CME 4.2 and Exchange 2010 UM

[jpodplesky]

I have a client that has CME 4.2 and wants to use Exchange 2010 Unified Messaging. On my development network I setup a duplicate environment with CME 4.2 on a 3725 router. The problem I am having is Exchange is reporting it has rejected the call because there is no UM IP Gateway. Here is how it it is setup

On the 3725 FA0/0 is on the native vlan of 172.16.1.3, CME is on a subinterface of 172.17.99.1 The vlans are setup on a 4006 and the vlans can ping eachother. I have the following dial peer 

dial-peer voice 8000 voip

destination-pattern 8...

session protocol sipv2

session target 172.16.26.x (address of the exchange server)

session transport tcp

On the exchange server I have a UM dialplan, a pilot number of 8000, A UM IP Gateway with the address of the subinterface 172.17.99.1. I have also tried a UM IP Gateway using the address of (FA0/0 172.16.1.3)

When I dial the pilot number, I get a busy. In the event log of the exchange server I get the message

The Unified Messaging server rejected an incoming call with the ID ...... @ (172.16.1.3) Reason: No valid UM IP gateway was found with address 172.16.1.3 (FA0/0 address)

Any Ideas?

[Jonathan Schulenberg]

You need to bind the SIP process to the appropriate interface. Without these commands the SIP dialog will use whatever address is assigned to the interface the packet arrived on.

voice service voip

sip

  bind control source-interface Loopback0

  bind media source-interface Loopback0

Note: It's recommended that you bind everything - including CME - to a loopback, not a physical interface. For the purposes of your lab this should get the SIP dialog going though.

[jpodplesky]

Jonathan, Thanks for the quick response. If you don't mind I have a question. In creating the loopback, it will need to be on a different subnet than fa0/0.99, which would mean I would need to change the ip source-address in the telephony config, correct? what else would I need to change? I am in no way a CME expert (why I have a development lan)

[Jonathan Schulenberg · Accepted solution]

You would also need to update the DHCP option 150 address. If you have ACLs on the router for toll fraud prevention that control H.323, SIP, or TFTP access be sure to update those as well.

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