Using Azure storage account as a repository

[SimonSB178]

Hello,
Using Azure pricing calculator, I am trying to figure out an approximate estimate of performing backup on a storage account. However, I can't find any detail regarding the number of write, read, iterative read, iterative write operations, and data retrieval. Azure charges more the more operations you perform on a blob storage account.
Let's say, for example, that I have a full backup running weekly and transferring 916 GB of data. How many "operations" are we talking about in terms of read, write, iterative read and iterative write on an Azure storage account?
Thank you very much for your help.

[Mildur]

Hi Simon

Object storage is forever incremental. The backup server will write one full backup and then only new or changed data to the repository.

To calculate an estimation, you need to know how large a full backup is and how large your incremental. Each backup (initial full backup or incremental backup) will be written to smaller 1MB blocks. Take the size of your expected backup file and divide it through 1MB. That will give you an estimation of the required Write Calls.

Code: Select all

Backup size in MB / Block Size

Read calls are more difficult to calculate. They are mainly used when running a restore. And here it depends on how much data you will restore. We don't have to read everything when doing a restore. We only read objects belonging to the restored data. With immutable Azure Blob storage, there will also be calls to extend the immutability of objects every approx. 10 days.

If you want to not worry about calculating calls, you may also check out providers of object storage which do not bill you for the API calls or egress traffic. Such as Wasabi.

Best,
Fabian

[SimonSB178]

Hello Fabian,

Thank you very much for your reply.
If I understood correctly, in the case of a backup size of 916 GB, would it mean 916000 blocks?

Also, are the full backup size and incremental backup size the ones I see when I go into the tape backup job properties and click on "Backups?" These ones, to be clear:



Because right now, if I go and check this job manually, it always displays the same number: 916 GB processed, 916 GB read, and 916 GB transferred. Regardless, these numbers differ very much from the ones I see in the job properties above.
For the record, even though it specifies an incremental backup size, the "archive incremental backups to tape" option is not checked.

[Mildur]

You can check filesize of the VIB/VBK files on your primary repository.

Best,
Fabian

[SimonSB178]

Hi Fabian,

There are only .vbk files, meaning that there is no scheduled incremental. As the retention is 5 weeks, and the backup runs once per week, I'm assuming the total amount of data stored on the storage account will be the sum of 4 full backups, am I right?

[veremin]

Can you kindly share the retention settings of a job in question (number of restore points, schedule, full backup configuration, etc.), so we can be more precise with out estimations? Thanks!

[SimonSB178]

Hello veremin,
Sure thing! As I mentioned before, the job is a tape backup job.

Media Pool
Tapes: 48
Free space: 17.8 TB
Media set: Do not create, always continue using current media set
Retention: Protect data for 5 weeks
Parallel processing: Disabled
Encryption: Disabled
Export to vault: do not export
WORM: False
Incremental Backup
Nothing checked
Options
Nothing checked
Schedule
Run the job daily every sunday at 9:00 AM

Please let me know whether you need more information.

[veremin]

This seems to be a tape job configuration, while we were more interested in seeing the settings of backup or backup copy job pointed to Azure Blob object storage repository. Thanks!

[SimonSB178]

Hello veremin,

Sorry for the misunderstanding. The actual backup job is configured as following:
Backup to QNAP, with a retention policy of 15 restore points (so I'm guessing 1 full backup and 14 incrementals? I'm not sure how to figure this out).
Only the "Secondary backup destinations" option is checked (this being the tape backup job).
The backup is scheduled to run daily from Monday to Saturday at 9:00 PM.
Is this enough? Or do you need more information?
Also let me specify that the purpose of my question is considering a viable option to the tape backup, so basically Azure storage account would become the secondary backup destination in place of a backup tape job (if it makes sense). That's why I'm trying to make an estimate of the total cost, to see which is cheaper.
Thank you very much.