If you are planning on purchasing a NAS backup (Synology, Qnap, Netgear, Drobo, Buffalo, etc.) device to serve as a target for Hyper-V NAS backup, below are product features to consider before purchasing and when setting things up with your server backup software.
Storage Size and Expandability
The obvious starting point is overall capacity, storage size, and expandability. Are drives hot-swappable and what is the maximum capacity? Do all drives need to be the same model? Does the system allow mixed sizes?
Consumer-Grade or Enterprise-Grade Storage
This point can’t be stressed enough: when buying a NAS device for Hyper-V backups, the device absolutely must be able to handle the enormous rate of a typical data transfer. For example, if the source Hyper-V host runs on a striped RAID, it could serve transfer speeds of over 400MB/sec. After compression and deduplication, this rate may be reduced down to 50-100MB/sec but may be far too much for a consumer-grade device to handle.
The reason for this is simply that consumer-grade devices do not have the processing power and RAM to handle sustained high-speed traffic for hours. When you target multiple Hyper-V host backups to a single NAS device, the issue becomes even more critical.
When using a NAS device for Hyper-V backups, it’s important to buy a business-grade device with plenty of processing power on-board. See this article that compares enterprise to consumer grade. Otherwise, your NAS backup software would need to be throttled to slow down transfers to the NAS significantly.
Full NTFS Support
If you use the NAS backup device exclusively for Hyper-V backups, NTFS is not necessarily a must; however, most business users would want to also use the NAS storage for data backups. Since business file servers can become quite large and deep, and since business networks have complex user access regulations to follow, it’s crucial that the device handles NTFS correctly and is fully compatible. This compatibility ensures no file access permissions or other security settings are lost. In addition, NTFS folders can approach over 32,000 characters in length, much more than many other file systems permit.
Ideally the Hyper-V host and the NAS backup device (Netgear, Qnap, Drobo, Synology, Buffalo, etc.) should be connected via a crossover cable, which dramatically improves throughput. Alternatively, a separate network bus should be available for backup traffic only. Hence, the NAS device should have several NICs so that it can be accessed from multiple isolated networks.
In case you have a cluster shared volume setup, it’s even more important to separate network traffic. You would want the backup traffic to take an isolated route to the NAS backup device, so that CSV management packets are not affected and other network service traffic from and to the VM is also separated.
Access via iSCSI
One great way to ensure NTFS support is to create a LUN inside the NAS device and attach it directly via iSCSI to a Windows Server or PC. This puts Windows in control of the disk / volume and hence provides 100% compatibility with NTFS, even though the disk is served on a different operating system. On some lower powered NAS backup devices, this strategy improves performance as it removes the file system processing load from the device and shifts it to the Windows Server instead.
When working with Hyper-V backup traffic, however, this setup would create an additional “network hop” and increase latency and bandwidth usage and thereby decrease overall performance, unless it is the Windows Server itself that creates the Hyper-V backup.
Hyper-V NAS Backup Solution
Perhaps you can find a retailer that lets you test drive a Synology or Drobo for day, as you can do with BackupChain. Try our Hyper-V NAS backup or Hyper-V cloud backup for 20 days for free and see how your storage device and host servers perform under high load.