NAS Synology (ISCSI or SMB network share)

[BostjanUNIJA]

Hi.
What is more proper way of adding backup repository if you have NAS SYNOLOGY as destination.

A) creating a shared folder on NAS Synology and adding it as a back repository over network share on Veeam B&R
B) creating ISCSI disk, adding it to Veeam B&R and format it with REFS file system?

thank you for your replies.

[tyler.jurgens]

Both are supported methods. I would choose option B though.

[rennerstefan]

I would choose B as well due to ReFS benefits and FS handling by the repo server.

[karsten123]

How do you think, Synology is officially supported with iSCSI and ReFS? Can you post the official msft dokument?

[rennerstefan]

Microsoft does not list sepcific vendors for ReFS support when using them as backup targets but rather says:
“ Backup targets include the above supported configurations. Please contact application and storage array vendors for support details on Fiber Channel and iSCSI SANs.” (https://learn.microsoft.com/en-us/windo ... s-overview).

And synology is listed (depending on model) as requested here:
“All ReFS supported configurations must use Windows Server Catalog certified hardware”

So for sure you need to check with synology on the support question but from a technical side I’d go with the ReFS over the SMB.

[jacobpalm]

Another vote for iSCSI and ReFS. I've used it with tons of Synology devices for customers, without any issues. I wouldn't want to be without the space savings and fast clone features Veeam delivers on ReFS.

[BostjanUNIJA]

I have read somewhere (or 'missread') that having Refs file system for backup repository would make backups even smaller.
So I compared backup to NAS over SMB and backup to NAS ISCSI/REFS and haven't noticed any size difference. Maybe just wrong information found on the internet they it would make a difference of the size.

[ITP-Stan]

The technique is called block cloning.

When using ReFS you have the benefit of virtual full back-ups that take up almost no space.
While using NTFS or using a SMB share, your virtual full back-ups will always take up full space.
So ReFS is ideal for back-up copies with virtual fulls (maybe GFS), so you can store multiple virtual full back-ups without needing a whole bunch of space.

For normal Forever Forward Incremental back-up chain with 1 full and x amount on incrementals, there is no space savings. But there is a significant amount of time saving because injecting an incremental in to the full is very fast (only metadata changes) instead of reading and writing all the blocks!

I use it a lot for back-up copies. However officially I don't think Microsoft supports using ReFS on iSCSI with Synology NAS.
So if the volume becomes corrupt because of power or connectivity loss there is no help, just accept the loss and start over.
You should have offline copies as well anyways.

PS: XFS on Linux also has block cloning functionality. So you could also create an iSCSI volume and mount it on a Linux server and use that as a repository in Veeam.

[Martin Damgaard]

We chose option C instead...
I simply added them as Linux repositories.

The two Synology's for offsite backup and archival are at remote locations.
So adding them as Linux repositories has the added benefit of moving a lot of the work to the remote NAS.
Instead of doing healtchecks and merges over the slower connection to the remote locations.
(This also secures datat integrity, if the WAN connection goes down in the middle of processing merges or other tasks)

We have been running it this way for the last 5-6 years, and very happy with it.

[karsten123]

Hi Martin,
can you please explain how you „simply added them as Linux repositories“?
Tia.Karsten

[GregorS]

For the record (maybe option D, a variant of option C): you can create and run virtual machines on Synology. Have a Linux VM consuming local storage on Synology, format it with XFS and enjoy block cloning and immutability.

[ITP-Stan]

Option C as it's called by Martin is a rabbit hole with a lot of caveats.
It only works on x86 CPU, so no low-grade NAS. You need to open SSH, and I think some dependencies needed to be fixed.
And I thought that from DSM 7.x on it no longer worked at all, but I could be mistaken.

Option D as GregorS says is the better way, running a Linux VM on your Synology NAS (still needs to be x86) and use XFS file system.

[juansv]

I Liked the Option C

[Andreas Neufert]

Option C (running the Linux Repository directly on a NAS with x86 CPUs) is in general an ideal way. That said you need to tune the system for it a bit. sshd conf need to be tuned that ssh server does not drop connections and enhance maximum number of connections massively. As well you need enough RAM to handle Veeam there. It might work nicely for a small environment, but would become tricky with a medium sized envionments.

I would always choose an iSCSI volume with ReFS or XFS with enabled block cloning (RefS and XFS requirements need to be met so that it can work).

[BostjanUNIJA]

Thank you all for your replies.