting the drive to contain a smaller (e.g. 2TB) partition, but I don't want to confuse matters, so I suggest you take Ron's advice.

(Note to Ron: You wrote: 'The VB 1.10 code formats the drive using sfdisk'. Actually, so does the VB 2.0 code - for some small values of 2.0! I know that, since that's the case on my own system which is using the original VB 2.0 release. We would benefit from a stricter release mechanism, I think.)