Loopback E1 - Dial Peers

[kartik.bhatia]

I am kinda embarrassed to ask such a basic question.

I have set up a lab with a back to back E1 from E1 0/2/0 to 0/1/0 – on the same router.

2 IP Phones. Ph1 DN – 1500. Ph2 DN - 07531 888 888

Route Pattern 9.xxxxxxxxxxx in CM pointing to this H323 GW.

Both E1 ports up – Multiple_Frames_Established

I want to call 9.07531888888 from Ph1 – go out an E1 port and come in the other, session target it to the CM and ring Ph2 DN.

I see the call come in to the GW, sh debug isdn q931 shows Number Unobtainable as the Disconnect cause code.

Out Dial Peer:

dial-peer voice 1 pots

dest-pattern 9.T

port 0/2/0:15

forward-digits 11

Inbound one:

dial-peer voice 2 voip

dest-pattern 9.T

session target ipv4:10.10.10.10

dial-peer voice 3 pots

incoming called-number

direct-inward-dial

What am I missing please?

Assist.

Thanks & Regards,

Kartik

[kartik.bhatia]

Assist Please.

[linuxchild]

Hello

does your cable between port 1 and 2  rspect the following schema

http://elhallak.wordpress.com/2011/02/24/how-to-make-corssed-e1t1-cable/

[kartik.bhatia]

Yes. as I stated ... Both E1 ports up – Multiple_Frames_Established

I see the call come in to the GW as well, sh debug isdn q931 shows Number Unobtainable as the Disconnect cause code.

Any ideas please?

[linuxchild]

Hello

try to add a "." to dial peer 3

dial-peer voice 3 pots

incoming called-number

direct-inward-dial .

!!!!notice the point

if this did not work , can you do a debug voip ccapi inout , and give us the result

Regards

[kartik.bhatia]

ohh sorry ... it's a typo

I actually have a . already in there

Sorry ... should I try .T instead?

[linuxchild]

Can you give sh run

and also make a

debug voip ccapi inout

term moni (if you were in telnet or ssh)

then make a call

and post here the output of this debug

[vandana]

Also Add the port number on the following dialpeer:

dial-peer voice 3 pots

incoming called-number .T

direct-inward-dial

port 0/1/0:15

If still does not work, collect the following:

debug voip ccapi inout

debu isdn q931

[Steve Himebaugh · Accepted solution]

I don't see a dial peer sending the received call back to CallManager.  This would cause the unallocated number error if the voice gateway does not have anywhere to send the received/incoming PRI call.

Looks to me that you are stripping the leading 9 with dial peer 1.  Your VOIP dial-peer 2 sending calls to the CallManager requires a 9 for the first digit.  Does the 'debug isdn q931' show the PRI received called number beginning with a 9?  You may need to modify dial-peer 2 detination-pattern so calls will be sent back to the CallManager.  Or change dial-peer 1 to forward all digits so you get the leading 9 inbound on the PRI.

FYI ... the inbound call leg on the call from the CallManager to the voice gateway is probably matching the default dial-peer 0.

[kartik.bhatia]

Thanks Steve

Yes I already figured my stupid mistake, had a 9.T in the voip dial peer whilst I was discarding the 9 - so removed the 9 from the voip Dial Peer which fixed it.

So I do not need the incoming called-number . dial peer as well as it will match the default dial peer ?

Regards,

Kartik

[Steve Himebaugh · Accepted solution]

The incoming called number. is needed for part of the call.  It does not replace the default dial-peer. You need both.

First part of the call is from the CallManager and out of PRI port.  The inbound call leg, the VoIP, from CallManager to the voice gateway is where the default dial-peer is matched.  You can use the 'debug translation detail' to see the dial-peer matching even though you're not doing any translation.

The second part of the call is from the other PRI port back to the CallManager.  You need the 'incoming called-number.' to match the incoming call leg as in dial-peer 3.  You want to match dial-peer 3, and not the default dial-peer, so you will have direct-inward-dial.  You don't need DID on an incoming VOIP call, and there is no DID on the default dial-peer.  You do want DID on an incoming POTS call.

[linuxchild · Accepted solution]

I f you want , I have already done a back to back BRI , check it out

http://elhallak.wordpress.com/2011/06/30/dial-peer-example/

my calls go out of port 0/0/0 and return via 0/0/1

Regards

[kartik.bhatia]

hmmm ... got it now

Thanks Steve and linuxchild

[linuxchild]

you are welcome , by the way have you tried to make back to back T1 using CAS , just incase you have done it, post the answer here  https://supportforums.cisco.com/message/3392388#3392388