Does Backup Transformation cause network traffic?

[geets]

Hi,

I am trying to find possibilities to better the performance of backups.
Following is the setup:
We have one ESX-Host.
A VBR installation on a VM.
A Synology NAS used as primary target for backups. It's connected via SMB.

The backup job is configured to use backup mode incremental, wich synthetic full backups on saturday.
Also previous backup chains shall be transformed into rollbacks.

The transformation process takes about 40 hours.
First question: is that duration to be expected? Data is about 5TB.
Second: while the transformation process is running. Both the Backupserver and the NAS see traffic of about 100Mbit/s.
Is the transformation process the source of that network traffic between backup server and repository? I thought the transformationprocess should take place on the repository.

Thanks for your help!
Alex

[Gostev]

1. Yes, it is expected for low end NAS with non block-clone aware file system.

2. Transformation traffic is between the target data mover (running on a gateway server specified in the backup repository settings) and the NAS box. In case of NAS, our data mover cannot run on the NAS itself, so it can only read and write data over the network from the gateway server. In your case, it looks like the backup server itself is auto-selected as the gateway server for NAS.

Both of your bullets are the reasons why we strongly recommend using general-purpose servers with ReFS or XFS volume for backup repositories, as opposed to NAS. The costs are largely identical, but the benefits of the general-purpose server as your backup repository are overwhelming.

But since you already have NAS, consider turning into direct attached storage for your backup server using iSCSI protocol, in which case you will be able to use ReFS and accelerate your transformation performance by a few orders of magnitude.

[geets]

Thank you for that very informative answer. I understand a lot more now!