Cisco Support Community
Showing results for 
Search instead for 
Did you mean: 

Welcome to Cisco Support Community. We would love to have your feedback.

For an introduction to the new site, click here. If you'd prefer to explore, try our test area to get started. And see here for current known issues.

New Member

MGCP Digit trace on Gateway


I have a 2801 router with a E1 voice registered with Callmanager. I'm having various issue when dialing out. When i place a call to the gateway i cannot see any isdn circuit beign picked up, i am using debug isdn q931 for this, but when i use the debug voice ccapi inout command i can see information coming into the gateway. How do i check for the correct digits coming into the gateway with this command or should i be using another command.


Re: MGCP Digit trace on Gateway

ISDN q931 information is backhauled with if you want to see more info, I would recommend you to check CCM detailed trace.

Also debug mgcp packet is your friend. You wont see digits (unless CAS or analog) but it will show you if CCM is establishing any communication with GW, other useful command is debug ccm-manager backhaul packet.


Re: MGCP Digit trace on Gateway

When you do a 'show isdn stat' you won't see any Layer3 output. But you can use 'debug isdn q931' If you don't have output something is wrong configured.

If you want to see the channels used:

show voice call stat


show voice call sum


show mgcp connnection

You still won't see called and calling party though.


MGCP-GW1#sh isdn status

Global ISDN Switchtype = primary-net5

%Q.931 is backhauled to CCM MANAGER 0x0003 on DSL 0. Layer 3 output may not apply

ISDN Serial0/0/0:15 interface

dsl 0, interface ISDN Switchtype = primary-net5

L2 Protocol = Q.921 0x0000 L3 Protocol(s) = CCM MANAGER 0x0003

Layer 1 Status:


Layer 2 Status:


Layer 3 Status:

0 Active Layer 3 Call(s)

Active dsl 0 CCBs = 0

The Free Channel Mask: 0xFFFF7FFF

Number of L2 Discards = 0, L2 Session ID = 2

MGCP-GW1#sh voice call status

CallID CID ccVdb Port DSP/Ch Called # Codec Dial-peers

0x137CD 2DC4 0x465F7DA4 0/0/1:15.4 0/2:3 g711ulaw 1/0

0x13849 2E02 0x465F7DA4 0/0/1:15.17 0/3:4 g711ulaw 1/0

0x13D93 30A7 0x465F7DA4 0/0/1:15.24 0/4:6 g711ulaw 1/0

0x13DA9 30B2 0x465F7DA4 0/0/1:15.25 0/3:1 g711ulaw 1/0

0x13DAB 30B3 0x465F7DA4 0/0/1:15.26 0/3:3 g711ulaw 1/0

0x13DAD 30B4 0x465F7DA4 0/0/1:15.27 0/4:2 g711ulaw 1/0

0x13DFD 30DC 0x465F7DA4 0/0/1:15.29 0/1:6 g711ulaw 1/0

0x13E0B 30E3 0x465F7DA4 0/0/1:15.30 0/3:5 g711ulaw 1/0

0x13E39 30FA 0x465F7DA4 0/0/1:15.31 0/1:4 g711ulaw 1/0

0x13F15 3168 0x465F7DA4 0/0/1:15.1 0/2:4 g711ulaw 1/0

0x13F63 318F 0x465F7DA4 0/0/1:15.2 0/1:5 g711ulaw 1/0

0x140A7 3231 0x463F0648 0/0/0:15.21 0/4:3 g711ulaw 1/0

0x140BD 323C 0x463F0648 0/0/0:15.28 0/3:2 g711ulaw 1/0

0x140BF 323D 0x463F0648 0/0/0:15.26 0/2:5 g711ulaw 1/0

0x140C9 3242 0x463F0648 0/0/0:15.30 0/1:2 g711ulaw 1/0

0x140CD 3244 0x463F0648 0/0/0:15.22 0/1:3 g711ulaw 1/0

0x140CF 3245 0x463F0648 0/0/0:15.29 0/1:1 g711ulaw 1/0

0x140D1 3246 0x463F0648 0/0/0:15.27 0/2:2 g711ulaw 1/0

0x140D3 3247 0x463F0648 0/0/0:15.24 0/3:6 g711ulaw 1/0

19 active calls found


MGCP-GW1#deb isdn q931

debug isdn q931 is ON.


*Jul 17 09:32:16.374: ISDN Se0/0/0:15 Q931: TX -> SETUP pd = 8 callref = 0x1D4E

Sending Complete

Bearer Capability i = 0x8090A3

Standard = CCITT

Transfer Capability = Speech

Transfer Mode = Circuit

Transfer Rate = 64 kbit/s

Channel ID i = 0xA9839F

Exclusive, Channel 31

Calling Party Number i = 0x00A1, '805257'

Plan:Unknown, Type:Unknown

Called Party Number i = 0x80, '992876949121445'

Plan:Unknown, Type:Unk

*Jul 17 09:32:16.498: ISDN Se0/0/0:15 Q931: RX <- CALL_PROC pd = 8 callref = 0x9D4E

Channel ID i = 0xA9839F

Exclusive, Channel 31

Hope this helps,