Synology RackStation RS820RP+ review: Powerful, but pricey

A slimline rack NAS with a fair turn of speed and superb data-protection features – it’s not cheap, though

£956 exc VAT (diskless)
  • Great IP SAN performance
  • Tons of backup options
  • Expandable
  • Real-world performance is somewhat disappointing

Synology’s four-bay RackStation RS820+ NAS is a significant upgrade on its predecessor, the RS818+. That model, introduced two years ago, was held back by an ageing Atom C2538 CPU and relatively slow DDR3L memory; the RS820+ sports a more powerful quad-core 2.1GHz Atom C3538 and faster DDR4 RAM. The RS820RP+ model we tested also adds power redundancy courtesy of dual 150W hotplug power supplies.

Interestingly, the new appliance has also gained 2GB of base memory embedded onto the motherboard. That means its single SODIMM slot can be used to boost capacity to a total of 18GB, a modest step up from the 16GB on the older model. Upgrades are easy: you simply need to undo the four screws holding the lid down to gain immediate access to the memory slots.

The appliance has a spare PCIe slot too, which will accept a good range of 10GbE network adapters – or you can fit Synology’s M2D18 dual-slot M.2 SATA/NVMe SSD card to provide a high-performance cache.

One thing that hasn’t changed is the standard port count. You still get four embedded Gigabit Ethernet and dual USB 3 sockets, along with a single rear eSATA port, which can be used to double the drive count by connecting Synology’s four-bay RX418 disk shelf.

Deploying the RS820RP+ proved simple, as Synology’s discovery web portal quickly found the appliance on the lab network, initialised it and loaded the latest DSM 6.2 software. We then installed three 14TB Seagate IronWolf NAS drives and used the DSM Storage Manager app to create a 24TB storage pool. We used Synology’s versatile SHR format for this, but you can also create standard RAID5 or 6 arrays if you wish.

For performance testing, we installed an Emulex 10GBase-T card in the appliance and mapped a share to a Dell T640 Xeon Scalable tower server running Windows Server 2019. In this configuration, Iometer recorded raw read and write NAS speeds of 9.2Gbits/sec and 4.1Gbits/sec – a notable step up from the old RS818+, which managed 7.9Gbits/sec and 3.2Gbits/sec in the same tests. 

The gap was smaller in real-world scenarios, however. Drag-and-drop copies of a 25GB file on the RS820RP+ saw average read and write speeds of 4.8Gbits/sec and 3.3Gbits/sec, which was barely ahead of the RS818+’s 4.6Gbits/sec and 3.1Gbits/sec. And our backup test, using a 22.4GB folder containing 10,500 small files, completed at exactly the same 1.9Gbits/sec on both devices. 

The RS820RP+ did pull ahead with encrypted shares. Here our 25GB test file was written at 1.5Gbits/sec – 0.4Gbits/sec faster than the RS818+. And its strongest suit is IP SAN performance: using a 500GB target, we attained read and write speeds of 9.1Gbits/sec and 5.2Gbits/sec, a clear cut above the RS818+’s 6.1Gbits/sec and 3.5Gbits/sec. 

As for software features – well, Synology’s DSM platform won our sister title PC Pro’s Business Software of the Year award in 2019, so it’s safe to say you won’t be disappointed by its capabilities. A wealth of data-protection tools makes the RS820RP+ ideal as a backup vault, with Synology’s classy Active Backup for Business (ABB) app offering full backup, restore and disaster-recovery services for Windows servers and workstations, plus VMware vCenter and ESXi hypervisors. It’s recently been updated for Hyper-V too, and can protect VMs created on Windows Server 2016 and upwards. 

We also like the Snapshot Replication app, which supports on-demand and scheduled snapshots of Btrfs volumes with NAS folders and iSCSI LUNs, and can replicate them to remote Synology appliances. Meanwhile, the Hyper Backup app manages local, remote and Rysnc backups, with the Cloud Sync app adding support for plenty of cloud-storage providers.

On the other hand, although the RS820RP+ is an impressive NAS appliance, it’s quite expensive for the hardware spec: Synology’s desktop-format DS1819+ remains our top pick for SMBs, as it offers twice the memory, eight drive bays and 10GbE options for a similar price. But if you’re after a rackmount solution with power redundancy, the RS820RP+ fits the bill admirably and delivers unbeatable data-protection services. 

Synology RackStation RS820RP+ specifications


1U rack


2.1GHz Intel Atom C3538


2GB DDR4 (max 18GB)

Storage bays

4 x hot-swap SATA drive bays

Storage included



2 x 150W hotplug PSUs

RAID support

RAID0, 1, 10, 5, 6, hot-spare, JBOD, SHR


4 x Gigabit Ethernet

Other ports

2 x USB 3, 1 x eSATA, 1 x PCIe Gen 3 expansion slot


Web browser management


3yr hardware warranty

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