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Walkthrough Wednesdays

PRI connectivity problem

My outbound calls are getting a busy signal and further troubleshooting indicates a problem with the PRI line.  Show isdn status indicates that the line is active.  I'm not concerned with the errors on the show controllers E1 output because they are not incrementing at an alarming rate.  However, show ip interface brief show that only serial 0/1/0:15 is up.  Any ideas on what the problem is?

Rising star

Can you capture a 'debug isdn q931' and run a test call and post the output.

When you use the E1 mode of a vwic. There will be one serial interface because its the so called "D" Channel. This is the channel that control the "B" Channels.The "B" Channels are the Channels for voice. In E1 mode in Germany for example with the ISP Telecom you must configure , the cannel Group. When you applied this the Serial Interface come up. The Serial Interface must be configured like a "BRI" Interface with some additional Settings.

So please post the settings of Controller and the settings of the Serial Interface.


Hi Philipp,

Please see requested configurations below.


controller E1 0/1/0

framing NO-CRC4

pri-group timeslots 1-31

interface Serial0/1/0:15

no ip address

encapsulation hdlc

isdn switch-type primary-net5

isdn incoming-voice voice

no cdp enable

Hi clileikis,

Sorry for the late reply.  I had to RMA the router because of a power supply failure.  Please see attaced requested debug output.  I also included the output of "show ip interface brief" to let you see that only the control channel is up on my PRI line.

May 18 07:37:39.443: ISDN Se0/1/0:15 Q931: RX <- RELEASE_COMP pd = 8  callref = 0x8081
    Cause i = 0x8295 - Call rejected

Ask you telco why, if due to wrong calling number or what.

Also, you need to configure network-clock-select.

Antonio Morales

I dont know whish country you are but using E1 tells me you are on Europe, Japan or Mexico,

Those countries have variable lenght phone numbers, on those situations you may have to specify ythe Plan and/or Type of call you try to setup.

Called Party Number i = 0x80, '3233888'
        Plan:Unknown, Type:Unknown

Like Paoulo said, contact your telco and troubleshoot with them on the phone, they can tell you what they see on their side at the moment of the setup.

To modify the plan or type use voice translation-rules and Profiles on Dial-peers or the Serial Port

voice translation-rule 10

rule 1 /^*$/ /your number/ type any national plan any isdn

voice translation-profile outgoing

translate calling 10

voice-port x/x/x:15

translation-profile outgoing outgoing

The rule define the digit manipulation

The profile define if manipulate the calling or the called number

In the voiceport you must specify if you want to use the profile in outgoing or incoming direction

one outgoing and one incoming profile per Dial-peer /Voiceport

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