If I have a phone with three DNs asociated with it on different lines. If I receive a voicemail in Unity for the DN associated with Line 3 on the phone should I expect to see the MWI lamp turn on the phone. Right now we have a scenario where this is not happening, when I look in Unity I see that the Indicator Lamp is on but the lamp is not lit on the phone. To be honest, I am not sure if this is expected behavior or not and could not find any Cisco documentation to clarify.
It depends. Check the configuration page in CUCM for the DN. Under "Line Settings for this Device - Changes affect only this device", check the Message Waiting Lamp Policy. If you want the flashing envelope on the DN and the red light on the phone, set it to Light and Prompt.
That is the expected behavior as the MWI lamp only lights up for the primary extension. The other extensions should still have a little envelope status indicating a message.
You may be able to fiddle in Unity to use alternate extensions to light the primary extension's lamp when messages get left on the other lines. Just thinking aloud.
