CME & H.323

[jondudding]

Hi all,

We have a CME 4.0.3 running as a gateway to a Nortel 61c PBX gatekeeper. All calls are setup to be routed over the H.323 trunk (see config below).

During a call I can see the trunk coming up in the 'debug h323 h225 asn1' but all I get is ringback. The remote set does not ring.

The weird thing is that calls made from the central PBX are getting routed correctly to the remote CME and I the call connects successfully.

We are desperately trying to get this up and running by Monday morning. Any help is appreciated!

Thanks in advance,

Jon

==================================

!

voice service voip

allow-connections h323 to h323

allow-connections h323 to sip

no supplementary-service h450.2

no supplementary-service h450.3

supplementary-service h450.12

h323

h245 tunnel disable

h245 caps mode restricted

!

!

!

voice class codec 1

codec preference 1 g711ulaw

!

interface Serial0/2/0:0

ip address 192.168.134.2 255.255.255.0

h323-gateway voip interface

h323-gateway voip id SS_1 ipaddr 192.168.38.2 1719

h323-gateway voip h323-id cisco

h323-gateway voip tech-prefix 1#

h323-gateway voip bind srcaddr 192.168.134.2

!

dial-peer voice 10 voip

destination-pattern .T

session target ipv4:192.168.38.2

dtmf-relay h245-alphanumeric

no vad

!

telephony-service

load 7941 TERM41.7-0-3-0S

max-ephones 48

max-dn 96

ip source-address 199.xxx.34.1 port 2000

calling-number initiator

service phone videoCapability 1

system message LFC

url services http://10.1.10.1/voiceview/common/login.do

url authentication http://10.1.10.1/voiceview/authentication/authenticate.do

time-zone 12

voicemail 600

max-conferences 8 gain -6

call-forward pattern .T

call-forward system redirecting-expanded

moh music-on-hold.au

web admin system name

dn-webedit

time-webedit

transfer-system full-consult dss

transfer-pattern 9.T

create cnf-files version-stamp 7960 Oct 31 2006 17:41:35

[dgahm]

Have you tried session target ras in your VOIP peer? ipv4: is used to connect directly to another H323 endpoint. In your case you want the gatekeeper to handle the call.

Please rate helpful posts.

[jondudding]

yes, we tried that. the calls don't match the dial-peer when I use 'session target ras' and get routed over the backup POTS circuit. Using the ipv4: target is the only one that allows the calls to get routed over the right dial-peer.

[dgahm]

That would suggest that the gatekeeper does not know how to route the call to the Nortel gateway. Do you need to send a tech prefix, or has the gateway registered a range of numbers with the gatekeeper?

Or it may be that the call is being refused because it is G729. You need a voice-class codec 1 under your VOIP peer in order for it to use G711. The default is G729. You could also use codec G711u, but I saw that you have the class defined already.

[jondudding]

there is 'tech-prefix #1' in the config.

I am suspecting that the RAS setup is not happening correctly between CME and the PBX which would explain why the 'session target ras' would not work. Ah! I just realized that the 'gateway' global command is not in the config. That would prevent the gw from registering with the gk and explains why the RAS target doesn't work.

We did try g711u earlier but then again, the 'gateway' command wasn't entered.

[dgahm · Accepted solution]

The router gateway is registering the tech prefix #1. The Nortel side also needs to register either a tech prefix or range of numbers with the GK.

If the router wasn't registered you wouldn't be getting inbound calls OK to the CME side.

Debug RAS would be interesting.

Are all calls routing to the PBX or just a range of extensions? At least for testing purposes, it would be good to try a more specific destination pattern like 4... just to get away from the T interdigit timeout. It should be OK, but I have seen issues with that.

[jondudding]

I agree...I will run 'debug ras' and 'debug cch323 ras' in the morning.

And, a range of numbers have been setup on the Nortel side for the CME site.

I'll post the debug tomorrow. Thanks.

Jon

[jondudding]

It is working now. The debug output showed that registration with the gatekeeper was being rejected. I double checked the gateway endpoint config for the CME router in the Nortel NRS application and the endpoint was defined as 'non-RAS H323'. I changed it to RAS H323, entered the 'gateway' command on the router and the registration occurred without any issues. Calls began flowing over the dial-peer whose session target was RAS.

After rebooting the 2821 (for another issue) registration was getting rejected again. I removed all h323-related commands, re-entered them and the trunk came up again. No issues for several days now. Thanks for your help.

Jon