Offline Buffer

steviehsa year ago

I want to use traccar to track my sailing boat, which is away from any wlan just for some time...
Are there any restrictions regarding the offline buffer:

  • size restriction (besides from memory/flash)
  • lost buffer if traccar client stops

As an alternative I could imagine to go with some 4G connection, but even then you are away from any network from time to time :-)

Anton Tananaeva year ago

The buffer is stored on disk, so it won't be lost if the app is killed. There is no restriction in the app, so it can store as much as the OS allows it to.

steviehsa year ago

Great! Thanks!

Shawn6 months ago

EDIT: leaving the long post for anyone else who lands here.
TLDR: long delay in getting buffered data to post to server. Thought it was broke, or lost. It's only a couple hours of driving, buffer size likely less than 1MB, yet is over 24 hours before it shows up on the server. Any tips for getting it to post sooner?
I did move my server (to new DMZ VLAN network, so I could reach it over VPN from the road), but only after failing to get buffered data posted after many hours.

Looking to do the same. That is, not be reliant on cellular, in case I go where there is no coverage; want to forgo an other data-service-plan; and/or because I'm not crazy about sending my location data unencrypted over public networks.
(I do understand https is a tall order for a Freematics device)

My primary use is to track mileage to claim the business expense. No need for real-time tracking.

I've been playing with this, but not getting offline buffering to work.
EDIT: works: I eventually received extremely detailed track log records on the server, after about a 24 hour delay.

My setup and path taken, so maybe I (others) can learn why I had such a long delay:
I've installed a server instance on my local network.
I've installed the Android Traccar Client. My plan is to use Freematics, but want to see it work before making that purchase.
My first test, I have Traccar Client on a Pixel 3 (old phone, no SIM card). Default settings + my custom server + enable offline buffer. Register the device, confirm location reported.
I spend a day visiting clients, leaving the Pixel 3 in the car, traccar service running.
End of the day, I return home, connect Pixel 3 to WiFi to let it post buffered data to server.
I'm excited to see it posted several stops, but, my tracks are straight lines, so I edit the settings from default.
Default distance = 0 : unclear what that means: Also unclear on the combination of settings: distance, frequency, angle. I would assume if any condition is met, create a new record. So, as long two of the three are small values, I should get a detailed track recorded.
Since my last trip was a fail, I set it them to 150 M, 300 Seconds, 4 Degrees. It would be helpful if the app showed UNITS for these settings. I had to look them up.
With updated settings, I let it track me to a Halloween party and back. But when I check the server the next morning, nothing. Not even a few stops with straight lines. That's when I decided to make the server reachable over VPN, I added Traccar Client to my current phone (Pixel 6). Registered the new device. Installed OpenVPN, configured VPN, tested that the Pixel 6 device shows up as Online over cellular connection + VPN.
This could work, but if I buy a Freematics, then even more complicated: Pixel 6 with VPN + Hotspot + Proxy Server to let the Freematics post in real-time securely.
I really want to know that Offline Buffer works. From Android Client first, but also from Freematics.
And I'm hoping that both devices, will automatically reconnect to WiFi when in range, find that they can now reach the server, post each record from buffer to server, and after receiving acknowledgment from the server, remove record from buffer.
Can someone help me understand why the long delay?
Thanks

Anton Tananaev6 months ago

Have you checked server logs to see what was the upload pattern?

Shawn6 months ago

I have now. Wow, very verbose. I will record some more tracks and then pay attention to the logs. Thanks.

Shawn6 months ago

Update: I didn't end up going anywhere, but did work on reducing volume of needless data.
In an attempt to silence reporting when stationary, but retain reasonably accurate tracks, I set:
Angle 5
Distance 200
Frequency 1200
Ended up getting near constant updates due to location jitter and wildly changing Angle.
Fixed: eliminated the jitter by reducing Location Accuracy from High to Medium.
An hour later, I leave the traccar client service running, but turn off WiFi (no SIM card, so connection severed).
An couple more hours later, I turn WiFi back on. That was 2.5 hours ago, and I still have no new server log entries.
So question remains: What needs to happen to cause the client to begin submitting data after WiFi connection is restored?

Anton Tananaev6 months ago

Have you checked the client troubleshooting guide? Make sure you read the documentation before asking questions.

Shawn6 months ago

nevermind :( device had more than one SSID set to autoconnect and was on the wrong network. Tis working now.

SJ23 days ago

Hi, I have the same problem. I have 2 device, one is gps tracker from JIMIIOT and one is the mobile device. On traccar server, it does not show the offline buffers. Anyway for me to configure the server to process the offline buffer?