Sync Problems Between Two Locations

[jerue]

Hi everybody,

 

following senario:

 

All devices are QNAP-212P (BitTorrent Sync Version 1.1.82)

 

Two sites connected via VPN only routed without firewall in between.

All of them have the same secret-key and the same shared folder.

 

In Site A, each device finds the other. Once there is a device in location B, it can be seen none of the site A. All devices in A can´t see the device in B.

 

Am I doing something wrong? Is there a problem with Sync?

 

Thanks

Jerue

 

[RomanZ]

jerue,

 

How both sites are connected to the internet? How IPs are set up in both sites - are they same subnet or different subnets?

[jerue]

 

The two are connected via Backbone-VPN. They are in two different subnets but they allready routed. All QNAP´s get an ip from dhcp-server.

 

From location A, I can access the web interface on the Cient from Site B without problems.

Edited March 27, 2014 by jerue

[RomanZ]

jerue,

 

You have rather complex setup. As a quick test I suggest trying to set predefined hosts on each of QNAPs to point one to another.

 

If you want to understand fully what is happening, you'll need to debug it a little bit. Let me describe how BTSync works:

 

Every peer contacts the tracker, t.usyncapp.com over UDP port 3000 and let tracker know the share ID, peer IP:port in the LAN and peer's external IP:port. The tracker in response shares the same info about other peers it knows with the same share ID. Then peer tries to contact other peers on both local and external IP:port. In your case it means that it fails both ways.

Strange thing here is that if direct connection fails, both peers will try to connect via relay server - which is not happening in your case.

I consider checking your firewall settings as well.

[jerue]

RomanZ,

 

thanks for the quick support!

I'll be the firewall settings check again. I will assign each host predefined hosts.

 

After that I will give a feedback.

 

regards jerue

[jerue]

RomanZ,

 

I have since prepared a little time. Here is a sketch of the network.

 

I've added all BitTorrentSync clients on the QNAP's other clients as predefined hosts.

The sync devices only use the local network. (But I have already tried to manage the devices via the Tracking Server.)

One question I have, all sync devices should use the same port or all devices use a different port? I have already tried both options.

QNAP-TBSync.pdf

[RomanZ]

jerue,

 

Thanks for the picture. I hope that the box staying next to the city icon is not a NAT, but VPN tunnel? I consider checking that your VPN tunnel has MTU at least 1500, otherwise you can have connectivity issues even with predefined hosts.

[jerue]

No NAT and the MTU is allready 1500.

How can i affect replication traffic ?

IIRC BTSync should be able to work even without internet connection, correct ?

So it should be able to sync between routed subnets (or do i need to have a tracker server for the routed segments to see each other) ? Therefore the predefined hosts setting should be useful, right ?

Does the predefined hosts setting (on the server) affect client connection behaviour (of clients not added to the hosts list) ?

[RomanZ]

IIRC BTSync should be able to work even without internet connection, correct ?

Right. 

 

So it should be able to sync between routed subnets (or do i need to have a tracker server for the routed segments to see each other) ?

You can sync between routed subnets. Tracker is not necessary if you predefine hosts and ports.

 

Does the predefined hosts setting (on the server) affect client connection behaviour (of clients not added to the hosts list) ?

I'm missing your question. I would advise add a list of pre-defined hosts to all 5 your NASes. One in Area B should know of 4 existing NASes in Area A, while every NAS in Area A should have pre-defined host of NAS in Area B.

 

If you have predefined hosts already and peers from A still can't see peer from B - it means there is some connectivity issue between 2 sites over UDP protocol.

 

BTW, I see that the clients you use are rather old. There were plenty of fixes since that time. One of things worth to try is 1.3 client, which has ability to connect over TCP in different networks (just in case if there is some issue with passing UDP thru VPN gateway).