Synology's recent focus on its higher-end business NAS appliances has meant some of its SMB boxes have had to wait in line for a refresh. Its highly popular DS1815+ is overdue for an update as it's now well over two years old and the latest DS1817+ aims to remedy this. Along with options for 10-Gigabit (10GbE) upgrades, the 8-bay DS1817+ is one of Synology's first appliances to support M.2 SSDs. A big disappointment is the lack of CPU upgrade as it still uses the same aging Atom C2538 SoC as its predecessor. This CPU is over four years old and along with support for slower DDR3 memory, the entire Atom C2000 family is currently suffering the ignominy of being accused of bricking devices that use them. This is due to a clock signal component that degrades after prolonged heavy usage and stops the device from booting. Synology has stated that it is aware of this, hasn't seen any abnormal error rates in its appliances that use these CPUs and has extended the warranty on older appliances (including the DS1815+) by an extra year. This shouldn't be an issue with the DS1817+ as two different sources from Synology confirmed to IT Pro that it has applied the suggested improvements to address this issue'. Synology's hybrid RAID feature now supports single-drive and dual-drive redundancy

Design changes The DS1817+ uses the same sleek black chassis as the DS1815+ but with a number of modifications at the rear. The quad Gigabit, triple USB 3 and dual eSATA ports have been relocated to the base of the panel leaving room at the side for a single PCI-Express expansion slot. This supports industry-standard 10GbE adapters from Intel and Emulex. The DS1817+ doesn't have embedded M.2 SSD slots so you'll need to forego 10GbE upgrades and install Synology's M2D17 expansion card which costs around 140 and supports two 2280/2260/2242 M.2 modules. The two SO-DIMM memory slots have been moved under the motherboard and are easily accessible behind a removable panel. The DS1817+ is offered with 2GB or 8GB of memory but if you want to upgrade to the maximum 16GB you'll need to write these off. Another change that won't go down well with existing users is the DS1817+ only supports the new DX517 expansion units and is not listed as compatible with the older DX513 models. These new 5-bay units allow the drive count to be pushed to 18 and capacity using 10TB drives to a very usable 180TB. We had no problems adding a dual-port 10GbE adapter to the DS1817+ 10GbE performance For testing, we fitted four 10TB Seagate IronWolf NAS drives and used Synology's discovery web portal to load the latest DSM software and create a big 27.3TB SHR array. Synology's hybrid arrays simplify RAID choices as they can be easily expanded with new drives and DSM 6.1 offers an SHR-2 dual redundancy option as well. NAS performance is impressive as with the appliance hooked up over 10GbE to a Lenovo x3550 M5 Windows rack server, we watched Iometer record raw read and write rates of 9.2Gbits/sec and 4Gbits/sec for a mapped share. Real world speeds are also good with a 25GB drag and drop file copy returning read and write averages of 4.4Gbits/sec and 3.2Gbits/sec.