LAN-only sync

[swdrumm2]

I want to restrict BTSync to only those devices connected to my LAN. I'm using a DHCP server, so designating predefined hosts doesn't help.

When I de-select all of the general options except "Search LAN" BTSync works, but very very slowly (50 KB/s). When I enable "Use tracker server" I get solid performance (1 MB/s).

1. Is the tracker server an external host or is it confined to my network?

2. Is the DHT network restricted to my network, or does it look outside on the internet as well?

3. What is the best way to configure BTSync to only work on my LAN?

Thanks.

[GreatMarko]

1. Is the tracker server an external host or is it confined to my network?

External

2. Is the DHT network restricted to my network, or does it look outside on the internet as well?

Outside

3. What is the best way to configure BTSync to only work on my LAN?

Disable Relay, Tracker, and DHT options.

Turning off "Search LAN" should also give you a noticeable improvement in speed, and also changing the advanced setting "lan_encrypt_data" to "false" may also give you a speed boost!

[swdrumm2]

Disable Relay, Tracker, and DHT options.

Turning off "Search LAN" should also give you a noticeable improvement in speed, and also changing the advanced setting "lan_encrypt_data" to "false" may also give you a speed boost!

Got, it thanks. What I don't understand is why BTSync is so much slower without the external tracker server? For comparison, with Unison over SSH, I get 3 MB/s vs. 200 KB/s with BTSync.

Going back to Unison over VPN for now...

[coewar]

Regarding the transfer bandwidth comparison.... when I was observing, I saw that the bandwidth was quite low, however the files actually got moved very quickly. I suppose this is because before transferring data over the wire, BTSync is packing all the piles of files into its 4Meg unique segments? So then it only needs to transfer unique blocks of data.

Is that remotely close? Cause if not, there is some mystical un-monitored network bandwidth. It was showing very small amounts and not even consistently, but it manages to push a lot of data to the other side in a short time.

[swdrumm2]

Not sure...I dumped btsync for my own OpenVPN + SSH solution (with a Raspberry Pi acting as the server attached to a 240GB SSD). Much as I was impressed by btsync, I'm just not gonna trust it until they opensource the code.

[coewar]

Did you create SSH tunnel for BTsync to use? I was trying that several months ago. Going to give it another shot soon.

But wrapping the UDP in the TCP did not work, even though I am wrapping UDP in the TCP over SSH in production for other things.

[swdrumm2]

Nope, just with the privacy options listed above.

[aslamK]

Re: v. 1.1.48 on Linux Mint 15 & Ubuntu 13.04

I find that folders do not connect with their sync counterparts on a LAN if Relay and Tracker servers are not enabled in the following situations:

1. when the folders are first added, and
   
2. after BTSync is started.
   

The folders do continue to sync after disabling Relay and Tracker servers after the initial connect.

Is this expected/intended behavior?

[Harold Feit]

Expected when internet security software is being contrary, but not intended.

[aslamK]

Expected when internet security software is being contrary, but not intended.

OK... So I set the ports on the respective machies to Allow all incoming TCP/UDP -- got the port nos. from Preferences on the web GUI.The GUI now shows that the sync is happening.

The ports seem to get set randomly when the BTSync process starts. Can I configure the port to be from a range of numbers so that I can allow incoming on those ports without having to do so manually every time I launch BTSync?

[aslamK]

After btsync is freshly launched, it's apparently not enough to open up the ports as describe in my previous post. The synching doesn't start until "Use predefined host" is checked, and the other machine's ip:port is added, for each folder; however, this only needs to happen on one of the machines. Once the sync gets going, disabling "Use predefined host" and removing the ip:port does not seem to affect the sync, until btsync is stopped and started again.

This, in addition to having to manually open new ports (and close old ones) after launch, is obviously quite cumbersome.

[aslamK]

Upon looking at the sample config file more carefully, I learned that "listening_port" can be made constant :$ ... (Being able to specify a range of numbers here, would give a degree of randomness to the port no.)

This is fine when if the synching is only within a LAN. However, if 'Search LAN' is checked and the listening ports are open, why do I also need to enable 'Use predefined hosts' and provide the ip:port?

[Harold Feit]

Did you unblock multicast on your network when using search lan?

[aslamK]

Did you unblock multicast on your network when using search lan?

"Multicast Streams" was disabled on the router. I enabled it and rebooted the router. The behaviour remains the same: Folder does not appear as synching on the web UI until I check 'Use predefined host' and add the ip:port on one of the two machines.

[RNAOMDCOLECLTOINOFLERTTES]

"Me too". Without at least the tracker enabled I can't get a Windows machine and a Mac on the same wifi to see each other, tick that option and 20 seconds later they're happily chattering away. Turn that option back off and they continue to be happy to talk until I reboot one of them... then back to not being able to see. I *think* multicast is enabled on my wifi and working correctly, but who can tell ;-)

[Harold Feit]

Is it permitted by your windows AND mac firewalls as well?

[rangerevo8]

Anyone can help? I had problem for my LAN-only sync setup. Maybe i misunderstood what it can do. I'm trying to create a 2 PC 1 Android sync where the 2 PC is at separate network (home and office) and i wan the folder to sync only with android when connected in LAN. (PC do not sync from home to office via internet)

 

I had a folder A shared on PC01, synced with Android01 at home-LAN. BitTorrent Sync on Android is set to not using mobile data. So it will Sync only when I connected to my home-LAN. It works fine until here.

 

Now I shared the folder A to PC02 at office-LAN (another network). At first, the approval wont appear on PC01 since I already disabled Relay, Trackers and DHT Options. So I turned it on for awhile and approved the PC02 into the sync. Then turn it back off. What I assume is Android01 was connected to office-LAN now and it should sync with PC02.

 

However, I found that PC01 is also uploading for PC02 together with my Android01. I do not want PC01 at home using internet's upload. I double checked both PC01 and PC02 had disabled Relay, Trackers and DHT Options. However, there is no options to disable in Android01. Do I need to do anything on Android01?

[colinabroad]

@rangerer_v08

_{I don't think this will work.  I have been trying to get a three way sync similar to this and as soon as you add the third peer (your office folder in this case) ALL peers try to sync together,  I don't think it is possible to have the two PC's ONLY syncing with the Android - unless you have two different sync's set up on the same android folder; one for each PC?}

@ Great Marko,

So are you saying switching the preference 'use lan broadast' in advanced settings (1.4.83) to false will INCREASE LAN trasnsfer speeds?  This seems counterintuitive to me as it appears that ALL methods of communication are now turned off? - , sorry, this should have been attached to your previous post,

[GreatMarko]

@ Great Marko,

So are you saying switching the preference 'use lan broadast' in advanced settings (1.4.83) to false will INCREASE LAN trasnsfer speeds?  This seems counterintuitive to me as it appears that ALL methods of communication are now turned off? - , sorry, this should have been attached to your previous post,

There isn't a "use lan broadcast" advanced setting, so I'm not sure I quite understand what you're referring to?

 

Anyone can help?

@rangerevo8, Sync by its very nature connects your devices in a "mesh" network arrangement, that is to say that all devices under normal circumstances will connect and share data with each other.

If you have 3 devices in your "mesh", let's call them A, B, and C, you can't configure Sync to just sync a folder between A and B and then that same folder to sync between just B and C separately without using A; all 3 devices using the same key (secret) on a folder can potentially share data and sync with each other - that's what a "mesh" network is.

[colinabroad]

Preferences/advanced/more options - 7th line down is 'folder_default.use_lan_ broadcast' with options true or false - in between the line for use DHT and use relay

 

Which switch for LAN are YOU referring to GM ? as I cannot find any other way in 1.4.83 to turn on or off the 'use LAN' feature ?  

I have managed to get a screen dump less than 500Kb so you can see for yourself - scratch that - it won't let me upload a simple word file and the pdf is 503Kb aarrgghh

[GreatMarko]

Preferences/advanced/more options - 7th line down is 'folder_default.use_lan_ broadcast' with options true or false - in between the line for use DHT and use relay

 

Which switch for LAN are YOU referring to GM ? as I cannot find any other way in 1.4.83 to turn on or off the 'use LAN' feature ?  

I have managed to get a screen dump less than 500Kb so you can see for yourself - scratch that - it won't let me upload a simple word file and the pdf is 503Kb aarrgghh

 

Ah, right ok - the advanced "folder_default.use_lan_broadcast" setting essentially maps to the per-folder "Search LAN" setting, however this particular advanced setting only applies to subsequently added new folders (as do all advanced settings prefixed with "folder_default.") and NOT to your existing folders.

 

The setting I was referring to in my post way back in July 2013 was the "Search LAN" option on each folder's own preferences dialog.

 

So, revisiting @colinabroad's question:

 

@ Great Marko,

So are you saying switching the preference 'use lan broadast' in advanced settings (1.4.83) to false will INCREASE LAN trasnsfer speeds? This seems counterintuitive to me as it appears that ALL methods of communication are now turned off? - , sorry, this should have been attached to your previous post,

Changing "folder_default.use_lan_broadcast" to "false" will have no affect on current LAN transfer speed, as this setting only applies to new folders you then add to Sync, and not existing ones.

Disabling each existing folder's "Search LAN" setting however may improve LAN transfer speed, as there will be less traffic on your network as a result of "Search LAN" being disabled.

[rangerevo8]

 

@rangerevo8, Sync by its very nature connects your devices in a "mesh" network arrangement, that is to say that all devices under normal circumstances will connect and share data with each other.

If you have 3 devices in your "mesh", let's call them A, B, and C, you can't configure Sync to just sync a folder between A and B and then that same folder to sync between just B and C separately without using A; all 3 devices using the same key (secret) on a folder can potentially share data and sync with each other - that's what a "mesh" network is.

 

Thanks. I understand that it have a mesh type of syncing. However, I think I misunderstood what the FAQ explained about not sync via the Internet as below.

 

Can I force Sync to do local network (LAN) syncing only and not sync via the Internet?

Yes - simply disable the Relay, Tracker, and DHT options (these are per-folder settings). Sync will then no longer connect to any remote devices (outside your local network).

 

So, disable these settings only prevent the approval from being discovered via Internet? Once approved, it will sync via Internet regardless of whether Relay, Tracker, and DHT options is enabled or disabled? Just to wanted to clarify how it works.

[GreatMarko]

So, disable these settings only prevent the approval from being discovered via Internet? Once approved, it will sync via Internet regardless of whether Relay, Tracker, and DHT options is enabled or disabled? Just to wanted to clarify how it works.

These settings relate to how your data syncs. However, you'd need internet access in order to be able to use/approve links. If you don't have/wish to do this, you'll need to share keys (secrets) rather than links.

[colinabroad]

Thanks GM, I had forgotten the per folder settings as they had disappeared off the left hand side of my window - something that is discussed in a different thread