Let me tell you why I bought a NAS 🙂 I have been using external hard drives for backups for long years. My wife currently backs up her ThinkPad laptop whenever she sits down at her desk and remembers to connect the external drive with her laptop. I am working with an external 3,5″ USB WD drive as backup solution for my Macbook Pro 2016 since two years. Earlier on I had the same solution for my Thinkpad laptop running Windows 10. This external drive is connected to my MacBook via a docking station and every time I connect my Mac the backups starts automatically, which is very handy.
I know that this is not an optimal strategy. One laptop and one external hard disk is ok but not very secure. In addition once every one or two years I take my backup drive and store it at a relatives house and buy a new one so I always have an elder backup outside my house.
One thing always disturbed me: the close proximity of the backup drive to my laptop. Mac OS every hour starts a Time Machine backup which makes the external hdd spin up very loud and disturbed me, especially at night. So I thought about moving the hdd further away from me and researched the NAS technology.
The hardware
Because I am a beginner I did not want to spend lots of money and started small. I chose a 2-bay-NAS although a NAS with 3 or four drives makes for a much safer backup solution. But I first want to try things out. After researching the differences between Synology and QNAP I decided to buy a Synology NAS because I really liked the easy configuration and the good web interface of this NAS. I do not plan to run anything like a Git server or some downloader on the NAS, so it does not need lots of power and can be cheap. Filesystems like BTRFS that provide more security for the data and need a potent cpu and much main memory will be tested when I switch to a bigger NAS in the future. That is why I bought a cheap Synology-DS 216J NAS.
Here are pictures from this NAS. Please click on an image to enlarge it:
Then I had to decide which hard disks I would want to put in it. I read lots of recommendations for WD Red drives or Seagate IronWolfs. But they are quite expensive. So I decided to extract the hard disk out of my external Western Digital MyBook 3,5″ enclosure and from another elder enclosure which provided me with one 5 TB Western Digital Blue drive and one 3 TB Western Digital Green Drive.
I know that putting two drives of different size and type is not a good backup solution but for now it works. I mounted both drives into the NAS, started the NAS, connected to the NAS via its easy to use web interface and configured the 3TB and 5 TB drive as Synology Hybrid RAID with one-drive-fault-tolerance. Sadly the remaining space between 2,7TB and 5TB on one of the drives went to waste bacause Synology does not support using the extra space for something else 😦
The Synology software is informing me once a week via Email about the current health state of my drives so that I can react when one of the drives degrades.
Setting up the NAS for access for Windows and MacOS
The next step was to setup the NAS for access via Bonjour, AFP and SMB to make it connectable for Windows and Apple machines. There is lots of tutorials on the web available on how to do that, so I won’t go into more detail here:
Then I created a Volume für Time Machine and one for normal data and everything was done. I could backup my MacBook and could also access files from a data partition from Windows and from MacOS.
Performance comparison vial WLAN and LAN
I wanted to know how large the throughput of the NAS would be via WLAN and LAN and also measure the performance differences imposed by the SMB and AFP protocols.
I wanted to find out if a backup via WLAN is practicable. My Time Machine backup takes from 200MB to several GB. Is it practical to do this via WLAN or should I stick to LAN?
The two WD drives deliver about 150 MB/s transfer rate via USB 3.0. So, combined, they could in a best case scenario deliver about 300MB/s. But the Synology NAS only offers a 1 GBit LAN port. So the maximal throughput of two hard drives would be severly capped by the NAS LAN interface to about 120MB/s in the best case! The built in processor of the NAS also plays a role in how fast it can deliver data. Other factors like encryption and pcrocessor hungry file systems like BTRFS also play a factor in the NAS throughput.
The next limiting factor for performance if you want to deliver data via your WLAN router is how fast the WLAN router can distribute data wirelessly.
In order to find out what I can realistically expect, I created a mix of 27.000 files to test a realistical throughput of lots of documents, pictures, etc. and one big 31 GB big file to test how performant the transfer of big files is.
I tested the following scenarios:
- direct transfer via one of my WD HDDs in a external enclosure before I put them into the NAS
- then I put one HDD into the NAS and did my tests
- then I put both HDDs in Synology Hybrid RAID mode into the NAS and did my tests
- I tested vial LAN how big the transfer rate difference between SMB and AFP is
- at last I tested how fast my FritzBox 7490! can transfer data via a 5GHz 802.11ac WLAN from the NAS to my computer by using the AFP protocol
As a result you can see:
- that in my special case the transfer from data to a WD HDD via HDD is unsurprisingly the fastest method.
- when transferring data via LAN to the NAS it did not really make a noticeable difference if the NAS contained one or two HDDs
- that the transfer via AFP is significantly faster than SMB on Macs
- that the transfer via WLAN is the slowest possibility of all scenarios
That is why I do backups mostly when my Macbook is connected to its dock via LAN. But I still can use WLAN backups when using my MacBook somewhere else in my appartment.
| one 31,02 GB file | 26.486 files with 26,7 GB total filesize | |
| Direct transfer from MacBook pro internal SSD to WD Green via USB 3.0 | 4:03 min (154 MB/s) | 4:22 min (104 MB/s) |
| LAN transfer to NAS which contains only 1 HDD via SMB | 7:55 min (67 MB/s) | 15:36 min (29 MB/s) |
| LAN transfer to NAS which contains only 1 HDD via AFP | 6:30 min (118 MB/s) | 11:37 min (39 MB/s) |
| LAN transfer to NAS which contains 2 HDDs via SMB | 8:05 min (65 MB/s) | 16:05 min (28 MB/s) |
| LAN transfer to NAS which contains 2 HDDs via AFP | 6:51 min (93 MB/s) | 11:40 min (39 MB/s) |
| WLAN transfer to NAS which contains 2 HDDs via AFP | 10:29 min (51 MB/s) | 23:33 min (19 MB/s) |
Ioannis Karagiorgos blog 