Cisco IOS Release 12.0 Debug Command Reference
Debug Commands (debug ipx ipxwan - debug kerberos)

Table Of Contents

debug ipx ipxwan

Usage Guidelines

Sample Display

debug ipx nasi

Syntax Description

Usage Guidelines

Sample Display

Related Command

debug ipx packet

Usage Guidelines

Sample Display

debug ipx routing

Syntax Description

Usage Guidelines

Sample Display

Related Command

debug ipx sap

Syntax Description

Usage Guidelines

Sample Display

Related Command

debug ipx spoof

Usage Guidelines

Sample Display

debug ipx spx

Usage Guidelines

Sample Display

Related Command

debug isdn event

Usage Guidelines

Sample Displays

debug isdn q921

Usage Guidelines

Sample Displays

debug isdn q931

Usage Guidelines

Sample Displays

debug isis adj-packets

Sample Display

debug isis spf statistics

Usage Guidelines

Sample Display

debug isis update-packets

Sample Display

debug kerberos

Usage Guidelines

Sample Displays

Related Command


debug ipx ipxwan

Use the debug ipx ipxwan EXEC command to display debug information for interfaces configured to use IPXWAN. The no form of this command disables debugging output.

[no] debug ipx ipxwan

Usage Guidelines

The debug ipx ipxwan command is useful for verifying the startup negotiations between two routers running the IPX protocol through a WAN. This command produces output only during state changes or startup. During normal operations, no output is produced.

Sample Display

The following is sample output from the debug ipx ipxwan command during link startup.

Router# debug ipx ipxwan

%LINEPROTO-5-UPDOWN: Line protocol on Interface Serial1, changed state to up
IPXWAN: state (Disconnect -> Sending Timer Requests) [Serial1/6666:200 (IPX line
 state brought up)]
IPXWAN: state (Sending Timer Requests -> Disconnect) [Serial1/6666:200 (IPX line
 state brought down)]
IPXWAN: state (Disconnect -> Sending Timer Requests) [Serial1/6666:200 (IPX line
 state brought up)]

IPXWAN: Send TIMER_REQ [seq 0] out Serial1/6666:200
IPXWAN: Send TIMER_REQ [seq 1] out Serial1/6666:200
IPXWAN: Send TIMER_REQ [seq 2] out Serial1/6666:200
IPXWAN: Send TIMER_REQ [seq 0] out Serial1/6666:200

IPXWAN: Rcv TIMER_REQ on Serial1/6666:200, NodeID 1234, Seq 1
IPXWAN: Send TIMER_REQ [seq 1] out Serial1/6666:200
IPXWAN: Rcv TIMER_RSP on Serial1/6666:200, NodeID 1234, Seq 1, Del 6
IPXWAN: state (Sending Timer Requests -> Master: Sent RIP/SAP) [Serial1/6666:200
 (Received Timer Response as master)]
IPXWAN: Send RIPSAP_INFO_REQ [seq 0] out Serial1/6666:200
IPXWAN: Rcv RIPSAP_INFO_RSP from Serial1/6666:200, NodeID 1234, Seq 0
IPXWAN: state (Master: Sent RIP/SAP -> Master: Connect) [Serial1/6666:200 (Received 
Router Info Rsp as Master)]

The following line indicates that the interface has initialized:

%LINEPROTO-5-UPDOWN: Line protocol on Interface Serial1, changed state to up

The following lines indicate that the startup process failed to receive a timer response, brought the link down, then brought the link up and tried again with a new timer set:

IPXWAN: state (Sending Timer Requests -> Disconnect) [Serial1/6666:200 (IPX line
 state brought down)]
IPXWAN: state (Disconnect -> Sending Timer Requests) [Serial1/6666:200 (IPX line
 state brought up)]

The following lines indicate that the interface is sending timer requests and waiting on timer response:

IPXWAN: Send TIMER_REQ [seq 0] out Serial1/6666:200
IPXWAN: Send TIMER_REQ [seq 1] out Serial1/6666:200

The following lines indicate that the interface has received a timer request from the other end of the link and has sent a timer response. The fourth line shows that the interface has come up as the master on the link.

IPXWAN: Rcv TIMER_REQ on Serial1/6666:200, NodeID 1234, Seq 1
IPXWAN: Send TIMER_REQ [seq 1] out Serial1/6666:200
IPXWAN: Rcv TIMER_RSP on Serial1/6666:200, NodeID 1234, Seq 1, Del 6
IPXWAN: state (Sending Timer Requests -> Master: Sent RIP/SAP) [Serial1/6666:200
 (Received Timer Response as master)]

The following lines indicate that the interface is sending RIP/SAP requests:

IPXWAN: Send RIPSAP_INFO_REQ [seq 0] out Serial1/6666:200
IPXWAN: Rcv RIPSAP_INFO_RSP from Serial1/6666:200, NodeID 1234, Seq 0
IPXWAN: state (Master: Sent RIP/SAP -> Master: Connect) [Serial1/6666:200 (Received 
Router Info Rsp as Master)]

debug ipx nasi

Use the debug ipx nasi EXEC command to display information about the NetWare Asynchronous Services Interface (NASI) connections. The no form of this command disables debugging output.

[no] debug ipx nasi {packets | error | activity}

Syntax Description

packets

Displays normal operating messages relating to incoming and outgoing NASI packets. This is the default.

error

Displays messages indicating an error or failure in the protocol processing.

activity

Displays messages relating to internal NASI processing of NASI connections. The activity option includes all NASI activity such as traffic indication, timer events, and state changes.


Usage Guidelines

Use the debug ipx nasi command to display handshaking or negotiating details between the protocol (SPX or NASI) and the other protocols or applications. Use the packets option to determine the NASI traffic flow, and use the error option as a quick check of failure reasons in NASI connections.

Sample Display

The following is sample output from the debug ipx nasi command of the packet and error options.

Router# debug ipx nasi packet
Router# debug ipx nasi error

NASI0: 6E6E Check server info
NASI0: 6E6E sending server-info 4F00   Good response: 43 bytes
NASI0: 7A6E Query Port. Find first
NASI0: FFirst: line 0 DE, port: TTY1-__________ASYNC___^, group: ASYNC___^
NASI0: 7A6E sending Qport find-first response: 300 bytes
NASI0: 7B6E port request. setting up port
NASI: Check-login User: c h r i s            
NASI: Check-login PW hash: C7 A6 C5 C7 C4 C0 C5 C3 C4 CC C5 CF C4 C8 C5 CB C4 D4 C5 D7 
C4 D0 C5 D3 C4 
NASI: Check-login PW: l a b                       
NASI1: 7B6E sending NCS Good server Data Ack in 0 bytes pkt in 13 size pkt
NASI1: 7B6E sending Preq response: 303 bytes Good
NASI1: 7B6E port request. setting up port
NASI1: 7B6E sending NCS Good server Data Ack in 0 bytes pkt in 13 size pkt
NASI1: 7B6E sending Preq response: 303 bytes Good
NASI1: 7B6E Unknown NASI code 4500 Pkt Size: 13
 45 0 0 FC 0 2 0 20 0 0 FF 1 0
NASI1: 7B6E Flush Rx Buffers
NASI1: 7B6E sending NASI server TTY data: 1 byte in 14 size pkt
NASI1: 7B6E sending NCS Good server Data Ack in 1 bytes pkt in 13 size pkt

In the following line, the 0 in NASI0 is the number of the terminal (TTY) to which this NASI connection is attached. TTY 0 is used by all NASI control connections. 6E6E is the associated SPX connection pointer for this NASI connection. Check server info is a type of NASI packet that indicates an incoming NASI packet of this type.

NASI0: 6E6E Check server info

The following message indicates the router is sending back a server-info packet with a positive acknowledgment, and the packet size is 43 bytes:

NASI0: 6E6E sending server-info 4F00   Good response: 43 bytes

The following line is a NASI packet type. Find first and find next are NASI packet types.

NASI0: 7A6E Query Port. Find first

The following line indicates that the outgoing find first packet for the NASI connection 7A6E has line 0 DE, port name TTY1, and general name ASYNC:

NASI0: FFirst: line 0 DE, port: TTY1-__________ASYNC___^, group: ASYNC___^

The following two lines indicate a received NASI packet for NASI connection on line 1. 7B6E is the NASI connection pointer. The packet code is 4500 and is not recognizable by Cisco. The second line is a hexadecimal dump of the packet.

NASI1: 7B6E Unknown NASI code 4500 Pkt Size: 13
 45 0 0 FC 0 2 0 20 0 0 FF 1 0

Related Command

debug ipx spx

debug ipx packet

Use the debug ipx packet EXEC command to display information about packets received, transmitted, and forwarded. The no form of this command disables debugging output.

[no] debug ipx packet

Usage Guidelines

This command is useful for learning whether IPX packets are traveling over a router.


Note   In order to generate debug ipx packet information on all IPX traffic traveling over the router, you must first configure the router so that fast switching is disabled. Use the no ipx route-cache command on all interfaces on which you want to observe traffic. If the router is configured for IPX fast switching, only non-fast switched packets will produce output. When the IPX cache is invalidated or cleared, one packet for each destination is displayed as the cache is repopulated.


Sample Display

The following is sample output from the debug ipx packet command:

Router# debug ipx packet

IPX: src=160.0260.8c4c.4f22, dst=1.0000.0000.0001, packet received
IPX: src=160.0260.8c4c.4f22, dst=1.0000.0000.0001,gw=183.0000.0c01.5d85, 
sending packet

The first line indicates that the router receives a packet from a Novell station (address 160.0260.8c4c.4f22); this trace does not indicate the address of the immediate router sending the packet to this router. In the second line, the router forwards the packet toward the Novell server (address 1.0000.0000.0001) through an immediate router (183.0000.0c01.5d85).

describes significant fields.

Table 75 Debug IPX Packet Field Descriptions 

Field
Description

IPX

Indication that this is an IPX packet.

src = 160.0260.8c4c.4f22

Source address of the IPX packet. The Novell network number is 160. Its MAC address is 0260.8c4c.4f22.

dst = 1.0000.0000.0001

Destination address for the IPX packet. The address 0000.0000.0001 is an internal MAC address, and the network number 1 is the internal network number of a Novell 3.11 server.

packet received

The router received this packet from a Novell station, possibly through an intermediate router.

gw = 183.0000.0c01.5d85

The router is sending the packet over to the next hop router; its address of 183.0000.0c01.5d85 was learned from the IPX routing table.

sending packet

The router is attempting to send this packet.


debug ipx routing

Use the debug ipx routing EXEC command to display information on IPX routing packets that the router sends and receives. The no form of this command disables debugging output.

[no] debug ipx routing {activity | events}

Syntax Description

activity

Displays messages relating to IPX routing activity.

events

Displays messages relating to IPX routing events.


Usage Guidelines

Normally, a router or server sends out one routing update per minute. Each routing update packet can include up to 50 entries. If many networks exist on the internetwork, the router sends out multiple packets per update. For example, if a router has 120 entries in the routing table, it would send three routing update packets per update. The first routing update packet would include the first 50 entries, the second packet would include the next 50 entries, and the last routing update packet would include the last 20 entries.

Sample Display

The following is sample output from the debug ipx routing command:

Router# debug ipx routing

IPXRIP: update from 9999.0260.8c6a.1733
           110801 in 1 hops, delay 2
IPXRIP: sending update to 12FF02:ffff.ffff.ffff via Ethernet 1
           network 555, metric 2, delay 3
           network 1234, metric 3, delay 4

describes significant fields.

Table 76 Debug IPX Routing Field Descriptions 

Field
Description

IPXRIP

This is an IPX RIP packet.

update from 9999.0260.8c6a.1733

This packet is a routing update from an IPX server at address 9999.0260.8c6a.1733.

110801 in 1 hops

Network 110801 is one hop away from the router at address 9999.0260.8c6a.1733.

delay 2

Delay is a time measurement (1/18th second) that the NetWare shell uses to estimate how long to wait for a response from a file server. Also known as ticks.

sending update to 12FF02:ffff.ffff.ffff via Ethernet 1

The router is sending this IPX routing update packet to address 12FF02:ffff.ffff.ffff through its Ethernet 1 interface.

network 555

The packet includes routing update information for network 555.

metric 2

Network 555 is two metrics (or hops) away from the router.

delay 3

Network 555 is a delay of 3 away from the router. Delay is a measurement that the NetWare shell uses to estimate how long to wait for a response from a file server. Also known as ticks.


Related Command

debug ipx sap

debug ipx sap

Use the debug ipx sap EXEC command to display information about IPX Service Advertisement Protocol (SAP) packets. The no form of this command disables debugging output.

[no] debug ipx sap [activity | events]

Syntax Description

activity

(Optional) Provides more detailed output of SAP packets, including displays of services in SAP packets.

events

(Optional) Limits amount of detailed output for SAP packets to those that contain interesting events.


Usage Guidelines

Normally, a router or server sends out one SAP update per minute. Each SAP packet can include up to seven entries. If many servers are advertising on the network, the router sends out multiple packets per update. For example, if a router has 20 entries in the SAP table, it would send three SAP packets per update. The first SAP would include the first seven entries, the second SAP would include the next seven entries, and the last update would include the last six entries.

Obtain the most meaningful detail by using the debug ipx sap activity and the debug ipx sap events commands together.


Caution   
Because the debug ipx sap command can generate a lot of output, use it with caution on networks that have many interfaces and large service tables.

Sample Display

The following is sample output from the debug ipx sap command:

Router# debug ipx sap

IPXSAP: at 0023F778:
I SAP Response type 0x2 len 160 src:160.0000.0c00.070d dest:160.ffff.ffff.ffff(452)
 type 0x4, "Hello2", 199.0002.0004.0006 (451), 2 hops
 type 0x4, "Hello1", 199.0002.0004.0008 (451), 2 hops
IPXSAP: sending update to 160
IPXSAP: at 00169080:
 O SAP Update type 0x2 len 96 ssoc:0x452 dest:160.ffff.ffff.ffff(452)
IPX: type 0x4, "Magnolia", 42.0000.0000.0001 (451), 2hops

The debug ipx sap command generates multiple lines of output for each SAP packet—a packet summary message and a service detail message.

The first line displays the internal router memory address of the packet. The technical support staff may use this information in problem debugging.

IPXSAP: at 0023F778:

describes the fields shown in the second line of output.

Table 77 Debug IPX SAP Field Descriptions—Part 1 

Field
Description

I

Indication as to whether the router received the SAP packet as input (I) or is sending an update as output (O).

SAP Response type 0x2

Packet type. Format is 0xn; possible values for n include:

1—General query

2—General response

3—Get Nearest Server request

4—Get Nearest Server response

len 160

Length of this packet (in bytes).

src: 160.000.0c00.070d

Source address of the packet.

dest:160.ffff.ffff.ffff

The IPX network number and broadcast address of the destination IPX network for which the message is intended.

(452)

IPX socket number of the process sending the packet at the source address. This number is always 452, which is the socket number for the SAP process.


describes the fields shown in the third and fourth lines of output.

Table 78 Debug IPX SAP Field Descriptions—Part 2 

Field
Description

type 0x4

Indicates the type of service the server sending the packet provides. Format is 0xn. Some of the values for n are proprietary to Novell. Those values for n that have been published include

0—Unknown

1—User

2—User group

3—Print queue

4—File server

5—Job server

6—Gateway

7—Print server

8—Archive queue

9—Archive server

A—Job queue

B—Administration

21—NAS SNA gateway

24—Remote bridge server

2D—Time Synchronization VAP

2E—Dynamic SAP

47—Advertising print server

4B—Btrieve VAP 5.0

4C—SQL VAP

7A—TES—NetWare for VMS

98—NetWare access server

9A—Named Pipes server

9E—Portable NetWare—UNIX

111—Test server

166—NetWare management

233—NetWare management agent

237—NetExplorer NLM

239—HMI hub

23A—NetWare LANalyzer agent

26A—NMS management

FFFF—Wildcard (any SAP service)

Contact Novell for more information.

"HELLO2"

Name of the server being advertised.

199.0002.0004.0006 (451)

Indicates the network number and address (and socket) of the server generating the SAP packet.

2 hops

Number of hops to the server from the router.


The fifth line of output indicates that the router sent a SAP update to network 160:

IPXSAP: sending update to 160

The format for debug ipx sap output describing a SAP update the router sends is similar to that describing a SAP update the router receives, except that the ssoc: field replaces the src: field, as the following line of output indicates:

	O SAP Update type 0x2 len 96 ssoc:0x452 dest:160.ffff.ffff.ffff(452)

describes possible values for the ssoc: field.

Table 79 Debug IPX SAP Field Descriptions—Part 3 

Field
Description

ssoc:0x452

Indicates the IPX socket number of the process sending the packet at the source address. Possible values include

451—Network Core Protocol

452—Service Advertising Protocol

453—Routing Information Protocol

455—NetBIOS

456—Diagnostics

4000 to 6000—Ephemeral sockets used for interaction with file servers and other network communications


Related Command

debug ipx routing

debug ipx spoof

Use the debug ipx spoof EXEC command to display information about SPX keepalive and IPX watchdog packets when ipx watchdog and ipx spx-spoof are configured on the router. The no form of this command disables debugging output.

[no] debug ipx spoof

Usage Guidelines

Use this command to troubleshoot connections that use sequential packet exchange (SPX) spoofing when SPX keepalive spoofing is enabled.

Sample Display

The following is sample output from the debug ipx spoof command:

Router# debug ipx spoof 

IPX: Tu1:200.0260.8c8d.da75->CC0001.0000.0000.0001 ln= 42 tc=02, SPX: 80 0 7004 4B8 8 
1D 23 (new) (changed:yes) Last Changed 0
IPX: Tu1:200.0260.8c8d.c558->CC0001.0000.0000.0001 ln= 42 tc=02, SPX: 80 0 7104 2B8 7 
29 2E (new) (changed:yes) Last Changed 0

IPX: Et1:CC0001.0000.0000.0001->200.0260.8c8d.c558 ln= 42 tc=02, SPX: 80 0 2B8 7104 29 
7 7 (early)
IPX: Et1:CC0001.0000.0000.0001->200.0260.8c8d.da75 ln= 42 tc=02, SPX: 80 0 4B8 7004 1D 
8 8 (early)
IPX: Et1:CC0001.0000.0000.0001->200.0260.8c8d.da75 ln= 32 tc=02, watchdog
IPX: local:200.0260.8c8d.da75->CC0001.0000.0000.0001 ln= 32 tc=00, watchdog snet
IPX: Tu1:200.0260.8c8d.da75->CC0001.0000.0000.0001 ln= 42 tc=02, SPX: 80 0 7004 4B8 8 
1D 23 (changed:clear) Last Changed 0
IPX: Et1:CC0001.0000.0000.0001->200.0260.8c8d.c558 ln= 42 tc=02, SPX: C0 0 2B8 7104 29 
7 7 (early)
IPX: Tu1:200.0260.8c8d.c558->CC0001.0000.0000.0001 ln= 42 tc=02, SPX: 80 0 7104 2B8 7 
29 2E (changed:clear) Last Changed 0
IPX: Et1:CC0001.0000.0000.0001->200.0260.8c8d.c558 ln= 42 tc=02, SPX: C0 0 2B8 7104 29 
7 7 (Last Changed 272 sec)
IPX: local:200.0260.8c8d.c558->CC0001.0000.0000.0001 ln= 42 tc=02, spx keepalive sent 
80 0 7104 2B8 7 29 2E

The following lines show that SPX packets were seen, but they are not seen for a connection that exists in the SPX table:

IPX: Tu1:200.0260.8c8d.da75->CC0001.0000.0000.0001 ln= 42 tc=02, SPX: 80 0 7004 4B8 8 
1D 23 (new) (changed:yes) Last Changed 0
IPX: Tu1:200.0260.8c8d.c558->CC0001.0000.0000.0001 ln= 42 tc=02, SPX: 80 0 7104 2B8 7 
29 2E (new) (changed:yes) Last Changed 0

The following lines show SPX packets are for connections that exist in the SPX table but SPX idle time has not yet elapsed and spoofing has not started:

IPX: Et1:CC0001.0000.0000.0001->200.0260.8c8d.c558 ln= 42 tc=02, SPX: 80 0 2B8 7104 29 
7 7 (early)
IPX: Et1:CC0001.0000.0000.0001->200.0260.8c8d.da75 ln= 42 tc=02, SPX: 80 0 4B8 7004 1D 
8 8 (early)

The following lines show an IPX watchdog packet and the spoofed reply:

IPX: Et1:CC0001.0000.0000.0001->200.0260.8c8d.da75 ln= 32 tc=02, watchdog
IPX: local:200.0260.8c8d.da75->CC0001.0000.0000.0001 ln= 32 tc=00, watchdog sent

The following lines show SPX packets that arrived more than two minutes after spoofing started. This situation occurs when the other sides of the SPX table are cleared. When the table is cleared, the routing processes stop spoofing the connection, which allows SPX keepalives from the local side to travel to the remote side and repopulate the SPX table.

IPX: Tu1:200.0260.8c8d.da75->CC0001.0000.0000.0001 ln= 42 tc=02, SPX: 80 0 7004 4B8 8 
1D 23 (changed:clear) Last Changed 0
IPX: Et1:CC0001.0000.0000.0001->200.0260.8c8d.c558 ln= 42 tc=02, SPX: C0 0 2B8 7104 29 
7 7 (early)
IPX: Tu1:200.0260.8c8d.c558->CC0001.0000.0000.0001 ln= 42 tc=02, SPX: 80 0 7104 2B8 7 
29 2E (changed:clear) Last Changed 0

The following lines show that an SPX keepalive packet came in and was spoofed:

IPX: Et1:CC0001.0000.0000.0001->200.0260.8c8d.c558 ln= 42 tc=02, SPX: C0 0 2B8 7104 29 
7 7 (Last Changed 272 sec)
IPX: local:200.0260.8c8d.c558->CC0001.0000.0000.0001 ln= 42 tc=02, spx keepalive sent 
80 0 7104 2B8 7 29 2E

debug ipx spx

Use the debug ipx spx EXEC command to display debugging messages related to the Sequenced Packet Exchange (SPX) protocol. The no form of this command disables debugging output.

[no] debug ipx spx

Usage Guidelines

Use the debug ipx spx command to display handshaking or negotiating details between the SPX protocol and the other protocols or applications. SPX debugging messages indicate various states of SPX connections such as incoming and outgoing traffic information, timer events, and related processing of SPX connections.

Sample Display

The following is sample output from the debug ipx spx command:

Router# debug ipx spx

SPX: Sent an SPX packet
SPX: I Con Src/Dst 776E/20A0 d-strm 0 con-ctl 80
SPX: I Con Src/Dst 776E/20A0 d-strm FE con-ctl 40
SPX: C847C Connection close requested by peer
SPX: Sent an SPX packet
SPX: purge timer fired. Cleaning up C847C
SPX: purging spxcon C847C from conQ
SPX: returning inQ buffers
SPX: returning outQ buffers
SPX: returning unackedQ buffers
SPX: returning spxcon
SPX: I Con Src/Dst 786E/FFFF d-strm 0 con-ctl C0
SPX: new connection request for listening socket
SPX: Sent an SPX packet
SPX: I Con Src/Dst 786E/20B0 d-strm 0 con-ctl 40
SPX: 300 bytes data recvd
SPX: Sent an SPX packet

The following line indicates an incoming SPX packet that has a source connection ID of 776E and a destination connection ID of 20A0 (both in hexadecimal). The data stream value in the SPX packet is indicated by d-strm, and the connection control value in the SPX packet is indicated by con-ctl (both in hexadecimal). All data packets received are followed by an SPX debug message indicating the size of the packet. All control packets received are consumed internally.

SPX: I Con Src/Dst 776E/20A0 d-strm 0 con-ctl 80

The following lines indicate that SPX is attempting to remove an SPX connection that has the address C8476 from its list of connections:

SPX: purge timer fired. Cleaning up C847C
SPX: purging spxcon C847C from conQ

Related Command

debug ipx nasi

debug isdn event

Use the debug isdn event EXEC command to display Integrated Services Digital Network (ISDN) events occurring on the user side (on the router) of the ISDN interface. The ISDN events that can be displayed are Q.931 events (call setup and teardown of ISDN network connections). The no form of this command disables debugging output.

[no] debug isdn event

Usage Guidelines

Although the debug isdn event and the debug isdn q931 commands provide similar debug information, the information is displayed in a different format. If you want to see the information in both formats, enable both commands at the same time. The displays will be intermingled.

Use the show dialer command to retrieve information about the status and configuration of the ISDN interface on the router.

Use the service timestamps debug datetime msec global configuration command to include the time with each message.

For more information on ISDN switch types, codes, and values, refer to Appendix B, "ISDN Switch Types, Codes, and Values."

Sample Displays

The following is sample output from the debug isdn event command of call setup events for an outgoing call.

Router# debug isdn event

ISDN Event: Call to 415555121202
received HOST_PROCEEDING
 Channel ID i = 0x0101
 -------------------
 Channel ID i = 0x89
received HOST_CONNECT
 Channel ID i = 0x0101
ISDN Event: Connected to 415555121202 on B1 at 64 Kb/s

The following shows sample debug isdn event output of call setup events for an incoming call. The values used for internal purposes are unpacked information elements. The values that follow the ISDN specification are an interpretation of the unpacked information elements. Refer to Appendix B, "ISDN Switch Types, Codes, and Values," for information about these values.

Router# debug isdn event

received HOST_INCOMING_CALL
 Bearer Capability i = 0x080010
 -------------------
 Channel ID i = 0x0101
 Calling Party Number i = 0x0000, `415555121202'
 IE out of order or end of `private' IEs --
 Bearer Capability i = 0x8890
 Channel ID i = 0x89
 Calling Party Number i = 0x0083, `415555121202'
ISDN Event: Received a call from 415555121202 on B1 at 64 Kb/s
ISDN Event: Accepting the call
received HOST_CONNECT
 Channel ID i = 0x0101
ISDN Event: Connected to 415555121202 on B1 at 64 Kb/s

The following is sample output from the debug isdn event command of call teardown events for a call that has been disconnected by the host side of the connection.

Router# debug isdn event

received HOST_DISCONNECT
ISDN Event: Call to 415555121202 was hung up

The following is sample output from the debug isdn event command of a call teardown event for an outgoing or incoming call that has been disconnected by the ISDN interface on the router side.

Router# debug isdn event

ISDN Event: Hangup call to call id 0x8008

describes significant fields shown.

Table 80 Debug ISDN Event Field Descriptions 

Field
Description

Bearer Capability

Indicates the requested bearer service to be provided by the network. Refer to Table B-4 in the "ISDN Switch Types, Codes, and Values" appendix for detailed information about bearer capability values.

i=

Indicates the Information Element Identifier. The value depends on the field it is associated with. Refer to the ITU-T1 Q.931 specification for details about the possible values associated with each field for which this identifier is relevant.

Channel ID

Channel Identifier. The values and corresponding channels might be identified in several ways:
Channel ID i = 0x0101—Channel B1
Channel ID i = 0x0102—Channel B2

ITU-T Q.931 defines the values and channels as exclusive or preferred:
Channel ID i = 0x83—Any B-channel
Channel ID i = 0x89—Channel B1 (exclusive)
Channel ID i = 0x8A—Channel B2 (exclusive)

Channel ID i = 0x81—B1 (preferred)
Channel ID i = 0x82—B2 (preferred)

Calling Party Number

Identifies the called party. This field is only present in outgoing calls. The Calling Party Number field uses the IA5 character set. Note that it may be replaced by the Keypad facility field.

IE out of order or end of `private' IEs

Indicates that an information element identifier is out of order or there are no more private network information element identifiers to interpret.

Received a call from 415555121202 on B1 at 64Kb/s

Identifies the origin of the call. This field is present only in incoming calls. Note that the information about the incoming call includes the channel and speed. Whether the channel and speed are displayed depends on the network delivering the calling party number.

1 The ITU-T carries out the functions of the former Consultative Committee for International Telegraph and Telephone.


The following is sample output from the debug isdn event command of a call teardown event for a call that has passed call screening then has been hung up by the ISDN interface on the far end side.

Router# debug isdn event

Jan  3 11:29:52.559: ISDN BR0: RX <-  DISCONNECT pd = 8  callref = 0x81
Jan  3 11:29:52.563:         Cause i = 0x8090 - Normal call clearing 

The following is sample output from the debug isdn event command of a call teardown event for a call that has not passed call screening and has been rejected by the ISDN interface on the router side.

Router# debug isdn event

Jan  3 11:32:03.263: ISDN BR0: RX <-  DISCONNECT pd = 8  callref = 0x85
Jan  3 11:32:03.267:         Cause i = 0x8095 - Call rejected

The following is sample output from the debug isdn event command of a call teardown event for an outgoing call that uses a dialer subaddress.

Router# debug isdn event

Jan  3 11:41:48.483: ISDN BR0: Event: Call to 61885:1212 at 64 Kb/s
Jan  3 11:41:48.495: ISDN BR0: TX ->  SETUP pd = 8  callref = 0x04
Jan  3 11:41:48.495:         Bearer Capability i = 0x8890
Jan  3 11:41:48.499:         Channel ID i = 0x83
Jan  3 11:41:48.503:         Called Party Number i = 0x80, '61885'
Jan  3 11:41:48.507:         Called Party SubAddr i = 0x80, 'P1212'
Jan  3 11:41:48.571: ISDN BR0: RX <-  CALL_PROC pd = 8  callref = 0x84
Jan  3 11:41:48.575:         Channel ID i = 0x89
Jan  3 11:41:48.587: ISDN BR0: Event: incoming ces value = 1
Jan  3 11:41:48.587: ISDN BR0: received HOST_PROCEEDING
                        Channel ID i = 0x0101
Jan  3 11:41:48.591:    -------------------
                        Channel ID i = 0x89
Jan  3 11:41:48.731: ISDN BR0: RX <-  CONNECT pd = 8  callref = 0x84
Jan  3 11:41:48.743: ISDN BR0: Event: incoming ces value = 1
Jan  3 11:41:48.743: ISDN BR0: received HOST_CONNECT
                        Channel ID i = 0x0101
Jan  3 11:41:48.747:    -------------------
%LINK-3-UPDOWN: Interface BRI0:1 changed state to up
Jan  3 11:41:48.771: ISDN BR0: Event: Connected to 61885:1212 on B1 at 64 Kb/s
Jan  3 11:41:48.775: ISDN BR0: TX ->  CONNECT_ACK pd = 8  callref = 0x04
%LINEPROTO-5-UPDOWN: Line protocol on Interface BRI0:1, changed state to up
%ISDN-6-CONNECT: Interface BRI0:1 is now connected to 61885:1212 goodie

The output is similar to the output of debug isdn q931. Refer to the debug isdn q931 command for detailed field descriptions.

The following is sample output from the debug isdn event command of call setup events for a successful callback for legacy DDR.

Router# debug isdn event

BRI0:Caller id Callback server starting to spanky 81012345678902
: Callback timer expired
BRI0:beginning callback to spanky 81012345678902
BRI0: Attempting to dial 81012345678902

The following is sample output from the debug isdn event command for a callback that was unsuccessful because the router had no dialer map for the calling number.

Router# debug isdn event

BRI0:Caller id 81012345678902 callback - no matching map

describes significant fields.

Table 81 Debug ISDN Event Field Descriptions for Caller ID Callback and Legacy DDR

Field
Description

BRI0:Caller id Callback server starting to ...

Caller ID callback has started, plus host name and number called. The callback enable timer starts now.

: Callback timer expired

Callback timer has expired; callback can proceed.

BRI0:beginning callback to ...
BRI0: Attempting to dial ...

Actions proceeding after the callback timer expired, plus host name and number called.


The following is sample output from the debug isdn event command for a callback that was successful when the dialer profiles DDR feature is configured.

*Mar  1 00:46:51.827: BR0:1:Caller id 81012345678901 matched to profile delorean
*Mar  1 00:46:51.827: Dialer1:Caller id Callback server starting to delorean 81012345678901
*Mar  1 00:46:54.151: : Callback timer expired
*Mar  1 00:46:54.151: Dialer1:beginning callback to delorean 81012345678901
*Mar  1 00:46:54.155: Freeing callback to delorean 81012345678901
*Mar  1 00:46:54.155: BRI0: Dialing cause Callback return call
*Mar  1 00:46:54.155: BRI0: Attempting to dial 81012345678901
*Mar  1 00:46:54.503: %LINK-3-UPDOWN: Interface BRI0:2, changed state to up
*Mar  1 00:46:54.523: %DIALER-6-BIND: Interface BRI0:2 bound to profile Dialer1
*Mar  1 00:46:55.139: %LINEPROTO-5-UPDOWN: Line protocol on Interface BRI0:2, changed state to up
*Mar  1 00:46:58.187: %ISDN-6-CONNECT: Interface BRI0:2 is now connected to 81012345678901 delorean

describes significant fields of call setup events for a successful call back for the sample output from the debug isdn event command when the dialer profiles DDR feature is configured.

Table 82 Debug ISDN Event Field Descriptions for Caller ID Callback and Dialer Profiles 

Field
Description

BR0:1:Caller id ... matched to profile ...

Interface, channel number, caller ID that is matched, and the profile to bind to the interface.

: Callback timer expired

Callback timer has expired; callback can proceed.

Dialer1:beginning callback to...

Callback process is beginning to the specified number.

Freeing callback to...

Callback has been started to the specified number, and the number has been removed from the callback list.

BRI0: Dialing cause Callback return call
BRI0: Attempting to dial

The reason for the call and the number being dialed.

%LINK-3-UPDOWN: Interface BRI0:2, changed state to up

Interface status: up.

%DIALER-6-BIND: Interface BRI0:2 bound to profile Dialer1

Profile bound to the interface.

%LINEPROTO-5-UPDOWN: Line protocol on Interface BRI0:2, changed state to up

Line protocol status: up.

%ISDN-6-CONNECT: Interface BRI0:2 is now connected to ...

Interface is now connected to the specified host and number.


debug isdn q921

Use the debug isdn q921 EXEC command to display data link layer (Layer 2) access procedures that are taking place at the router on the D channel (LAPD) of its Integrated Services Digital Network (ISDN) interface. The no form of this command disables debugging output.

[no] debug isdn q921

Usage Guidelines

The ISDN data link layer interface provided by the router conforms to the user interface specification defined by ITU-T recommendation Q.921. The debug isdn q921 command output is limited to commands and responses exchanged during peer-to-peer communication carried over the D channel. This debug information does not include data transmitted over the B channels that are also part of the router's ISDN interface. The peers (data link layer entities and layer management entities on the routers) communicate with each other via an ISDN switch over the D channel.


Note   The ISDN switch provides the network interface defined by Q.921. This debug command does not display data link layer access procedures taking place within the ISDN network (that is, procedures taking place on the network side of the ISDN connection). See Appendix B, "ISDN Switch Types, Codes, and Values," for a list of the supported ISDN switch types.


A router can be the calling or called party of the ISDN Q.921 data link layer access procedures. If the router is the calling party, the command displays information about an outgoing call. If the router is the called party, the command displays information about an incoming call and the keepalives.

The debug isdn q921 command can be used with the debug isdn event and the debug isdn q931 commands at the same time. The displays will be intermingled.

Use the service timestamps debug datetime msec global configuration command to include the time with each message.

For more information on ISDN switch types, codes, and values, refer to Appendix B, "ISDN Switch Types, Codes, and Values."

Sample Displays

The following is sample output from the debug isdn q921 command for an outgoing call.

Router# debug isdn q921

Jan  3 14:52:24.475: ISDN BR0: TX ->  INFOc sapi = 0  tei = 64  ns = 5  nr = 2
                              i = 0x08010705040288901801837006803631383835
Jan  3 14:52:24.503: ISDN BR0: RX <-  RRr sapi = 0  tei = 64  nr = 6
Jan  3 14:52:24.527: ISDN BR0: RX <-  INFOc sapi = 0  tei = 64  ns = 2  nr = 6
                              i = 0x08018702180189
Jan  3 14:52:24.535: ISDN BR0: TX ->  RRr sapi = 0  tei = 64  nr = 3
Jan  3 14:52:24.643: ISDN BR0: RX <-  INFOc sapi = 0  tei = 64  ns = 3  nr = 6
                              i = 0x08018707
Jan  3 14:52:24.655: ISDN BR0: TX ->  RRr sapi = 0  tei = 64  nr = 4
%LINK-3-UPDOWN: Interface BRI0:1, changed state to up
Jan  3 14:52:24.683: ISDN BR0: TX ->  INFOc sapi = 0  tei = 64  ns = 6  nr = 4
                              i = 0x0801070F
Jan  3 14:52:24.699: ISDN BR0: RX <-  RRr sapi = 0  tei = 64  nr = 7
%LINEPROTO-5-UPDOWN: Line protocol on Interface BRI0:1, changed state to up
%ISDN-6-CONNECT: Interface BRI0:1 is now connected to 61885 goodie
Jan  3 14:52:34.415: ISDN BR0: RX <-  RRp sapi = 0  tei = 64 nr = 7 
Jan  3 14:52:34.419: ISDN BR0: TX ->  RRf sapi = 0  tei = 64  nr = 4

In the following lines, the seventh and eighth most significant hexadecimal numbers indicate the type of message. 0x05 indicates a Call Setup message, 0x02 indicates a Call Proceeding message, 0x07 indicates a Call Connect message, and 0x0F indicates a Connect Ack message.

Jan  3 14:52:24.475: ISDN BR0: TX ->  INFOc sapi = 0  tei = 64  ns = 5  nr = 2
                              i = 0x08010705040288901801837006803631383835
Jan  3 14:52:24.527: ISDN BR0: RX <-  INFOc sapi = 0  tei = 64  ns = 2  nr = 6
                              i = 0x08018702180189
Jan  3 14:52:24.643: ISDN BR0: RX <-  INFOc sapi = 0  tei = 64  ns = 3  nr = 6
                              i = 0x08018707
Jan  3 14:52:24.683: ISDN BR0: TX ->  INFOc sapi = 0  tei = 64  ns = 6  nr = 4
                              i = 0x0801070F

The following is sample output from the debug isdn q921 command for a startup message on a DMS-100 switch.

Router# debug isdn q921

Jan  3 14:47:28.455: ISDN BR0: RX <-  IDCKRQ  ri = 0  ai = 127 0
Jan  3 14:47:30.171: ISDN BR0: TX ->  IDREQ  ri = 31815  ai = 127 
Jan  3 14:47:30.219: ISDN BR0: RX <-  IDASSN  ri = 31815  ai = 64 
Jan  3 14:47:30.223: ISDN BR0: TX ->  SABMEp sapi = 0  tei = 64
Jan  3 14:47:30.227: ISDN BR0: RX <-  IDCKRQ  ri = 0  ai = 127 
Jan  3 14:47:30.235: ISDN BR0: TX ->  IDCKRP  ri = 16568  ai = 64 
Jan  3 14:47:30.239: ISDN BR0: RX <-  UAf sapi = 0  tei = 64
Jan  3 14:47:30.247: ISDN BR0: TX ->  INFOc sapi = 0  tei = 64  ns = 0  nr = 0
                              i = 0x08007B3A03313233
Jan  3 14:47:30.267: ISDN BR0: RX <-  RRr sapi = 0  tei = 64  nr = 1
Jan  3 14:47:34.243: ISDN BR0: TX ->  INFOc sapi = 0  tei = 64  ns = 1  nr = 0
                              i = 0x08007B3A03313233
Jan  3 14:47:34.267: ISDN BR0: RX <-  RRr sapi = 0  tei = 64  nr = 2
Jan  3 14:47:43.815: ISDN BR0: RX <-  RRp sapi = 0  tei = 64 nr = 2 
Jan  3 14:47:43.819: ISDN BR0: TX ->  RRf sapi = 0  tei = 64  nr = 0
Jan  3 14:47:53.819: ISDN BR0: TX ->  RRp sapi = 0  tei = 64 nr = 0 

The first seven lines of this example indicate an L2 link establishment.

The following lines indicate the message exchanges between the data link layer entity on the local router (user side) and the assignment source point (ASP) on the network side during the TEI assignment procedure. This assumes that the link is down and no TEI currently exists.

Jan  3 14:47:30.171: ISDN BR0: TX ->  IDREQ  ri = 31815  ai = 127 
Jan  3 14:47:30.219: ISDN BR0: RX <-  IDASSN  ri = 31815  ai = 64 

At 14:47:30.171, the local router data link layer entity sent an Identity Request message to the network data link layer entity to request a TEI value that can be used in subsequent communication between the peer data link layer entities. The request includes a randomly generated reference number (31815) to differentiate among user devices that request automatic TEI assignment and an action indicator of 127 to indicate that the ASP can assign any TEI value available. The ISDN user interface on the router uses automatic TEI assignment.

At 14:47:30.219, the network data link entity responds to the Identity Request message with an Identity Assigned message. The response includes the reference number (31815) previously sent in the request and TEI value (64) assigned by the ASP.

The following lines indicate the message exchanges between the layer management entity on the network and the layer management entity on the local router (user side) during the TEI check procedure:

Jan  3 14:47:30.227: ISDN BR0: RX <-  IDCKRQ  ri = 0  ai = 127 
Jan  3 14:47:30.235: ISDN BR0: TX ->  IDCKRP  ri = 16568  ai = 64 

At 14:47:30.227, the layer management entity on the network sends the Identity Check Request message to the layer management entity on the local router to check whether a TEI is in use. The message includes a reference number that is always 0 and the TEI value to check. In this case, an ai value of 127 indicates that all TEI values should be checked. At 14:47:30.227, the layer management entity on the local router responds with an Identity Check Response message indicating that TEI value 64 is currently in use.

The following lines indicate the messages exchanged between the data link layer entity on the local router (user side) and the data link layer on the network side to place the network side into modulo 128 multiple frame acknowledged operation. Note that the data link layer entity on the network side also can initiate the exchange.

Jan  3 14:47:30.223: ISDN BR0: TX ->  SABMEp sapi = 0  tei = 64
Jan  3 14:47:30.239: ISDN BR0: RX <-  UAf sapi = 0  tei = 64

At 14:47:30.223, the data link layer entity on the local router sends the SABME command with a SAPI of 0 (call control procedure) for TEI 64. At 14:47:30.239, the first opportunity, the data link layer entity on the network responds with a UA response. This response indicates acceptance of the command. The data link layer entity sending the SABME command may have to send it more than once before receiving a UA response.

The following lines indicate the status of the data link layer entities. Both are ready to receive I frames.

Jan  3 14:47:43.815: ISDN BR0: RX <-  RRp sapi = 0  tei = 64 nr = 2 
Jan  3 14:47:43.819: ISDN BR0: TX ->  RRf sapi = 0  tei = 64  nr = 0

These I frames are typically exchanged every 10 seconds (T203 timer).

The following is sample output from the debug isdn q921 command for an incoming call. It is an incoming SETUP message that assumes the L2 link is already established to the other side.

Router# debug isdn q921

Jan  3 14:49:22.507: ISDN BR0: TX ->  RRp sapi = 0  tei = 64 nr = 0 
Jan  3 14:49:22.523: ISDN BR0: RX <-  RRf sapi = 0  tei = 64  nr = 2
Jan  3 14:49:32.527: ISDN BR0: TX ->  RRp sapi = 0  tei = 64 nr = 0 
Jan  3 14:49:32.543: ISDN BR0: RX <-  RRf sapi = 0  tei = 64  nr = 2
Jan  3 14:49:42.067: ISDN BR0: RX <-  RRp sapi = 0  tei = 64 nr = 2 
Jan  3 14:49:42.071: ISDN BR0: TX ->  RRf sapi = 0  tei = 64  nr = 0
Jan  3 14:49:47.307: ISDN BR0: RX <-  UI sapi = 0  tei = 127
                              i = 0x08011F05040288901801897006C13631383836
%LINK-3-UPDOWN: Interface BRI0:1, changed state to up
Jan  3 14:49:47.347: ISDN BR0: TX ->  INFOc sapi = 0  tei = 64  ns = 2  nr = 0
                              i = 0x08019F07180189
Jan  3 14:49:47.367: ISDN BR0: RX <-  RRr sapi = 0  tei = 64  nr = 3
Jan  3 14:49:47.383: ISDN BR0: RX <-  INFOc sapi = 0  tei = 64  ns = 0  nr = 3
                              i = 0x08011F0F180189
Jan  3 14:49:47.391: ISDN BR0: TX ->  RRr sapi = 0  tei = 64  nr = 1
%LINEPROTO-5-UPDOWN: Line protocol on Interface BRI0:1, changed state to up

describes significant fields shown.

Table 83 Debug ISDN Q921 Field Descriptions 

Field
Description

Jan 3 14:49:47.391

Indicates the date and time at which the frame was transmitted from or received by the data link layer entity on the router. The time is maintained by an internal clock.

TX

Indicates that this frame is being transmitted from the ISDN interface on the local router (user side).

RX

Indicates that this frame is being received by the ISDN interface on the local router from the peer (network side).

IDREQ

Indicates the Identity Request message type sent from the local router to the network (assignment source point [ASP]) during the automatic terminal endpoint identifier (TEI) assignment procedure. This message is sent in a UI command frame. The service access point identifier (SAPI) value for this message type is always 63 (indicating that it is a Layer 2 management procedure) but it is not displayed. The TEI value for this message type is 127 (indicating that it is a broadcast operation).

ri = 31815

Indicates the Reference number used to differentiate between user devices requesting TEI assignment. This value is a randomly generated number between 0 and 65535. The same ri value sent in the IDREQ message should be returned in the corresponding IDASSN message. Note that a Reference number of 0 indicates that the message is sent from the network side management layer entity and a reference number has not been generated.

ai = 127

Indicates the Action indicator used to request that the ASP assign any TEI value. It is always 127 for the broadcast TEI. Note that in some message types, such as IDREM, a specific TEI value is indicated.

IDREM

Indicates the Identity Remove message type sent from the ASP to the user side layer management entity during the TEI removal procedure. This message is sent in a UI command frame. The message includes a reference number that is always 0, because it is not responding to a request from the local router. The ASP sends the Identity Remove message twice to avoid message loss.

IDASSN

Indicates the Identity Assigned message type sent from the ISDN service provider on the network to the local router during the automatic TEI assignment procedure. This message is sent in a UI command frame. The SAPI value for this message type is always 63 (indicating that it is a Layer 2 management procedure). The TEI value for this message type is 127 (indicating it is a broadcast operation).

ai = 64

Indicates the TEI value automatically assigned by the ASP. This TEI value is used by data link layer entities on the local router in subsequent communication with the network. The valid values are in the range 64 to 126.

SABME

Indicates the set asynchronous balanced mode extended command. This command places the recipient into modulo 128 multiple frame acknowledged operation. This command also indicates that all exception conditions have been cleared. The SABME command is sent once a second for N200 times (typically three times) until its acceptance is confirmed with a UA response. For a list and brief description of other commands and responses that can be exchanged between the data link layer entities on the local router and the network, see ITU-T Recommendation Q.921.

sapi = 0

Identifies the service access point at which the data link layer entity provides services to Layer 3 or to the management layer. A SAPI with the value 0 indicates it is a call control procedure. Note that the Layer 2 management procedures such as TEI assignment, TEI removal, and TEI checking, which are tracked with the debug isdn q921 command, do not display the corresponding SAPI value; it is implicit. If the SAPI value were displayed it would be 63.

tei = 64

Indicates the TEI value automatically assigned by the ASP. This TEI value will be used by data link layer entities on the local router in subsequent communication with the network. The valid values are in the range 64 to 126.

IDCKRQ

Indicates the Identity Check Request message type sent from the ISDN service provider on the network to the local router during the TEI check procedure. This message is sent in a UI command frame. The ri field is always 0. The ai field for this message contains either a specific TEI value for the local router to check or 127, which indicates that the local router should check all TEI values. For a list and brief description of other message types that can be exchanged between the local router and the ISDN service provider on the network, see Appendix B, "ISDN Switch Types, Codes, and Values."

IDCKRP

Indicates the Identity Check Response message type sent from the local router to the ISDN service provider on the network during the TEI check procedure. This message is sent in a UI command frame in response to the IDCKRQ message. The ri field is a randomly generated number between 0 and 65535. The ai field for this message contains the specific TEI value that has been checked.

UAf

Confirms that the network side has accepted the SABME command previously sent by the local router. The final bit is set to 1.

INFOc

Indicates that this is an Information command. It is used to transfer sequentially numbered frames containing information fields that are provided by Layer 3. The information is transferred across a datalink connection.

INFORMATION pd = 8 callref = (null)

Indicates the information fields provided by Layer 3. The information is sent one frame at a time. If multiple frames need to be sent, several Information commands are sent. The pd value is the protocol discriminator. The value 8 indicates it is call control information. The call reference number is always null for SPID information.

SPID information i = 0x343135393033383336363031

Indicates the service profile identifier (SPID). The local router sends this information to the ISDN switch to indicate the services to which it subscribes. SPIDs are assigned by the service provider and are usually 10-digit telephone numbers followed by optional numbers. Currently, only the DMS-100 switch supports SPIDs, one for each B channel. If SPID information is sent to a switch type other than DMS-100, an error may be displayed in the debug information.

ns = 0

Indicates the send sequence number of transmitted I frames.

nr = 0

Indicates the expected send sequence number of the next received I frame. At time of transmission, this value should be equal to the value of ns. The value of nr is used to determine whether frames need to be retransmitted for recovery.

RRr

Indicates the Receive Ready response for unacknowledged information transfer. The RRr is a response to an INFOc.

RRp

Indicates the Receive Ready command with the poll bit set. The data link layer entity on the user side uses the poll bit in the frame to solicit a response from the peer on the network side.

RRf

Indicates the Receive Ready response with the final bit set. The data link layer entity on the network side uses the final bit in the frame to indicate a response to the poll.

sapi

Indicates the service access point identifier. The SAPI is the point at which data link services are provided to a network layer or management entity. Currently, this field can have the value 0 (for call control procedure) or 63 (for Layer 2 management procedures).

tei

Indicates the terminal endpoint identifier (TEI) that has been assigned automatically by the assignment source point (ASP) (also called the layer management entity on the network side). The valid range is 64 to 126. The value 127 indicates a broadcast.


debug isdn q931

Use the debug isdn q931 EXEC command to display information about call setup and teardown of ISDN network connections (Layer 3) between the local router (user side) and the network. The no form of this command disables debugging output.

[no] debug isdn q931

Usage Guidelines

The ISDN network layer interface provided by the router conforms to the user interface specification defined by ITU-T recommendation Q.931, supplemented by other specifications such as for switch type VN4. The router tracks only activities that occur on the user side, not the network side, of the network connection. The display information debug isdn q931 command output is limited to commands and responses exchanged during peer-to-peer communication carried over the D channel. This debug information does not include data transmitted over the B channels, which are also part of the router's ISDN interface. The peers (network layers) communicate with each other via an ISDN switch over the D channel.

A router can be the calling or called party of the ISDN Q.931 network connection call setup and tear- down procedures. If the router is the calling party, the command displays information about an outgoing call. If the router is the called party, the command displays information about an incoming call.

You can use the debug isdn q931 command with the debug isdn event and the debug isdn q921 commands at the same time. The displays will be intermingled. Use the service timestamps debug datetime msec global configuration command to include the time with each message.

For more information on ISDN switch types, codes, and values, refer to Appendix B, "ISDN Switch Types, Codes, and Values.".

Sample Displays

The following is sample output from the debug isdn q931 command of a call setup procedure for an outgoing call.

Router# debug isdn q931

TX -> SETUP pd = 8 callref = 0x04
 Bearer Capability i = 0x8890
 Channel ID i = 0x83
 Called Party Number i = 0x80, `4