PRI Trunk Group not working

[Cameron Whitehead]

I am adding new PRI's to a gateway and wanted to change my dial-peer to use a trunk group instead of a port.  I created a trunk group and added it to my serial interface.

interface Serial0/1/0:23
no ip address
encapsulation hdlc
isdn switch-type primary-ni
isdn incoming-voice voice
trunk-group prigroup 1

I then added this to my Dial Peer after I removed the port command.

dial-peer voice 92 pots
trunkgroup prigroup
description Local Outbound Calling
destination-pattern 9[2-9]..[2-9]......
forward-digits 10

when I make calls I get busy signal.  I did a debug isdn q931 and found that I seem to be using the wrong "Exclusive, Channel" which I assume is the D-Cannel.

Bearer Capability i = 0x8090A2
Standard = CCITT
Transfer Capability = Speech
Transfer Mode = Circuit
Transfer Rate = 64 kbit/s
Channel ID i = 0xA98381
Exclusive, Channel 1
Calling Party Number i = 0x2181, '5551234'
Plan:ISDN, Type:National
Called Party Number i = 0xA1, '5554321'
Plan:ISDN, Type:National

When I changed it back I calls started working again and you can see the the Exclusive Channel was using the correct 23 instead.

Bearer Capability i = 0x8090A2
Standard = CCITT
Transfer Capability = Speech
Transfer Mode = Circuit
Transfer Rate = 64 kbit/s
Channel ID i = 0xA98397
Exclusive, Channel 23
Calling Party Number i = 0x2181, '5551234'
Plan:ISDN, Type:National
Called Party Number i = 0xA1, '5554321'
Plan:ISDN, Type:National

Is there something I need to do in order to get this to use the correct Channel?

[Nithin Eluvathingal]

Router(config-if)# isdn bchan-number-order {ascending | descending}

Enables B channel selection for outgoing calls on a PRI interface (optional).

Channel 1 is not the signaling   channel for T1.  You can change the B channel order using the above command from Serial interface. 

The busy is due to something else. can you share the complete debug output. 

[Roger Kallberg]

I would recommend you to configure the trunk group under the controller instead of under the serial interface. Once I’ll get to work today I can give you an example on how to do that.

[Nithin Eluvathingal · Accepted solution]

Here mentioned below is a working config with one of my customer.. Basically its for an E1 config

controller E1 0/1/0
framing no-crc4
clock source line secondary
pri-group timeslots 1-31
trunk-group VG-PRI-TRK timeslots 1-31
!

2.12.0.0

[Roger Kallberg · Accepted solution]

This is what you'd need to configure the trunk on the controller.

trunk group PRI_PSTN
 description PRI Trunk Group for PSTN calls
 hunt-scheme round-robin both down !This will depend on you needs, so please check this with you Telco before you put it in.
 translation-profile incoming PSTN-IN !Only needed if you'd want/need to do translations inbound from PSTN and wants that to be done on the trunk instead of under the voice port or dial-peer.
 translation-profile outgoing PSTN-OUT !Only needed if you'd want/need to do translations inbound to PSTN and wants that to be done on the trunk instead of under the voice port or dial-peer.
!
controller E1 0/1/0
 clock source line primary
 pri-group timeslots 1-31
 trunk-group PRI_PSTN timeslots 1-31
 description PRI to PSTN, bla bla !Add any description that you'd need/want to the controller
!
controller E1 0/1/1
 clock source line secondary
 pri-group timeslots 1-31
 trunk-group PRI_PSTN timeslots 1-31
 description PRI to PSTN, bla bla !Add any description that you'd need/want to the controller

Please note that this configuration is for an E1, if you're using a T1 you'd need to modify it to match the needs for that type of circuit.

[Cameron Whitehead]

That worked!  I had thought I tried putting it on the controller, but IOS didn't let me.  Obviously, I didn't type the command correct haha.