Do I understand Item-level vs Snapshot correctly?

[Peejay62]

Hi, I thought I understood correctly, but reading the explanations in the documentation put me in kind of doubt..
I'm taking a backup of my onedrive:
Snapshot based : I think I understand it but: on day X just take an image of my complete onedrive and retain that backup for as long as I have defined the retention. So If I run this backup only once with a retention of 1 year the coming year I have a backupset available that reflects the status of my onedrive for day X.
Item level: let's assume 3 years retention. In the backup all my onedrive data is selected for which the creation/modification date is within the past 3 years (looking back from the rundate). So run it on jan 1st 2021, within the backup will all data be from jan 1st 2018/(2019)/to dec 31 2020. Run it again on feb 1st 2021, will then all data timestamped jan 1st to jan 31 2018 be removed? Am I correct on that? Is this in effect a kind of sliding window? Maybe to add something to it: I thought the desired item level retention is applied to the "backupset". Reading some documentation I could understand that the retention is applied to individual items. (hope this is not the case..)
And now the apply retention policy: If I set that on daily, what will the effect be of that?
Sorry I am I bit confused, hopefully you can eleborate on this.

regards, Peter

[HannesK]

Hello,
you understood it correctly. Until your question "Am I correct on that?" everything is fine.

Item level backup retention is per item. With a 3 years retention, an item that is older 3 years will never be backed up. https://helpcenter.veeam.com/docs/vbo36 ... tml?ver=50

Best regards,
Hannes

[Mike Resseler]

Peter,

You choose snapshot based (it is not am image since that doesn't exist in application-level backups) when you want to restore a OneDrive (in your example) in the exact same situation as it is at the point in time of backup. No matter how new/ old the files are. When the retention kicks in (say you have a 30 days retention) then the way your OneDrive looked 31 days ago will be removed, but obviously you still have the backup from yesterday, day before... until -30 days

You choose item-level if you have an SLA or legal requirement to keep everything for X amount of time. A lot of organizations need this for compliancy / legal and so on. At this point in time, we look at the create/ changed date of the item (file/ mail/ ...) and only back it up when it is within the retention age. When cleaning up, we remove all items older than the retention age. In this case, it could be that your OneDrive holds 100 files, but you only protect 70 of them because the others are older then the retention age.

I hope it makes sense

[Peejay62]

Ok, thanks for clarifying. Concerning the term "Image" I used in this context, I kinda used it wrong.The term Image was used to describe that a complete picture of all available files is taken into acccount.My bad.
Last thing, just to make sure: when I take an item level backup today with a retention of 1 year and run this backup only once. The backup will only select items (created/modified) from the past 365 days. Regardless of running expiration policy on a daily basis, the backup entries will become obsolete and removed on day 366 from now?

thanks,

[Mike Resseler]

Correct. However, backup entries that (for example) are now 360 days old already (created or modified date) will be removed in 5 days. Because then they will become older then 1 year

[staun]

I know this thread is old. But I just realized that Item-Level backup on Office365 does not include files that are old than the retention. So we just lost a lot of files in one persons OneDrive and just double check other peoples onedrive. Again files that have not been modified for 180 days were gone in our Item-Level backup.

I thought I had done something wrong and contacted our backup supplier support and they said this was by design, which surprised me a lot, as we make a lot of software that our engineers work on for a couple of weeks and then it just rest for a long time, just to be picked up again if needed. This is were I don't understand it, I thought every backup would keep all files within the retention time and not exclude files without modification.

So now I am converting everything to Snaphsot based backup.

[Mildur]

Hi Jørgen

Depending which VB365 version you initially deployed, you could still using the original item-level retention policy. We released snapshot-based with Version 3.0 in April 2019.