Synology DX517 5 Bay Desktop Network Attached Storage Expansion Enclosure, Black

Product Information

Given the high cost of the DX517 (and I presume its rumored, impending replacement will be about the same), I'm wondering what people are using it for. I see some posters noting that they have two, or even three of these expansion units. You can save a few hundred dollars over another NAS unit, and I suppose you don't need to deal with more configuration, but why put money into a DX517 instead of larger drive sizes?

https://forum.polkaudio.com/discussion/180783/digitizing-my-movie-collection-synology-ds-918-nas-review Figure 3. Synology DS918+ NAS (left) and DX517 expansion unit. The DX517 attaches to the DS918+ via an eSATA cable. Anyway, i want to strictly separate the hdd's / storage from the expansion unit from the storage of the NAS to prevent data loss caused by NAS or DX failure. For example if the NAS or DX Powersupply fails or one of them just stops working, the RAID will be damaged, because suddenly several disks disappear at the same time. This is why i want to separate them. Unfortunately, it is not clear to me how to set it up the right way. I am not sure, if i have to create a separate storage pool with its own volume(s) for the new disks in the expansion unit, or if it will be enought to simply add the disks to the existing storage pool and create a new volume within this storage pool? I think the second option (adding drives to existing pool and creating a new volume in there) will distribute the data from volume 1 and 2 which are in the same storage pool, across all HDD's (These in the NAS and DX517) and will not separate them physically on the Harddrives, right? Performance figures are obtained through SMB sequential throughput tests using Windows Server 2016 Datacenter on a This may be one of those cases of "if you have to ask, it's not for you," but I raise the question mostly because I still really like the idea of the expansion unit and still think it might be something I could make use of - I'm just trying to recalibrate my expectations and figure out if it's still something that could be useful for me.Synology SNV3400 series M.2 NVMe SSD drives can be installed through the built-in M.2 slots to enable SSD caching or create SSD storage pools. Drives are sold separately. I upgraded from a Drobo to a ds1621+ a few months ago and it has been great! I made what seems to be a common mistake (given other posts here) and assumed that the DX517 expansion unit would seamlessly give me another five drive bays for when I was ready to expand. I have accumulated a number of hard drives in the process of upgrading and like the idea of putting them to use, but in reading about the DX517 it seems it'd be fine to create a second storage pool, but it's extremely risky and poor practice all around to spread your volume between the drives in the main NAS unit and drives in the expansion unit. This sub has talked me out of that idea - I don't want to risk it. The storage space on my Synology NAS (DS1520+) is running out. That's why I bought an expansion unit (DX517). Now I saw your video on youtube called "Understanding the Pros and Cons of the Synology DX517 Expansion - Part I". Unfortunately, part II and III have not been released yet. (Hope they will in future). I am sure that you may would have answered my question in video part 2 or 3.

I have not noticed any speed or performance differences when loading files into the expansion unit or when streaming video from the expansion unit. In two years time, the NAS's 45% storage vacancy had dwindled to 19%. I thought it would be wise to proactively increase storage space. My first thought was to replace the DS918+ with a Synology eight-bay DS1819+ equipped with 10 TB Western Digital Red drives. In two year's time, the format distribution of my video collection had changed to 44% DVDs, 51% Blu-rays, and 5% 4K Blu-rays. This redistribution was due largely to replacing DVD titles with their Blu-ray versions and replacing Blu-ray titles with their 4K Blu-ray versions, rather than acquisitions of new releases. Over the past two years, many of my favorite DVD titles have been re-released in Blu-ray format with high quality remastering and some of my favorite Blu-ray titles have been re-released in 4K format. Sequential write throughput in MB/s when using a 10GbE SMB connection. Tested on an all-flash volume with Synology SAT5200 flash drives. SSD cache can be enabled by using 2.5" SATA SSD drives in standard drive bays or without occupying drive bays by installing Synology SNV3400 Series M.2 NVMe SSD drives through the built-in M.2 slots. SNV3400 Series M.2 NVMe SSD drives can also be used to create SSD storage pools. Drives are sold separately.Usable capacity for each volume will be lower than the maximum volume size and is dependent on the filesystem and the amount of system metadata stored.

PCIe add-in cards, expansion units, and storage drives are sold separately. Refer to the compatibility list for compatible devices. My Synology DS918+ NAS was set up in February of 2018 with four 8 TB Western Digital Red drives. My video collection took up 17 TB (55%) of the available 30.7 TB of storage. I assumed the 13.7 TB of free space would last a long time (years) since I only buy a few titles per year. At the time of initial installation, my video collection was 71% DVDs, 29% Blu-rays, and 0% 4K Blu-rays.

Performance figures obtained through internal testing by Synology. Actual performance may vary depending on the testing environment, usage, and configuration. See performance charts for more information.