TLDR: As an experienced user of data storage products, I'm impressed with Synology, particularly the DX1517 expansion unit. Its integration with the DS1517+ was seamless, offering robust functionality and reliable RAID 6 setup. The device's ease of setup and DSM's versatility stand out, though I advise against spanning a single volume across connected devices for safety reasons.
Having spent decades both professionally and personally dealing with data storage, I've come to appreciate quality products. Synology, which I've been using for almost a decade, has consistently met and exceeded my high expectations.
When evaluating a product, I consider three key metrics: the product itself, its lifecycle, and the support available. Focusing on the Synology DX1517, which I added to my DS1517+ at my home office, I'll discuss my experience with it, keeping in mind these criteria.
First, the Product:
The DX1517 expansion unit was straightforward to integrate with my existing DS1517+. Synology's products are based on the Linux-driven DSM, or Disk Station Manager, which I find to be extremely powerful for home/small office environments. DSM offers robust base functionality, enhanced by a wide range of applications from both Synology and third-party vendors. While many of these apps are free, some, like Surveillance Station, require payment after a certain point.
I added the DX1517 easily. It required powering everything off, ensuring the disks were in the expansion unit, and securing the eSata cable. Once powered on, it was a simple process to create a new volume on the expansion disks in DSM.
I now have 50TB across the main and expansion units in two separate volumes, each in RAID 6 configuration. It's crucial not to spread a single volume across eSATA-connected devices, as it risks the entire volume if there's an issue with one of the units or the connecting cable. In RAID 6, only two disks redundancy is allowed, so spreading a volume across both devices would risk significant data loss if more than two disks fail.
Second, Life Cycle:
From my experience, Synology products are durable and reliable over the long term. The DX1517 has proven to be no exception, continuing to function effectively without issues.
Third, Support:
Synology’s support has been adequate. While I haven't had significant issues requiring their assistance, it's comforting to know that help is available if needed.
In conclusion, the Synology DX1517 is an excellent addition for anyone needing expanded storage. It's user-friendly, reliable, and integrates seamlessly with existing Synology systems. My advice to potential users is to be cautious with how you configure your volumes and understand the limitations of your RAID setup.
Add a debit or credit card to save time when you check out
Convenient and secure with 2 clicks. Add your card
Top rated similar items
Page 1 of 1 Start overPage 1 of 1
From the manufacturer
Synology 5bay Expansion Unit
- 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.
- 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.
- 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.
- 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.
Compare with similar items
This Item  Synology 5bay Expansion Unit DX517 (Diskless) 157 mm x 248 mm x 233 mm |  |  |  |  |  | |
| Price | — | $1,799.99 | $294.99 | $1,099.99 | $369.99 | $118.57 |
| Delivery | — | Get it as soon as Sunday, May 12 | Get it as soon as Sunday, May 12 | Get it as soon as Sunday, May 12 | Get it as soon as Tuesday, May 14 | Get it May 13 - 15 |
| Customer Ratings | ||||||
| Storage Capacity | ||||||
| User interface | ||||||
| Tech Support | ||||||
| Value for money | ||||||
| Sold By | — | Amazon.com | Amazon.com | Amazon.com | Amazon.com | Deal Targets |
| size | 157 mm x 248 mm x 233 mm | DS1823xs+ | DS224+ | 270 mm x 300 mm x 340 mm | DS423 | 1-bay; 512MB DDR3L |
| compatible devices | Desktop | Server | Laptop, Smart Phone, Desktop | Server | Desktop, Laptop, Server, Smart Phone | 3.5 SATA HDD 2.5 SATA HDD (with optional 2.5 Disk Holder) 2.5 SATA SSD (with optional 2.5 Disk Holder) |
| assembly required | ✗ | ✓ | — | — | ✓ | — |
| weight | 8.62 pounds | — | 1.3 kilograms | — | 2210 grams | 0.88 kilograms |
Reviews with images
Joining to my DS918+
I recently installed a DS918+ and have been very impressed with the speed, management tools and Plex performance. Having migrated off an older NAS, I had hard drives laying around, so logically I needed this!The retail packaging with handle came inside a Synology type warehouse box fully taped and that was nested inside a larger Zon box with a ton of paper packing around it. Nicely done there.Set up was easy. The cable is custom for the Synology connectors and only about 18 inches long, so you need to store them alongside or very close to each other. I have them on separate shelves on a wire rack vertically and it reaches fine (hopefully the pic is approved for your review).Similar to my DS918+ review, the unit is very light until you put drives into it, but it's not a cheap feel. This one has distributed lights over each bay. The master NAS has lights running down the side. I may need to hit the forums to see if I can mute or turn those off. The drive trays are spring loaded and only took just a few minutes to mount a couple of disks. When re-inserting the tray into the NAS, be sure to not have the spring loaded cover already pressed, it won’t fit snugly nor mount the drive properly. No danger here just have to click it out and slide it in then lock it in place. Power it up.Once attached to a supported NAS device for management, you go to that units web interface. I didn’t have to take any action, but could see from the dash board on the ‘desktop’ admin tool that it had additional drives available. So I launched Storage Manager right away. On my base NAS I created a straight Raid 5 volume. For this set of disks, I'm testing "Disk Group" running SHR, Synology's proprietary raid solution. The biggest thing you can get out of SHR over a typical raid with single disk protection is you can keep adding hard drives. Since this is 5 bays, I started with 3 4TB drives and the usable space is about 7.4 TB. After I move some data around, I'll add another 4TB and expect right at 11 total... then test adding another drive and will report back here the result. Please note if the drives are of varied sizes, my understanding is that it will round down to the lowest drive size. So 1 4TB and 1 2TB SHR’d would be the same as 2 2TB drives. Plenty of cool YouTube vids to explain better for you.After you create your disk group, you go to the Volume tab and do a “Create” from the menu up top. Next you’ll want to see that storage right away (it’s doing a disk check but the space is usable rather quickly). Launch File Manager and create a new share. Set up the name, security all that and you are ready to rock.I’ve got a lot of juggling to do but will do some speed tests soon. So far Volume to Volume tests seem really fast which is great, but not sure that will be the primary access use case.Check out the DS918+ reviews on the user interface and positives there. Over all I am very pleased with the expansion.
Top reviews from the United States
There was a problem filtering reviews right now. Please try again later.
Reviewed in the United States on October 25, 2017
Style: UnitVerified Purchase
I recently installed a DS918+ and have been very impressed with the speed, management tools and Plex performance. Having migrated off an older NAS, I had hard drives laying around, so logically I needed this!
The retail packaging with handle came inside a Synology type warehouse box fully taped and that was nested inside a larger Zon box with a ton of paper packing around it. Nicely done there.
Set up was easy. The cable is custom for the Synology connectors and only about 18 inches long, so you need to store them alongside or very close to each other. I have them on separate shelves on a wire rack vertically and it reaches fine (hopefully the pic is approved for your review).
Similar to my DS918+ review, the unit is very light until you put drives into it, but it's not a cheap feel. This one has distributed lights over each bay. The master NAS has lights running down the side. I may need to hit the forums to see if I can mute or turn those off. The drive trays are spring loaded and only took just a few minutes to mount a couple of disks. When re-inserting the tray into the NAS, be sure to not have the spring loaded cover already pressed, it won’t fit snugly nor mount the drive properly. No danger here just have to click it out and slide it in then lock it in place. Power it up.
Once attached to a supported NAS device for management, you go to that units web interface. I didn’t have to take any action, but could see from the dash board on the ‘desktop’ admin tool that it had additional drives available. So I launched Storage Manager right away. On my base NAS I created a straight Raid 5 volume. For this set of disks, I'm testing "Disk Group" running SHR, Synology's proprietary raid solution. The biggest thing you can get out of SHR over a typical raid with single disk protection is you can keep adding hard drives. Since this is 5 bays, I started with 3 4TB drives and the usable space is about 7.4 TB. After I move some data around, I'll add another 4TB and expect right at 11 total... then test adding another drive and will report back here the result. Please note if the drives are of varied sizes, my understanding is that it will round down to the lowest drive size. So 1 4TB and 1 2TB SHR’d would be the same as 2 2TB drives. Plenty of cool YouTube vids to explain better for you.
After you create your disk group, you go to the Volume tab and do a “Create” from the menu up top. Next you’ll want to see that storage right away (it’s doing a disk check but the space is usable rather quickly). Launch File Manager and create a new share. Set up the name, security all that and you are ready to rock.
I’ve got a lot of juggling to do but will do some speed tests soon. So far Volume to Volume tests seem really fast which is great, but not sure that will be the primary access use case.
Check out the DS918+ reviews on the user interface and positives there. Over all I am very pleased with the expansion.
The retail packaging with handle came inside a Synology type warehouse box fully taped and that was nested inside a larger Zon box with a ton of paper packing around it. Nicely done there.
Set up was easy. The cable is custom for the Synology connectors and only about 18 inches long, so you need to store them alongside or very close to each other. I have them on separate shelves on a wire rack vertically and it reaches fine (hopefully the pic is approved for your review).
Similar to my DS918+ review, the unit is very light until you put drives into it, but it's not a cheap feel. This one has distributed lights over each bay. The master NAS has lights running down the side. I may need to hit the forums to see if I can mute or turn those off. The drive trays are spring loaded and only took just a few minutes to mount a couple of disks. When re-inserting the tray into the NAS, be sure to not have the spring loaded cover already pressed, it won’t fit snugly nor mount the drive properly. No danger here just have to click it out and slide it in then lock it in place. Power it up.
Once attached to a supported NAS device for management, you go to that units web interface. I didn’t have to take any action, but could see from the dash board on the ‘desktop’ admin tool that it had additional drives available. So I launched Storage Manager right away. On my base NAS I created a straight Raid 5 volume. For this set of disks, I'm testing "Disk Group" running SHR, Synology's proprietary raid solution. The biggest thing you can get out of SHR over a typical raid with single disk protection is you can keep adding hard drives. Since this is 5 bays, I started with 3 4TB drives and the usable space is about 7.4 TB. After I move some data around, I'll add another 4TB and expect right at 11 total... then test adding another drive and will report back here the result. Please note if the drives are of varied sizes, my understanding is that it will round down to the lowest drive size. So 1 4TB and 1 2TB SHR’d would be the same as 2 2TB drives. Plenty of cool YouTube vids to explain better for you.
After you create your disk group, you go to the Volume tab and do a “Create” from the menu up top. Next you’ll want to see that storage right away (it’s doing a disk check but the space is usable rather quickly). Launch File Manager and create a new share. Set up the name, security all that and you are ready to rock.
I’ve got a lot of juggling to do but will do some speed tests soon. So far Volume to Volume tests seem really fast which is great, but not sure that will be the primary access use case.
Check out the DS918+ reviews on the user interface and positives there. Over all I am very pleased with the expansion.
Images in this review
Top reviews from other countries
R. Caron
Installs without a hitch
Reviewed in Canada on February 7, 2024Style: UnitVerified Purchase
José Moisés Fernández Rojas
Hermano menor genial
Reviewed in Spain on November 5, 2023Style: UnitVerified Purchase
Francisco Lopez
Super Erweiterung
Reviewed in Germany on February 25, 2023Style: UnitVerified Purchase
Francisco Lopez
Reviewed in Germany on February 25, 2023
Zusätzlich ist es dann auch Recht leise, die Erweiterung ist nämlich schon Recht laut wenn 5 große Festplatten darin arbeiten 🙄
Images in this review
Julien b.
Synology toujours au top
Reviewed in France on January 21, 2023Style: UnitVerified Purchase
Bakur Alhujaili
it's good deal
Reviewed in Italy on December 17, 2022Style: UnitVerified Purchase
Bakur Alhujaili
Reviewed in Italy on December 17, 2022
Thank you Amazon.it
Images in this review
