Backup Copy Job + WAN Accelerator

Super helpful thread.  Thanks Michael, and thanks OP for the super-fast and informational responses getting to the root of the issue.

If you do this, then definitely use High bandwidth mode based on the bandwidth metrics you provided, as a guidance:

<=100Mbps = Low Bandwidth mode

100Mbps< Bandwidth >=1Gbps = High Bandwidth Mode

>1Gbps = Direct

As long as your servers have sufficient resources to run the multiple roles, this should be fine to use gateway & wan accelerator on the same server.

Nice one! This would’ve also been impacting WAN Accelerator btw as WAN accelerator would've been talking to the gateway servers. Which, if you deployed a WAN accelerator at each site would’ve made the data flow:

Source Synology → VBR Gateway at source → WAN Accelerator at source → Wan accelerator at target → VBR Gateway at source (for target gateway though) → Synology at target.

So you’d have thrown traffic over the wan to the target wan accelerator, then back across the link to the vbr gateway in your source site, then back across the link again to talk to the synology at target!

We’ve certainly made things more efficient here!

Concur with Michael. These Gateway Servers he suggests adding will act as Proxies to perform the heavy load & lifting of the BCJ job processing.. I suspect once implemented processing rate will increase. The Helpcenter on BCJ discusses Gateways. 

Both sites have NAS Synology that has SMB share. 
Gateways are our Firewalls, we have firewalls on each location. Fortigate to be specific

Without any initial seed

I don't think processing rate will be lower, but I can't definitively confirm because I don't use WAN Accelerators. Depending on your total BCJ job size, your job shouldn't take 6-7 days to run. Just use Michael's formula above, but instead of the 7TB for the 1 VM in the job, use the total job size. This will give you the time it'll take to run the whole job...approximately. Again, since subsequent runs are incremental, it won't take anywhere near as long. 

I just have a question about the BCJ without WAN Accelerator.

Processing rate, speed will be lower, so it will take even more than 6-7 days or?

Thanks for explanation :)

If the backup is gone, don’t worry about setting up sharesync again, I’d always be more worried about data corruption on such a large backup file. Just do the full BCJ without sharesync or wan accelerator 🙂

If you’re worried about your other VMs not processing whilst this large one runs, I’d create a separate BCJ for the big VM so it doesn’t prevent another sync cycle for your smaller VMs during the initial full backup copy 🙂

Okay, my advice would be:

• Cancel the BCJ, change processing mode to direct.

Yes your others will be waiting whilst your full backup takes place, it would’ve been possible to use the synology sharesync backup as a ‘seed’, to avoid another full, if Veeam validated it wasn’t corrupted, if you still have this backup, you could attempt to use it as a seed for your BCJ.

Assuming everything is equal, as in no bottlenecks greater than that of your WAN connectivity, the maths should look like the below:

Lets call the upload 550Mbps, as you’re not likely to hit 100% utilisation all the time.

550Mbps = 68.75MBps

I’m not going to get into the exact of Gigabyte vs Gibibyte so lets just say it’s 7 Terabytes, or 7,000,000MB.

7,000,000 divided by 68.75MBps = 101,818 seconds, or put in minutes: 1696.96 minutes, or 28.28 hours approximately.

So if you don’t have a usable backup in the destination to use as a seed, you can just disable WAN accelerator, throw the data directly to your offsite repository, and within say, lets round this up to <=1.5 Days, you’ll have a full copy there, and can carry on as normal.

This doesn’t factor in exactly any production WAN use, permitted transfer periods etc, but at the high level I believe the point makes sense.

Either don’t use wan accelerator or use high bandwidth mode 🙂 high bandwidth mode will try to give you a higher bandwidth throughput relative to your consumed bandwidth and is effective somewhat with this up to 1Gbps.

Personally, unless you have bandwidth constraints, I’d tell it to use direct (no WAN accelerator) and either use QoS or network traffic rules to limit the backup speed during working hours

Hi, if it’s 1Gbps are you using WAN accelerator in high bandwidth mode? I would either directly copy or use WAN Accelerator in high bandwidth only in that situation.