Oslec Echo Cancellation

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Asterisk Users 4 Comments


Who should insert dahdi_echocan_oslec.ko module in Ubuntu 14.04?

dahdi start/stop service?

I have a test installation that is not launching it when asterisk/dahdi starts.




4 thoughts on - Oslec Echo Cancellation

  • dahdi_echocan_oslec should be built by default. What you may miss is the
    ‘echo.ko’ (OSLEC) kernel module.


    /sbin/modinfo echo

    Do you have it available?

    The https://notabug.org/tzafrir/dahdi-linux-extra repository is where I
    maintain a copy of DAHDI with OSLEC and from it I create the OSLEC patch for the DAHDI package in Debian.

  • Ooopss.

    I did not make myself clear.

    All modules are in place and working – *if* I “modprobe” them manually.

    The problem is “service dahdi start” does not load echo+dahdi_echocan_oslec.

    I have a production system that does it. I just do not know how.

    After copying this system to another machine and upgrade it (apt-get dist-upgrade), echo+dahdi_echocan_oslec does not get inserted anymore and I am wondering why.

    I intend to upgrade the production system tomorrow night and this “bug” is haunting me.



  • The echo canceller modules get loaded automatically when needed: if you have the line ‘echocanceller=foo,12’ in /etc/dahdi/system.conf and run dahdi_cfg, dahdi_cfg will attempt to configure the echo canceller ‘foo’
    for channel 12. The DAHDI core (kernel code) will notice it has no such echo canceller and try to load a module caller ‘dahdi_echocan_foo’.

    So, what do you have in /etc/dahdi/system.conf ? What is the output of lsdahdi?

  • I do have a bunch of lines like these:

    May the problem be that in this copy we do not have the cards installed?

    Quit odd choice dahdi_cfg made if this is the case, since “service dahdi start” installed the drivers for these same inexistent cards!

    Nothing since the cards are installed inside the production system.