Syncing Two NAS (Or Computers) To Minimize Data Loss – A BitTorrent Sync Review

If you are a freelancer, an indipendent knowledge worker or you run a small business, BitTorrent Sync may be a better alternative to cloud hosting for your files.

BitTorrent Sync allows you to sync folders (hence, files) between your computers using the P2P protocol. I’ll tell you shortly why this is an advantage and in which situations are particularly favorable to use BitTorrent Sync with one or more NASs.

What you get is essentially faster data access and minimal data loss, since all computers in your LAN will be able to quickly retrieve files in case of need. You also benefit from increased security, because there is no external cloud source to store your files (and thus potentially access them).

Below I explain how to install and use BitTorrent Sync to connect two or more NASs — or two computers — in your network and why you may want to opt for this solution.

How to use BitTorrent Sync to link two NASs

Pick a Linux or BSD version for your NAS, as it’s free and community-supported. The most common distros for the NAS are FreeNAS, NAS4Free or Open Media Vault on your current Debian system.

If you have a Synology NAS, you may want to read the backup tips Arne Preuß of explained here.

Both my laptop and my netbook use Linux-based systems – Arch Linux and CentOS 6.5 – so I’m going to use the Linux version in this tutorial. My computers play the role of two NASs in this case, called NAS1 and NAS2 for convenience.

BitTorrent Sync is easy to install on Linux: just download the right package for your architecture (NAS1 is an x64, NAS2 an i386), extract the .TAR.GZ file to a folder of your choice, open the terminal and type this (customize it with your own paths first!):

cd /home/username/your-btsync-folder/

That will get you to the /your-btsync-folder/ of choice so you can operate in it. That folder contains two files after you extracted the .ZIP file:

  • the btsync executable
  • a License file

Now type in your terminal:


This is a command that executes btsync in the background.

Repeat this procedure on your other computer/NAS.

Syncing two computers with BitTorrent Sync

Once BitTorrent Sync is installed on both NASs, open the web UI by entering the address localhost:8888 in your browser. I did it on NAS2 in the photo below:

BitTorrent Sync is fast!

Your computers/NAS may take a while to connect to each other. Make sure your ports are open on your router firewall, or the computers/NAS won’t sync.

I had this problem when I installed BT Sync on NAS2, because the software didn’t make it to open the port automatically (happens!), so check the router firewall manually — you can generally reach your router admin panel at the address in your browser — and open a port for BitTorrent Sync if necessary.

3 situations to use BitTorrent Sync with a NAS

Whether you decided to use BitTorrent Sync with two NASs or to link a personal computer to a NAS or two computers over a LAN, there are a few situations this solution would wind up beneficial in terms of both data loss reduction and privacy concerns.

Situation 1: You want to keep a local copy and a NAS copy synced

This is a basic situation where you want your files available at any time, not only on your personal computer. Maybe you’re the type who travels a lot or is out for work all day long — I understand, been there done that. :-) Syncing your local copy with your NAS copy allows you to access your files anywhere, as all you need is remote access to your NAS.

Situation 2: You have a work group and you need to sync files between all machines so that everybody can have a copy

Basically, you and your work team would use the NAS as a private Dropbox, with the difference that a NAS (or a computer you use as a NAS) is even faster than Dropbox.

If you run a small business or a noprofit with a handful of employees, contractors and volunteers, this solution allows you to keep everybody up do that and share company files, brochures, software and anything else you need everyone to keep handy to keep things going.

Situation 3: You need a cheap solution to replicate important data

This is the situation when you need two or more NASs in different locations that are synced to each other — if one is faulty, there are other copies available in the other NASs, and since it’s unlikely that all NASs will fault at the same time, the risk of data loss is close to none. Also, the protocol is fast and doesn’t use too many resources per sync.

Situation 3 is more likely to be the situation a typical business find itself into. If you run a company, syncing more NASs will minimize the risk of data disaster and it will make file recovery easy. Since there is no central node, a faulty NAS doesn’t compromise data.

This is an advantage for both business and private solutions and it can be done by using recycled computers as NAS drives.

Pros and Cons of using BitTorrent Sync with NAS/computers


  • Minimize data loss (multiple copies across the computers in the network)
  • Inexpensive architecture if you buy a good NAS or a computer and use a free and open OS
  • Increased security (no external access, everything stays network)
  • Data transfer is fast!


  • Requires some tech savvy skills to setup

All in all, I have to say that my life as a busy freelancer with naughty computers has improved considerably since I installed BitTorrent Sync. Moving work documents and file backups stopped feeling like a chore and I no longer have to rely on remote backups — which proved unreliable in my case, because sometimes the connection comes and goes, so I lost a lot of data with the transfer — and I don’t have to spend nights to copy stuff on my external hard disks only to spend the following night copying everything back in.

Have you tried BitTorrent Sync? If you have, did it help you reduce data loss?

I would love to hear your story. :)