File Level backup - Sizing

[ammarrasheed]

Dear all,
We need to onboard a customer for BaaS for backing-up its local files. Since its a Physical Server and its on customer's premises, Veeam Agent for Windows is required.

- File-Level Backup" will be performed by Veeam Agent for Windows.
- The destination end point of Veeam Agent is Veeam Cloud Connect (hosted on our data center).
- Following is the customer requirement:
Customer file(s) to be backed-up: 150 gb
Daily rate of change of this file(s) is expected to be 4 GB per day. Pls guide is this rate of change is required for "File level backup" as well, just like we do with VM level backups via VBR ? or this information is not required for file-level backups?
Retention Policy: 30 days, Daily Incremental backups and Weekly full backup. (please let me know if any of this information does not pertain to file level backup as we are used to do this on VM level backups).

I will be greatful, if you can also provide a generic formula for calculation for this, so if requirement do change in future, we can do that easily.
thanks alott !!

[HannesK]

Hello,
the change rate for file backup is often higher than for image level / block level backup. Keep in mind that if 1byte in an 1 GByte file changes, then the full 1 GByte needs to be backed up.

There is no serious way to predict the impact of file based vs. block based backup.

Not sure what you mean with formula of adding number of changes, but if Excel does not do the job for you, I can recommend rps.dewin.me

Best regards,
Hannes

[ammarrasheed]

Hi Hannes,
Thanks for your reply.
As far as i know. Restore Point simulator is not supposed to mean for file level backups via Veeam Agent.
If it is, I would be greatly thankful to show me how it can be done via this simulator.

Formula means...I need to calculate the backup storage quota required for 30 days retention. How should I calculate it ? without having this info I can not offer a PO to customer to onboard with us. All costing/Pricing from business team relies on this information that how much size of storage will be utilized. Also we as tech team also must be awared that how much amount of storage will be deducted so we can predict future stuff accordingly.

Moreover, I couldnot understand your statement: "if 1byte in an 1 GByte file changes, then the full 1 GByte needs to be backed up". Can you pls elaborate ?
Thanks

[HannesK]

Hello,

storage quota required for 30 days retention. How should I calculate it ?

(1 full) + (30x incremental size) assuming that you use REFS with block cloning for your fulls.

Can you pls elaborate ?

if you store data to a disk, then the data is stored in blocks. Let's say the file system block size is 4 KBytes. And 1 byte has changed in a 1 GByte file.

Block based backup (the default and what Veeam Agent for Windows is built for) would backup 4 KBytes (one block).
File based backup would backup the whole file. Because it's "file based"


I don't know, why you want to back up file based. But without knowing the real file based change rate, it is not possible to give any estimation.

Best regards,
Hannes