NETGEAR is aware of a growing number of phone and online scams. To learn how to stay safe click here.
Forum Discussion
Freddeco
Mar 13, 2017Aspirant
Backup fails after upgrade to 6.6.1
Hi, I have been running a 2 disk 2TB mirror in xraid readynas with full backup to external hdd once a week without any issues. I have about 228GB of data and 30GB of snapshot. not a lot. Aft...
- Mar 16, 2017The point is not "how many snapshots" but "is it transferring snapshots". Did you try StephenB suggestions?
Snapshots are at block level, understand that they contain only the blocks that are different from a reference, which makes them very efficient is used space.
Traditional backups, such as what you're using, occurs at file level. It doesn't have a clue that it's a snapshot, it only considers the files it sees - the full files - the files reconstructed with the blocks in the snapshot merged with the reference(s) - the files like you would see if you were to browse the share.
If the backup tries to transfer a single snapshot, it would require the whole file size, two snapshots, twice. If you have a share with two empty snapshots and transfer the data and the snapshots, it requires THREE times the space.
In FAT, there are other limitations, like the maximum size of a file, which is much lower than the maximum file size on BTRFS. If you were to try transfer a file too big for FAT, it would fail.
jak0lantash
Mar 16, 2017Mentor
The point is not "how many snapshots" but "is it transferring snapshots". Did you try StephenB suggestions?
Snapshots are at block level, understand that they contain only the blocks that are different from a reference, which makes them very efficient is used space.
Traditional backups, such as what you're using, occurs at file level. It doesn't have a clue that it's a snapshot, it only considers the files it sees - the full files - the files reconstructed with the blocks in the snapshot merged with the reference(s) - the files like you would see if you were to browse the share.
If the backup tries to transfer a single snapshot, it would require the whole file size, two snapshots, twice. If you have a share with two empty snapshots and transfer the data and the snapshots, it requires THREE times the space.
In FAT, there are other limitations, like the maximum size of a file, which is much lower than the maximum file size on BTRFS. If you were to try transfer a file too big for FAT, it would fail.
Snapshots are at block level, understand that they contain only the blocks that are different from a reference, which makes them very efficient is used space.
Traditional backups, such as what you're using, occurs at file level. It doesn't have a clue that it's a snapshot, it only considers the files it sees - the full files - the files reconstructed with the blocks in the snapshot merged with the reference(s) - the files like you would see if you were to browse the share.
If the backup tries to transfer a single snapshot, it would require the whole file size, two snapshots, twice. If you have a share with two empty snapshots and transfer the data and the snapshots, it requires THREE times the space.
In FAT, there are other limitations, like the maximum size of a file, which is much lower than the maximum file size on BTRFS. If you were to try transfer a file too big for FAT, it would fail.
- FreddecoMar 17, 2017Aspirant
jak0lantash wrote:
The point is not "how many snapshots" but "is it transferring snapshots". Did you try StephenB suggestions?
Snapshots are at block level, understand that they contain only the blocks that are different from a reference, which makes them very efficient is used space.
Traditional backups, such as what you're using, occurs at file level. It doesn't have a clue that it's a snapshot, it only considers the files it sees - the full files - the files reconstructed with the blocks in the snapshot merged with the reference(s) - the files like you would see if you were to browse the share.
If the backup tries to transfer a single snapshot, it would require the whole file size, two snapshots, twice. If you have a share with two empty snapshots and transfer the data and the snapshots, it requires THREE times the space.
In FAT, there are other limitations, like the maximum size of a file, which is much lower than the maximum file size on BTRFS. If you were to try transfer a file too big for FAT, it would fail.it was indeed the snapshot ot a home user folder that was the culprit.
thanks for the help.
regards,
Frederic
Related Content
NETGEAR Academy

Boost your skills with the Netgear Academy - Get trained, certified and stay ahead with the latest Netgear technology!
Join Us!