How do NAS backups handle a changing filesystem

[mark49808]

In most cases we would leverage API connectivity to do this for us, or a custom script to create a storage snapshot and back up from that.

But for vendors without support for that, and/or we haven't yet had the time to script the snapshotting, how does a NAS backup job (of an NFS or SMB share or even future S3 when available) handle a folder and contents that's changing (adds, deletes, changes) while the backup is running?

Does the NAS backup do some initial scan/inventory of files and just back those up? or is it crawling as it backs up so the state will be highly unpredictable and possibly even interfere with a delete operation or something (as Veeam is actively reading a large file to back it up).

Just wondering what issues we can expect or if the NAS backup engine has accounted for such things in any way. Or if snapshots are basically an unspoken "requirement" for this. Thanks in advance!

[Mildur]

Hi Mark

We will provide information on the future S3 backup after the release. It's too early to talk about it.
For todays file share backups: If you want to have consistency in your restore point, a snapshot is required.

At the beginning of a backup session, the job creates a file tree with all files available on the share. This list is compared against what's already in the backup repository.
Changed and new files will be protected. If the file changes while the job is running, we will still be able to protect it. But it will be the state of the file as it is on the share. If the file was deleted before the job could process it, it won't be protected.

Best,
Fabian