Unable to open DAHDI pseudo device error in asterisk vicidial servers

    In this article we are going to learn how to solve the issue "Unable to open DAHDI pseudo device error" while installing DAHDI in asterisk or vicidial dialers or FREEPBX. you may also notice the error "Unable to open master device '/dev/dahdi/ctl'". This article will help you to solve this DAHDI pseudo device error issue.

"ERROR: WARNING[10762]: app_meetme.c:829 build_conf: Unable to open DAHDI pseudo device"

unable to open dahdi pseudo device

What is DAHDI?

    Digium Asterisk Hardware Device Interface (DAHDI) 

    DAHDI is a collection of open source drivers, for linux, that are used to interface with a variety of telephony related hardware. 

It consists of two parts.
The DAHDI-Linux project contains the individual board drivers for the supported hardware. 
The DAHDI-Tools project contains an assortment of user space utilities that are used to setup and test the drivers.

Why the DAHDI Pseudo error Arises?

    In vicidial based dialers, MeetMe asterisk Application is used for there agent conference functionality, For MeetMe application to work properly the DAHDI kernel modules and a functional DAHDI timing source must be present for conferencing to operate properly, If the DAHDI module is missing or not functioning properly you will see the below error in the asterisk console ,which leads to Vicidial Time synchronizations error and your session has been disabled issue.
ERROR: WARNING[10762]: app_meetme.c:829 build_conf: Unable to open DAHDI pseudo device

Solution to solve DAHDI Pseudo error

    Make sure the DAHDI driver is installed properly and running as a service.
For vicidial based dialers if you are not using any Digium telephony cards then proceed with the below commands to make sure the dahdi is installed properly
dahdi_cfg -v
Make sure the above command displays output as shown below, which means workign fine.
DADHI Tools Version - 2.4.1
DAHDI Version: 2.4.1
Channle map:

0 channels to configure.

if the above command displays below error, proceed with the solutions provided in this article

DAHDI Tool Version - 2.4.1
Unable to open master device '/dev/dahdi/ctl'
1 error(s) detected

Option 1: Modprobe dahdi

       Install the Dahdi module manually by running the below command

modprobe dahdi
asterisk -vvvvr
module unload chan_dahdi.so
module load chan_dahdi.so

note if you are using any digium/sangoma telephony cards then follow my blog article - How to configure digium cards and how to configure sangoma cards.

Followed to the above commands, check the dahdi driver installed and working fine by running below commands

; make sure error in output
; make sure you get 99.9% or 100%

Option 2: Reinstall DAHDI

    If you feel DAHDI software is not installed properly or damaged, remove the existing DAHDI driver and install the latest or same version, Check out my article on Removing and reinstalling DAHDI driver


    Hope this article is helpful in solving the issue DAHDI Pseudo device error in vicidial or freepbx ,also you learnt how configure digium cards and reinstall the dahdi. For professional support reach me on skype or telegram id: striker24x7