We are in the process of implementing a backup strategy for our 72TB QNAP NAS (with RAID-5), which currently holds around ~40TB of data (total useable space ~60TB).
Our setup includes one primary NAS and two backup NAS units. One backup NAS is located onsite and the other is at a remote location.
Our initial backup strategy is as follows:
Configure snapshots on the main NAS, stored both locally on the main NAS.
Backup selected important folders from the main NAS to the local and remote backup NAS via Hybrid Backup Sync.
I have a few questions and would appreciate your input:
Does this approach seem sound and reliable?
Our main NAS has a single encrypted volume composed of 12TB 6x drives. In the event of hardware failure or data corruption/loss, will this backup strategy provide effective recovery?
Should we consider a full backup on onsite backup NAS? Don’t we need to have at least twice the size of the main NAS content? So that one full backed up copy is available even if the backup is currently ongoing. Or does QNAP’s Hybrid Backup Sync (HBS3) handle this more efficiently with a one-to-one ratio?
How much storage space should we allocate for snapshots, considering this is our first time configuring them for 40TB of existing data? According to the documentation, snapshots are space efficient and it’s generally recommended to reserve around 20% of the original data size. However, I’ve come across user experiences online reporting that snapshots consumed as much as 55–60% of the original data size.
1.) I like to apply a multi-layer backup strategy both local and cloud. If I had a business with multiple sites, then I would do an off-premise backup as well.
2.) In my local backup, I backup up my main bits of data to my second NAS. I also backup my TimeMachine backups to an attached USB drive. In addition I do snapshots of my volumes and I have snapshot replicas of my volumes on the second NAS.
3.) On my second NAS, it is mainly backups right now but I also have a TimeMachine backup on that unit. So I then take snapshots of that volume and send it back to the first NAS in a Replica process.
4.) Snapshots are great. They are exceptionally space efficient. I am not quite sure how they can effectively backup my data and take up less space than my data. How much space you allocate for them depends on how many snapshots you want to keep. If it’s just a few then maybe 5% to 10% is fine for guaranteed snapshot space (I’ve not seen anything close to them taking 55 to 60% of space unless people are keeping hundreds of snapshots). And you don’t have to guarantee snapshot space either if you don’t want to. Your system will save snapshots in available space on the drive, but if you start but if that space is needed for file storage than your snapshots will start to be deleted. If you do snapshot replicas to your second NAS, the second NAS has to be the same size in drive space or larger. This is because if your first NAS fails, you can completely restore it to the second NAS. I’m not sure if you are using QuTS Hero but the way Hero does allocation of drive space makes the snapshot vaults really effective as you can way over-subscribe your drive space.
5.) HBS is great. I’m torn if I need to do an HBS backup when I do snapshots. But it does very good at keeping data backed-up. It is not like snapshots so it will be the size of your volume (minus any deduplication if you select that) plus the size of the incremental versions.
If I were you here’s what I would do. Your mileage may vary, but this is me:
1.) Keep a full backup on your second NAS on site using HBS.
2.) Keep snapshots of your volumes and vault them to your second on-site NAS.
3.) Repeat steps one and two for the remote NAS.
4.) Have a cloud based service like QNAPCloud and backup your most critical items there. It’s more expensive than your own storage so get a much smaller drive space and backup just the super critical stuff.
Others may have a more enlightened or better approach than myself.
To ensure foolproof data protection, QNAP recommends performing local snapshots and full backups on both the local (on-site) and off-site backup destinations. However, off-site backup must also consider potential limitations due to bandwidth or cost. A tiered backup strategy can be adopted, prioritizing critical data for off-site backup to balance protection strength with practical constraints.
QNAP’s HBS employs incremental backup and supports multi-version control, effectively saving space. As long as too many version histories are not enabled during backup, generally, reserving space approximately 1.2 to 1.5 times the usage of “critical data folders” is sufficient for daily backups and changes.
Additionally, if bandwidth and space are sufficient, consider implementing the Snapshot Replica mechanism. Through Snapshot Replica, snapshot data from the primary NAS can be backed up to both the local backup NAS and the off-site backup NAS. In the event of data anomalies on the primary system, this allows for direct and rapid mounting of the entire volume from a specific point-in-time snapshot for immediate restoration, without the need to organize backup data.
For snapshot guaranteed space, a preliminary estimate of 20% of the entire Pool on the local machine is usually sufficient. This setting assumes your data change rate is between 5% and 10%. Of course, if your data storage type or storage application has very large daily changes, you’ll need to adjust and increase this ratio. For the off-site NAS, if you’re using Snapshot Replica, you’ll need to prepare space equivalent to your current data size plus an additional 20-50%.
Therefore, a more neutral recommendation is: if data change is high, I’d more highly recommend using HBS and focusing on backing up critical data; for environments with low data change, both HBS and Snapshot Replica are excellent choices, differing only in whether your restoration objective focuses on data or the entire volume.
Furthermore, HBS also supports backing up data to various cloud services. Whether it’s your personal cloud space like Google Drive / Box / OneDrive, or your company’s enterprise-level AWS / Google GCP / Azure, you can create another off-site and secure backup there. In addition, QNAP has also launched myQNAPcloud One cloud space, allowing customers to achieve the most cost-effective off-site backup. Its subscription fee is only charged based on storage volume, making it the lowest-cost option compared to major well-known public clouds.