Call Fwd Unregistered vs. AAR

[zebranutz80]

I have a centralized telephony environment with CUCM8.6 running at our HQ.  We have a dozen branch sites that connect via MetroE back to HQ for call handling.  The Branch sites use SRST in the event of a WAN outage.  Each branch site has a few PSTN lines connected to FXO ports on a 2921 router. 

In the event of a WAN outage at a branch site, I'd like to keep calls flowing from HQ to the branch site.  Rerouting calls to the PSTN is the obvious answer.  I'm looking for a suggestion as to how to best accomplish that. 

I've tested Call Fwd Unregistered(CFU) to a PSTN line at the branch site.  This worked perfectly.  However, I don't want to have to change every extension's CFU setting.  I'm looking for a global setting that will forward a particular sites calls to a PSTN number in the event of a WAN outage.

Is AAR the answer?  I've read that CUCM can not detect an outage and AAR would not apply.  I understood my readings to say that AAR only works when there is not enough available bandwidth.  As a WAN outage =  zero bandwidth, I would think AAR should apply in this situation.

Does anyone have any suggestions to my scenerio?  What have you seen work best?

Thanks for your help!

-tom

[Chris Deren]

Tom,

Forward on unregistered is your solution. AAR kicks in only when Call Admission Control invokes it after designated bandwidth to the location has been exhausted.

So, these are 2 comptely different features sets which are commonly confused.

HTH,

Chris

[zebranutz80]

Thank you Chris.  That confirms what I thought. 

Now that I know that CFU is the answer, I'm looking for a way to not have to change 75 extensions.  I can use BAT, but wanted to ask if there was a better way.  Perhaps a setting on the gateway or device pool config???

[Leo Salcie Tejeda]

Hi Zebra,

The easiest way is use Bulk administration tool.

Regards

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