Getting MWI on Polycom Phones to work with Asterisk

MWI is a feature that will flash the LED, and display an icon on the phone display when there’s a voicemail message waiting.

On the Asterisk side of things, there’s nothing special that needs to be done. Just make sure the mailbox parameter is set right in the phone’s sip.conf entry.

You may have to add @context to the mailbox entry. This seems to fix things for many users. Note that this context is the context specified in voicemail.conf for the extension, not the context specified in sip.conf

Before you start editing config files on the Polycom side of things, you should read the Soundpoint IP SIP Admin Guide, or at least familiarize yourself with the per-phone config file, as covered in section 4.6.3.

Section 4.6.3.5 of the Guide covers the Messaging functions, and 4.6.3.5.1 covers the <mwi/> tag, which is what you need to edit.

Here’s an example (change from the defaults in your firmware rev):

sip.cfg:
up.oneTouchVoiceMail=”1″

phone1.cfg:
<msg msg.bypassInstantMessage=”1″>
<mwi msg.mwi.1.subscribe=”” msg.mwi.1.callBackMode=”contact” msg.mwi.1.callBack=”8500″/>
</msg>

Replace 8500 with your VM extension.

You may have to set reg.1.displayName=”username”, which is an attribute of phone1/reg (for each line used) in your phonexxxx.cfg file to get the MWI to light. Setting bypassInstantMessage=”1″ doesn’t affect the light, it changes the message key behavior to go directly to voicemail instead of giving you a choice.

That should do it!

Now that you’ve got MWI setup, you may find yourself annoyed by the periodic tone that the phone will play when a message is waiting, even in DND mode! See these notes about Polycom SoundPoint IP MWI audio if you want to disable it.

One other note: If you have a multiline phone with newer SIP software (2.2.0) and want your Messages button to call into a generic Voice Mail extension, yet want your MWI’s to show up for a few different lines, you have to set your user_preferences and set the mwiVisible=”1″ this allows for MWI’s on lines defined in the MWI section that their callBackMode=”disabled”

<user_preferences
up.oneTouchVoiceMail=”1″
up.welcomeSoundOnWarmBootEnabled=”1″
up.backlight.onIntensity=”2″
up.backlight.idleIntensity=”0″
up.mwiVisible=”1″
/>