What is RAID on Synology NAS?

Synology DS419slim
Synology DS419slim (Image credit: Rich Edmonds / Windows Central)

What is RAID on Synology NAS?

Best answer: Redundant array of independent/inexpensive disks (RAID) is a technology that allows for the storing of data across multiple hard drives. With NAS, the aim of RAID is to achieve data redundancy to reduce data loss and improve performance.

What is RAID?

RAID stands for redundant array of inexpensive/independent disks. It's a group of independent drives that operate as a fused single array. You can think of it as two or more drives joined together to create a single pool of storage. This method helps to improve performance as well as offer redundancy in case a drive fails.

Should a drive fail and it's not configured in a RAID, you'll run the risk of losing stored data. When using RAID, we safeguard ourselves against such issues by reserving a portion of the total storage capacity for localized backups. If a drive fails and needs to be replaced, the stored backup data could then be used to recreate the storage volume.

Why you should use it on NAS

There are actually a few levels of RAID, depending on how many drives you plan on using, what kind of data redundancy is required, and total volume capacity.

Swipe to scroll horizontally
RAIDDrives requiredTolerable drive failuresData redundancyCapacityNotes
Basic10HDD sizeNo protection
SHR10-2VariesNo protection with single drive SHR
RAID 020HDD sizeNo protection
RAID 121-3HDD # -1 x smallest HDD sizeRow 3 - Cell 5
RAID 531HDD # -2 x smallest HDD sizeRow 4 - Cell 5
RAID 642HDD # -2 x smallest HDD sizeRow 5 - Cell 5
RAID 1042+HDD # -1 x smallest HDD sizeHDDs must be even number, tolerable to half the number of HDDs

The best RAID for Synology NAS largely comes down to the number of drives, but Synology's Hybrid RAID (SHR) is usually the best choice. It doesn't matter which enclosure you choose, even the best NAS for home requires some form of data redundancy or means for backup.

Rich Edmonds
Senior Editor, PC Build

Rich Edmonds is Senior Editor of PC hardware at Windows Central, covering everything related to PC components and NAS. He's been involved in technology for more than a decade and knows a thing or two about the magic inside a PC chassis. You can follow him over on Twitter at @RichEdmonds.