Subscribe a BLF button to Monitor a Voicemail Box

I am going to try and start a weekly Saturday morning technical blog about some cool Tip or Trick you can do with FreePBX that most people are not aware of. As anyone who knows me over the years spelling and grammar are not by strong suite so please do not take offense if you find mistakes. I am here to try and provide valuable technical information.

If you have any request for things you would like me to go more indepth on please feel free to comment here and I will see if I can cover it for you in a future blog.

In this first series I am going to show you how you can setup a BLF button to monitor a voicemail box of any user on your FreePBX system. In the past this feature was not possible as Asterisk has no native ability to let a BLF button subscibe to a voicemail box and display when their are 1 or more waiting new voicemails. If you are using FreePBX 2.11 and the FreePBX Distro this feature is now possible.

A asterisk custom dev state hint for each voicemail box will now be auto created. If you log into the Asterisk CLI and issue the following command you will see the hint for each voicemail box called xxx@dialvm

core show hints

In our example above voicemail box 101 has a hint created that you can program any BLF button to as *98101. Now anytime voicemail box 101 has one or more new messages waiting the BLF light will be activated on your phone. Pressing the BLF button will prompt you to login with the password for voicemail box 101.


Now you can finally setup that general voicemail box and add a button to any phone that needs to be notified when a new voicemail is left. Thats all thats to it. Hope you find this feature useful.

Also remember to review our new wiki for more indepth information on FreePBX and all things related to the FreePBX Product.

The related wiki post on this feature can be found here.

Nice, thanks for posting this Tony. I love the idea of periodic tips-and-tricks posts; with a system as complex as freepbx, it’s pretty much a guarantee there are capabilities I’d find useful that I just haven’t discovered or thought of yet. Keep them coming!

This is a great tip, but does not appear to work on the version (PBXiaf) I use with my FreePBX 2.12 install. Is there any way to add the code to FreePBX 2.12 without reinstalling the whole FreePBX distro?

This information, and all the other information about how to use Feature Codes, should be included at the bottom of the screen when you select the Feature Codes module.

I am using Digium Phones with the DPMA addon. I can’t seem to get the BLF to work. If i press the key that is assigned to dial *98299, 299 being the voicemail extension I’m trying to monitor.
I’m thinking it is the Subscription URL string that I am trying to use is incorrect. Anyone able to help me as to what the Subscription URL string would be to enable the BLF to indicate the presence of voicemail in this extension. I have run the core show hints command and all is well in the output.

I have several people who want to use this, but the BLF lamp stays lit even though there are no new VM’s. It seems to be responding to files in the “Old” folder.

Surely I’m doing something wrong! But it’s just programming *98XXXX in a BLF button…Right?