Debug page

You can debug a GrapeCall by accessing the url “/call/debug” on your installation.


You must have super user rights to access this page.


A cleaner runs periodically and checks from GrapeCalls that have wrong finish status.

Self Test


The Self Test Page should be enabled on your installation.

The Self Test Page provides a way to quickly check for common issues that might make your Grape Call experience not so nice.

It can be accessed through the proper button on any Grape Call:

Grape Call Self Test

Then, a new tab will open and you will see some tests for the common issues. The page currently looks like:

Grape Call Self Test

Those are the tests currently performed:

Grape specific tests

  • Browser support:

    • Checks if the browser is supported


  • Audio capture

    • Checks the microphone is able to produce 2 seconds of non-silent audio

    • Computes peak level and maximum RMS

    • Clip detection

    • Mono mic detection


  • Check WxH resolution

    • Checks the camera is able to capture at the requested resolution for 5 seconds

    • Checks if the frames are frozen or muted/black

    • Detects how long to start encode frames

    • Reports encode time and average framerate

  • Check supported resolutions

    • Lists resolutions that appear to be supported



    • Verifies it can talk with a turn server with the given protocol

  • IPv6 connectivity

    • Verifies it can gather at least one IPv6 candidate


  • Relay

    • Verifies connections can be established between peers through a TURN server

  • Reflexive

    • Verifies connections can be established between peers through NAT

  • Host

    • Verifies connections can be established between peers with the same IP address


  • Data throughput

    • Establishes a loopback call and tests data channels throughput on the link

  • Video bandwidth

    • Establishes a loopback call and tests video performance on the link

    • Measures rtt on media channels

    • Measures bandwidth estimation performance (rampup time, max, average)


By default calls between 2 participants are done peer-to-peer. This means the connection is directly between the clients and ignoring the Videobridge (Grapecall server).

In some environments, especially when all users are using a VPN, this can lead to unforeseeable connection issues.

In order to turn peer-to-peer off follow these steps:

  1. Add a new config file on your grapecall server:


  1. Put this into the file:

config.p2p.enabled = false;

  1. restart the web container:

docker restart grapecall_web_1