[Asterisk-Users] Cisco Callmanager & Asterisk for Voicemail revisited

[Rich Adamson]

> Some of you may remember back in May the thread on using Asterisk as a
> voicemail server for a Cisco Callmanager system.
> 
> My own Callmanager system is integrated into an Asterisk server for
> voicemail (and other things). Back in May I was using H323 for
> integration, but since I've upgraded to CCM 4.1 I have switched over
> to SIP.
> 
> The integration with H323 required using Call forwarding to send the
> call to an extension on Asterisk. For example, extension 7443 would
> forward to 27443 on Asterisk which looked something like:
> exten => _27XXX,1,Voicemail(u${EXTEN:1})
> 
> Obviously setting this for each and every phone on Callmanager was not
> an option for any wide deployments, and Paul Davidson investigated
> some of the other options. Paul discovered that it was possible to
> setup a voicemail pilot, tick the voicemail box, etc. but you would
> lose the ability to have the caller ID information added to the
> voicemail.
> 
> This wasn't an option for us, as caller ID is quite important.
> 
> Up until now, I have continued with the custom extension option,
> setting up the appropriate call forwarding when new phones were added
> to the system. The trunk between CCM and Asterisk changed to SIP after
> the CCM upgrade, but everything else stayed the same until I revisited
> this today.
> 
> To summarise what I have accomplished:
> 
> Full voicemail integration between CCM and Asterisk with the following features:
> - MWI
> - Voicemail on the CCM side is enabled by selecting Forward to
> 'Voicemail' rather than yucky custom extensions. Allows for wide
> deployment.
> - Messages are accessed by pressing the 'Messages' button on the CCM
> phones, or dialing the VM pilot number.
> - If a CCM user doesn't want to take a call, they can press the
> iDivert softkey to send to voicemail immediately.
> - CCM users can forward all calls to voicemail in the ccmuser pages,
> or by pressing CFwdAll and entering the pilot number or messages.
> - All the standard Asterisk voicemail features work just fine, eg: vm to email.
> - more
> 
> Bugs with the setup:
> - If there's a SIP device registered with the Asterisk machine
> handling the voicemail, and the call path is something like: Sip
> Device -> Asterisk -> CCM. If the call subsequently reaches voicemail,
> Asterisk prompts for proxy authentication and CCM drops the call. This
> problem can be avoided by using usernames that don't match the caller
> id, eg: [sip7345], or having a machine dedicated to Voicemail.
> - That's all I've found
> 
> These options have been tested with Asterisk 1.0.8 and CCM 4.1(2)sr1.
> If this is something that people would be interested (and you made it
> this far), I'd be quite happy to whip up some instructions and add it
> to the wiki.

I recall several posts asking for this type of config over the last
year or so. Placing it on the wiki would be excellent. Make sure you
note the ccm version requirements (and why), etc, as someone is bound 
to say something like 'I have ccm v3.x and I can't make it work'.