BitTorrent Sync

[eureka]

BitTorrent put Sync in pre-Alpha Sync in public access. It has Linux ARM client that works on Kindle (as tested on Kindle Touch).

Looking ahead, it could turn into niche solution for syncing Kindle and main computer. Maybe not for all people, but for some.

I've achieved successful syncronization between my computer and Kindle Touch 5.3.2 with Sync v1.0.75. Fact of file creating/deleting is propagated in 5-20 seconds. Here are used configuration files:

• Kindle:
  Spoiler:

  {
    "device_name": "Kindle",
    "listening_port" : 12321,
    "check_for_updates" : false,
    "use_upnp" : false,
    "download_limit" : 0,
    "upload_limit" : 0,
    "shared_folders" :
    [
      {
        "secret" : "X",
        "dir" : "/mnt/us/documents/bridge",
        "use_relay_server" : true,
        "use_dht" : true,
        "search_lan" : false,
        "use_sync_trash" : false
      }
    ]
  }

• computer:
  Spoiler:

  {
    "device_name": "Host",
    "listening_port" : 12322,
    "check_for_updates" : false,
    "use_upnp" : false,
    "download_limit" : 0,
    "upload_limit" : 0,
    "shared_folders" :
    [
      {
        "secret" : "X",
        "dir" : "/home/user/kindle",
        "use_relay_server" : true,
        "use_dht" : true,
        "search_lan" : false,
        "use_sync_trash" : false
      }
    ]
  }

Sync has much more configurable configuration settings (for example, web interface credentials), you can look at them with option

--dump-sample-config

Other command-line options could be viewed with Sync --help .

Sync puts its settings and log in .sync folder along the executable, but it could be changed in configuration file.

Sync can "stuck" on Kindle at the first start just after launch because of low available entropy. You can add available entropy by typing anything on Kindle [virtual] keyboard or by constant swiping over the touchscreen. But anyway, after 3-4 minutes Sync will "continue to work" even without producing the entropy. It needs 640 bits of entropy at first start and if it will be provided with them it will not "stuck". Number of available entropy bits could be displayed with:

cat /proc/sys/kernel/random/entropy_avail

To access Sync web interface (if it's not disabled) you can forward its port with SSH:

ssh -L8889:localhost:8888 root@192.168.15.244

Then access web-interface on localhost:8889 on main computer.

Nothing should be changed in iptables chains. By default, Kindle Touch has policy ACCEPT for OUTPUT chain and rules for ACCEPT tcp with state RELATE/ESTABLISHED and ACCEPT udp with state ESTABLISHED in INPUT chain. It's sufficient for Sync.

[twobob]

your information is good for all devices I believe. Thanks for this.

[eureka]

I've read an anecdotal report about very slow (practically, non-working) sync between just two devices (adding more devices fixed it), so it's possible I've had perfect setup, but current Sync quirks ruined my experience.

[kos13]

I am involved in development of Sync, so want to clarify few things:

1. We never tested it on Kindle, so hadn't had any chance to optimize for the device. It is nice that it works
2. Sync uses AES256 to encrypt the traffic, we saw some reports that this could significantly slow down the synchronization.
3. It is in pre-Alpha, so there should be issues that we hadn't found yet.

If we might get a help from you - debug log files - to analyze the issue, then I am sure it will work perfectly on Kindle.

Anyway we will touch Kindle at some point of time, but log files could significantly speed the things up.

Thank you testing Sync,
kos

[twobob]

Damn good of you.

[geekmaster]

The newer Kindles have AES hardware in the SoC, which could improve speed and battery consumption.

[eureka]

I've updated first port with impressions of new build v1.0.75 (thanks to kos13). In short, it works fine, but first start could be noticably slow because of high amount of required entropy. I was also wrong about required changes of iptables rules.

[knc1]

Originally Posted by eureka

Nothing should be changed in iptables chains. By default, Kindle Touch has policy ACCEPT for OUTPUT chain and rules for ACCEPT tcp with state RELATE/ESTABLISHED and ACCEPT udp with state ESTABLISHED in INPUT chain. It's sufficient for Sync.

Did you use my new KUAL Firewall Report button to learn that?

[eureka]

Originally Posted by knc1

Did you use my new KUAL Firewall Report button to learn that?

Is it new brand for good ol' iptables -L -v ?

[knc1]

Originally Posted by eureka

Is it new brand for good ol' iptables -L -v ?

one touch instead of all that typing.
SUPER PLUS - adds: -n so you don't have to wait for DNS lookups.

[eureka]

Sync is available to all interested now.

[farfeduc]

Could you detail how you installed it?

I'm a newbie but I'd like to test it on my PW.

Thx already for info and keep up the good work !