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Synology 5bay Expansion Unit DX517 (Diskless) 157 mm x 248 mm x 233 mm

  • Based on 413 reviews
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Availability: Only 8 left in stock, order soon!
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Arrives Thursday, Dec 26
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Features

  • Easily add 5 additional drive bays to Synology NAS. Please check Synology website for compatible models
  • Supporting both 2.5" and 3.5" SATA drives
  • Hot-swappable drive tray design
  • Synology DX517 can be used as a dedicated local backup solution for the Synology DiskStation. When created as a separate volume, the DX517 provides a great backup solution to its local hard disks in case of system failure

Description

5-bay 3.5/2.5 SATA expansion Easily add 5 additional drive bays to Synology DiskStation. Supporting both 2.5 and 3.5 SATA drives, DX517 is a flexible solution supporting on-the-fly volume expansion or serving as a local backup destination. Online volume expansion Managed from DiskStation Manager on the host NAS, the additional bays in the DX517 are immediately ready to be used once connected. On-the-fly volume expansion ensures that storage and services on the host are not interrupted during volume expansion. Hot-swappable drive tray design The hot-swappable drive trays of DX517 allow easy drive installation and replacement without powering down the system. Screwless drive tray design reduces the time needed for system setup. Dedicated local backup solution Synology DX517 can be used as a dedicated local backup solution for the Synology DiskStation. When created as a separate volume, the DX517 provides a great backup solution to its local hard disks in case of system failure. Host Interface: eSATA Package Contents: DX517 Drive Enclosure 1 x Accessory Pack 1 x AC Power Cord 1 x Expansion Cable: eSATA 1 x Quick Installation Guide Host Interface: eSATA Product Type: Drive Enclosure Product Type: Drive Enclosure Compatibility: Synology DiskStation Servers: DS1817+ DS1517+ Manufacturer Part Number: DX517 Packaged Quantity: 1 Limited Warranty: 3 Year Weight (Approximate): 8.62 lb Form Factor: External Form Factor: External Manufacturer: Synology, Inc Product Model: DX517 Product Name: DX517 Drive Enclosure Brand Name: Synology Brand Name: Synology Country of Origin: Taiwan Height: 6.2 Width: 9.8 Depth: 9.2 Number of Total Expansion Bays: 5 Number of 2.5/3.5 Bays: 5 Environmentally Friendly: Yes Environmental Certification: RoHS Number of Total Expansion Bays: 5 Number of Hard Drives Supported: 5 Number of 2.5/3.5 Bays: 5 Cooling Fan: Yes

Brand: Synology


Item Dimensions LxWxH: 9.76 x 9.17 x 6.18 inches


Size: 157 mm x 248 mm x 233 mm


Compatible Devices: Desktop


Item Weight: 8.62 Pounds


Product Dimensions: 9.76 x 9.17 x 6.18 inches


Item Weight: 8.62 pounds


Manufacturer: Synology America Corp


Language: English


Country of Origin: Taiwan


Item model number: DX517


Batteries: 1 Lithium Ion batteries required.


Is Discontinued By Manufacturer: No


Date First Available: April 13, 2017


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Thursday, Dec 26

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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Top Amazon Reviews


  • Top Value Prosumer/Small Business Storage Solution.
Style: Unit
I've been using data storage products for decades professionally and at home. I used to build my own and eventually almost 10 years ago ended up with Synology. So far Synology has exceeded my (very high) expectations. A product should be judged on several metrics: 1) product - the thing you buy 2) Life cycle - the thing you buy over the period you have it 3) support - can you get support when (not if) you have problems First, Product. Synology DX1517: I added this DX1517 to my DS1517+ at my home office. I'll touch on overall Synology but focus on the DX1517 (this product). Synology storage products are centered around a Linux-based DSM, or Disk Station Manager that runs on their DS (Disk Station) line. For a home/small office environment, it's extremely powerful. DSM has very strong base functionality that is complimented by a long list of applications that you can add from both Synology and 3rd party vendors. Like Apps for your PC or phone, many of those applications are free. But like Microsoft Office with Windows, not all applications are free. One in particular that DSM requires payment for after a certain point is Surveillance Station. You can only run up to 2 cameras for free on Surveillance Station, after that you need to license Surveillance Station per camera (and despite what some incorrect reviews have stated) purchased camera licenses are transferable to other Synologies. I've done it. Further, if you can't find the application you want Synology also offers Docker so that you can add generic 3rd part apps if they are available in Docker containers. I have 10 apps installed that way and start/stop them as necessary. DSM and any installed application can work across any system volumes that DSM is aware of. Adding the DX1517 is simple: be sure everything is powered off, the disks are installed in the expansion unit, the eSata cable is inserted correctly and tightly screwed in on both ends, and then turn everything on. Magic, you have more disks. In DSM, create a new volume on the new expansion disks. It'll then do a consistency check the volume and then you're good to go. Done. So with this, I now have 50TB spread across the main and expansion unit in two volumes each in RAID 6. Yes, out of 10 disks I'm "wasting" 4. Read on. Here is the key: DO NOT SPREAD A VOLUME ACROSS eSATA CONNECTED DEVICES. I run a separate volume on the expansion unit (all, and I mean ALL, storage vendors strongly recommend that setup) so I have 2 volumes, one on the main DS unit, one on the DX unit. DSM doesn't care, and I certainly don't have a database or anything that needs more space than a single volume. Can you have only a single volume spanning devices? Sure you can. You can also drive most cars manufactured today over 100+ mph. But here's the difference: running a volume across an eSATA connection is like you ONLY being able to drive your car over 100mph ALL THE TIME. When (not if, but when) something goes wrong (which might be your own error, might not), the consequences sort of suck. RAID 6 only allows 2 disks redundancy. If I only had a single volume across my DS and DX and anything were to happen to either my DS, my DX, the power cords going to either, or the eSata cable connecting them, I'd lose 5 disks in the volume. So if I had one volume across both devices, that volume would lose 5 disks. 5 disk > 2 disks. RAID 6 isn't going to help much. Good luck. (For the purists, depending on the nature of the failure there is an outside chance that I could be able to re-establish read-only access to the volume if I can get all drives spinning again. But what would I rebuild 50TB onto ???) So TL;DR: the expansion unit just is and just works. It's transparent, and so long as it's installed correctly, I don't even think about it. I just interface with DSM. Second, Product Life-Cycle Synology does an amazing job of keeping DSM and the core Synology Applications not only up to date for security and reliability issues but they actually increase functionality over time as you own your product. They don't just do that for the first year or while the product is under warranty - but so far for the DS+ series about 5 years or more after the product comes to market. This is a huge plus. Many companies put out a decent product then rush to develop another product they can sell and leave the previous products with old, buggy and insecure firmware. After awhile, what had been a decent product initially becomes incompatible, insecure, and effectively unsupportable (many lower-end phone vendors running Android do this - they simply don't offer updates when they're focused on their next product. Synology product life-cycle record has been first rate. Will it continue to be? Who knows, but the best indicator of future success is past success. Thirdly, Product Support. Storage device support is and should be centered around preventing data loss. I have first-hand experience with Synology live support on a DS1511+ I used to have. Superlative support: I had power problems in my house resulting in my DS being forced to restart repeatedly and ending up not being able to boot from disk. Contacted Synology support, within a day a human being actually manually logged into my system, un-messed it up, and I was good to go. Here's the kicker: the DS1511+ was out of warranty at the time, and they were aware of that. I was and still am impressed. Find another < $1,000 product that will do that. Then find one that will do that when the product is out of warranty. This kind of support is only even remotely feasible if the company keeps the products up to date - meaning, if the underlying product life-cycle is solid. Synology delivers here. I have to comment about the guy going all over Amazon screaming that they won't support the hardware product after the warranty period. First, Synology's base warranty is 3 years. Second, Synology offers extended warranties of 2 years if that's what you want, so you can get 5 years warranty. Finally, it's usually preferable and in the long run cheaper to replace a 3+ year old failed device than it is to get it fixed, particularly at these cost points. It depends what goes wrong: fans, PSUs are easily fixed by local talent. More than that, and even for a PC I'd recommend getting a replacement device. The old drives will work with the new device. If you're worried about Synology SHR RAID, just use RAID 6. Then you can go to any Linux-based device. But if you get a replacement Synology, just slot the drives in, boot it up and you'll be good to go. For a storage vendor, I'm happy if they prioritize data loss issues for real support. If I want help setting up Photo Station et al, there is a solid ecosystem in place for getting help both on the Synology web-site (forum, wiki) but also on other locations (reddit, SynoForum, etc). Overall, I still give Synology 5 stars. ... show more
Reviewed in the United States on December 17, 2019 by Joseph Luke

  • It is an expensive branded SATA enclosure
Style: Unit
As others have said, you are paying a premium for a a single bus eSATA expansion that fits certain Synology NAS boxes. It works well, and the causes no issues with any of the Synology DSM software. That is a huge plus. Everything else is either neutral or a minus. First, you are limited to the bandwidth of a single eSATA bus per expansion box. That means your maximum transfer rate is about 600 megabytes per second period. If you are dealing with small files, or lots of random access, the speed is even slower. If you want to speed things up, you need to add cache drives to the bays of the expansion unit. Synology allows you to share the NVMe cache in the parent NAS, but you risk a RAID crash if you lose your data connection or have a bad shutdown. If you choose to use bays for your cache you are limited to 4 expansion bays and one read only cache or 3 expansion bays and a read / write cache. Once again, you are still limited to the bus speed, but SSD SATA cache drives are faster than traditional drives. You will speed up file transfers by 15%+ with SSD read / write cache. Second, you are paying a fair amount for what is really nothing more than a branded eSATA RAID box. It is nice that out of the box, it works, but it is rather expensive for what it is. Finally, it is nice that the NAS you plug this into controls the expansion just like your NAS. It is really easy to maintain, expand and every other function your RAID. That is the best reason to purchase an expansion versus adding a non-branded eSATA or USB solution to your NAS. Do I recommend this if you need to expand your storage and speed isn't a premium? Yes I do. ... show more
Reviewed in the United States on February 28, 2023 by Amazon Customer

  • Nice way to expand
Style: Unit
I was using one 14TB drive for video storage in my current DS1621xs+ unit and wanted more. I decided I would double my storage, but I wanted to ensure speedy access. The DS unit I had would not let me go from a single drive to a striped array, but it would let me go to a raid 5. I powered down the system and I took the current WD 14TB Purple drive out of my DS, put it in my new DX517 along with two more matching 14TB drives, and powered everything up. My DS unit recognized my old drive and also asked me what I wanted to do with the new drives. I simply selected modify array to raid 5, hit start and waited. I had access to all of the information on my old drive through the entire process, which is very good, because it took a lot of time; going from almost 13TB of full drive data to just over 25TB of capacity took about a day for stage 1, then another day and a half for stage 2; all of my data was intact. After I was all done, I did a speed test to the new array and was very happy with a peak speed of 1.06 GB/s across my network; I run a 10Gb backbone and connections from my PC to the DS unit. This was very expensive, but I am very happy with the performance and ease of this upgrade. I have another, older DS unit and I am planning on adding a DX517 to that unit as well; all of the drive bays are full, and I need more room. I would recommend the DX517 for it ease of use and performance, but the cost is a bit extreme for what is basically a power supply and a E-SATA external housing. ... show more
Reviewed in the United States on January 24, 2023 by David C. Harris

  • Wow, so easy to use
Style: Unit
I already have another Synology Diskstation, but I quickly filled it up. After quite a bit of research, I found this expansion case, purchased it, along with four new 16 TB drives. I decided to leave the fifth bay empty for now. I plugged this expansion into my other diskstation, added the physical drives, then using the Synology user interface, added the four new physical drives to the logical unit, which was already running RAID 6. Since I was doubling the number of drives on an existing RAID, it took many many hours to rebuild the RAID, but it was certainly worth it in the long run. ... show more
Reviewed in the United States on June 16, 2023 by Anastasia

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