If you read my lab posts or talk to my about lab gear it’s no secret that I’m a fan of Synology NAS boxes and for good reason. I personally bought two, a DS1010+ for my vSphere lab and a DS1511+ for lab, media, and home storage/backup. They have both been nothing but reliable…true workhorses. The only time I’ve had to do anything to them is when I had to reboot the DS1511+ for showing that a slot was bad. The reboot cleared it and when filing a bug report I saw I was running beta code that I had forgotten to upgrade months ago so I chalk that anomaly to that until proven otherwise.
Over the last year as I’ve kept up with Synology they’ve impressed me with several things that they did. I’m a Mac user…and when OSX Lion came out it broke Time Machine backup on most third-party NAS devices due to a change in authentication. Synology was quick to put out a beta of new code to fix it. Yes, it was beta but they did it quickly as it caught many people off guard. They also back-ported the patch to fix support for Time Machine to older models that are out of support. Very customer focused. With the latest release of the Synology OS (DSM 3.2) they increased performance on many ARM CPU based models by up to 19%.
Recently Synology sent me a DS212+ to play with and review. Actually, they asked what I wanted and since I’ve been working on a small lab build for Varrow employees I wanted to try their newest 2-bay unit. Not everyone wants to or can afford to start with a 5-bay device and with the current price (late ’11/early ’12) of drives it gets expensive real fast to fill up a larger NAS box so I thought the DS212+ was a good choice.
A quick note about Synology model numbers. They might seem confusing at first but once you learn the format they make a lot of sense. DS is Disk Station, which are their desktop form factor NAS boxes. The first number, in this case 2, is the number of drive bays. The second number is the model year, so 2012. The symbol after the number is:
The DS212+ is a powerful little NAS, and that’s why I chose to look at it first.
This box has a fast 2GHz ARM CPU and 512MB of RAM. Unlike its larger cousins that I have you cannot add more memory to this system, but I have yet to see a need to do so. My other Synology NAS were upgraded to more memory (3GB) but I mainly did that because it was very cheap to do so and I figured it was never a bad thing to add more cache memory. Keen eye’d readers may notice that there is no SATA III support yet, but since you’re mainly limited to network throughput I don’t see this as a problem. Being the + model Synology did add USB 3.0 support to this device and I got some USB 3.0 drives to play with and test.
It’s a Synology and if you haven’t played with one the initial impressions are usually very good. Nice packing with thoughtful inclusions such as Ethernet cables and a very simple getting started guide. In the box is a disc with the tools you need to get your new NAS online, but I suggest you do what I do and go download the latest from their site. The DS212+ has the newer black look and I like it a lot. The older Synology units could be ugly but this one is sleek. It’s also very quiet, which is another plus for these devices. My lab is in my home office and I rarely ever hear the two larger NAS and this one is very quiet as well. Any real noise comes from your choice of drives, not the devices.
The process to setup a new Synology is the same across all models. Unbox the system. Install your disks. Plug in network. Plug in power. The drive carriers for the DS212+ are nice, but plastic. I always worry about breaking these. I like the unlock mechanism better than the one used by my larger devices. All of the drive carriers I’ve used from Synology have rubber bushings, which I like a lot. I hate vibration noise from hard drives and I haven’t seen that at all with these.
Once everything is physically installed you just power on the Synology, wait for it to boot, and then use the Synology Assistant to find the device. Note that these expect a DHCP server on the network. Once the Assistant app (and there is one for OSX as well as Windows) finds your new NAS you have it install the latest DSM operating system. DSM, DiskStation Manager, is the operating system that runs on all of the Synology devices and some people are surprised that it’s not installed on there already. DSM lives on your internal disks in a special partition, which is why the NAS cannot be preloaded. Once the initial configuration/deployment is done you are ready to go.
My goal is to do a writeup/review on DSM in the near future. One very big feature of Synology devices is the fact they all run DSM so configuration, management, and monitoring of the DS212+ is exactly the same as my DS1010+ and DS1511+. If I don’t look at the address bar in my browser I can’t even tell which one I’m managing. DSM has a lot of really features. There are many little things that make it powerful, not just the major features. For example, from the file browser GUI in the management console I can remotely mount another network share which lets me quickly and easily move files between network devices without “bouncing” them off another system. You can also schedule data backups from one Synology to another. Again, I hope to do a good writeup on DSM in the very near future…especially now that DSM 4.0 Beta has been released.
While not really important on a two-bay device since you’re going to do RAID 0, 1, or JBOD, the larger devices support Synology’s Hybrid RAID or SHR. The idea with SHR is that you can mix, match, and add drives over time and get the best usage out of your configuration while also getting N+1 protection from a disk failure. Other NAS devices have similar options but it’s an interesting option if you plan to change drives later or not fill a cabinet right away. For more detailed information on SHR check the Synology wiki page here.
As I just mentioned, all Synology boxes run the same DSM code. This, at least to me, means that even the devices that are not on the VMware HCL should still work fine…they just haven’t been submitted for testing and so far the DS212+ has proven me correct. It works just like my other boxes…just not as fast since it doesn’t have five spindles for handling I/O. These support NFS and iSCSI for vSphere datastores and I primarily use NFS for several reasons. The big one being that I can mount the datastores directly from my Mac systems.
The only downside to that is that you cannot thin provision VMDKs on NFS. That’s one feature I’d really like to see. I’d also like to see NAS VAAI support but that’s a big ask from me on these devices. Give me thin provisioning first.
NOTE: I had said that the Synology didn’t support thin provisioning with NFS but that is incorrect as Julian noted in the comments. I tested it on two of my NAS boxes and it works fine. It shows the full file size in the directory listing but free/used is correct. Honestly, I’m not sure why I was thinking it didn’t…I just thought it wouldn’t when I first deployed the DS1010+. My apologies for the mistake.
There are some catches when using external (USB) drives, though. They are treated as independent drives and automatically shared out when connected. You can’t use a fast USB 3.0 drive to extend the internal volume nor can you RAID 1 or 0 a pair of USB 3.0 drives. You plug in a 3TB USB 3.0 drive and it shares out a 3TB volume. While you can share out the USB drives via NFS and use them as datastores you cannot create an iSCSI volume on them and use that. Unfortunately I don’t have an eSATA enclosure to test with but I assume it is the same. If so, and you are worried about just two spindles, you may want to consider the DS712+ which is a 2-bay unit that can take the external DX510 5-bay expansion. It’s a little more money but probably worth it later. I personally feel the DX510 costs too much…but I haven’t had the chance to work with one yet.
While working with this device I’ve run a number of benchmark tests using Iometer. The bottom line is this… Choose the correct disks for your workload. If this is going in your vSphere (or other environment) lab I suggest you buy good 7,200 RPM drives. If you plan to use this for archive/backup/media use more power efficient, quieter, green type drives. That’s the split I have in my DS1010+ (1TB WD Blacks) and DS1511+ (2TB Seagate LPs). In the DS212+ right now I have a pair of 1TB Seagate Barracudas. Not the latest and greatest, but again the HD shortage has hurt me on available gear. The DS212+ had no problem maxing out its Gb Ethernet connection when doing sequential work. Add in random tests and it would drop down, but that all depends on your spindles, block size, and randomness of the requests. For a vSphere lab it’s all about the IOPS. The only time I usually max the throughput on a Gb link is when doing a clone or deploying from a template. The rest of the time my links are not saturated and it’s all up to the drives delivering IOPS. If you want a really fast two-bay device you may consider using SSDs instead of spinning disks, depending on the space requirements for your lab. If you do this you may consider using iSCSI instead of NFS since you can thin provision with that.
The USB 3.0 performance wasn’t as good as I was expecting, though. I am using a WD 3TB external and a Seagate GoFlex 3TB. Anandtech reviewed the Seagate drive here and got >150MB/sec sequential performance. For the first test I simply took the drives out of their boxes and plugged them in. The DS212+ had no problem mounting the pre-formatted drives and sharing them out. But…with Iometer the best I could get was about 40MB/sec, well below the 100MB/sec I was hoping to see over the network. It’s pretty much operating at USB 2.0 speed.
To try and improve this I had the DS212+ reformat the drives as ext4, which is a very common Linux filesystem. If you’re not aware, the Synology devices run their own distribution of Linux. After formatting the drives I ran the same Iometer test again and this time I saw speeds around 70MB/sec over the network. Performing a copy from the USB 3.0 drive to the internal disks in the DS212+ I saw the same speed. You can do this test by enabling shell access in DSM and then sshing in to the device. This tells me two things. First, there was very little difference between internal copies and network copies. Second, it’s still not as fast as I’d like it to be. Now I am basing my opinion on Anandtech’s numbers. Being a Mac user I don’t have a single USB 3.0 port available to me at home or in my Varrow labs. 70MB/sec is more than you can get with USB 2.0, but not maxing out a Gb link. I suspect that these early USB 3.0 chipsets are not all equal and things can and will improve in the future.
A common question I get is about bottlenecks in these NAS devices. Everything is done in software…so it’s a good question. To me, it appears that Synology does a good job of overbuilding their devices, especially the performance models. The above picture shows the Resource Monitor CPU graph when doing 4K writes, 100% Random to the internal disks and external USB. It maxes at 20% CPU. There is a LOT of headroom there. What can you do with that headroom? Use the other cool features in DSM or add your own applications. These boxes can do a lot more than simple file sharing. More to come in a DSM post.
I don’t show it but memory utilization during this test was flat at 11%. Again, headroom. This unused memory will be used for caching and in my lab I enable async mode for NFS so I get write caching as well. If you do this make sure you have the Synology on a UPS device to reduce the chance of data corruption should you lose power.
There really isn’t anything bad to say about the DS212+. The price may be a bit more (~$475 at time of writing) than some want to spend on a 2-bay unit but it’s a very powerful and flexible NAS. External connectivity with USB 3.0 and eSATA is very good. There are less expensive options from Synology (remember, DS212 and DS212j) for basic lab setups which will probably work just fine but if you’re like me you’ll probably find you keep asking the NAS to do more, and more. Just plan accordingly.