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New Member


Hi Peers,

just wanting to ask your thoughts on config of AAR.

We have our region and locations available, but wanted to know:

Once the AAR group is created, is assigning the AAR group only though each DN? (meaning BAT tool to apply to all?) or is there somewhere which i haven't seen to add to a Partition etc.

Secondly can you confirm AAR will not work if the WAN link goes down? And thats when Route Lists come in?

Much appreciated

  • IP Telephony


Yes, AAR groups are applied to gateways, voicemail ports and DNs. You need to make sure that the phones have their external phone number masks properly set and the AAR group definitions have the proper prefix (9, 91 etc) set.

AAR doesnt work when wan goes down, although with CCM 4.2 and forward (not in 5.0) you can Forward on not register option to divert calls through the PSTN

New Member


Thanks Shanky!

We have CCM5, so i supposed to auto route calls via PSTN when the WAN is down is through Route Groups. Would you agree?

THanks again

Hall of Fame Super Silver


That's incorrect, AAR only kicks in when the Location bandwidth has been exhausted. CCM 5.X has not intruduced any new workaround for WAN outage. In fact CCM 4.2 has a new feature "call forward on unregistered" where you can re-route calls when a phone unregisters with CCM, such as in case WAN outage.

Route List/Group will not achive your desired outcome, when WAN goes down, phones unregister, and when you dial the phone's DN it will always be best match, before CCM will start looking at route patterns, hence the new feature in 4.2.


New Member


cderen, thanks for that

and you are correct it wouldn't. I apologise as i have not painted the desired picture for you.

We have 1 cluster with a remote branch site connecting to CCM via WAN .

If the WAN is down, SRST (which we have configured) will kick in for the Branch office and route to PSTN. From HQ however, if AAR is not effective in this situation, is it correct in saying the Route list/Route Groups are responsible for this?

Hall of Fame Super Silver


No, you will need to dial the full phone number, the 4 digit or whatever your dialplan is will not work, unless you have CCM 4.2 or 6.0 (coming out soon) where you can do call forwarding on unregistered, which would be set to the full phone number. It will simply go to VM or whatever you have set for call forward busy/no answer.

HTH, please rate all useful posts!


New Member


Hi Guys.. Just finally on this topic. I have done as much as the following and not sure if i have done this correctly

(as you know we have WAN between HQ and the Branch site. Branch site relies on the CCM in HQ, but has SRST if loses connection)

In order to seamlessly route to PSTN

At HQ:

I've set a test phone in HQ to AAR 1 group

I've set the test phone to be in the AAR_CSS1

I've set the gateway in HQ to AAR 1 group


I've set a test phone in Branch to AAR 2 group

I've set the test phone to be in the AAR_CSS2

I've set the gateway in HQ to AAR 2 group

AAR group prefix have been set as: 0 for outside line (australia) and the remaining area code to complete the 10 digits?

eg.. prefix: 0088901

will this work? We use 4 digit dialling so i assumed adding the prefix of auth code plus area code.

Is the above efficient to get successful AAR?

If you can help me... Your a champ!