User manual
ISDN BR0: TX -> IDREQ ri = 1708 ai = 127
ISDN BR0: RX <- IDASSN ri = 1708 ai = 85
ISDN BR0: TX -> SABMEp sapi = 0 tei = 85
ISDN BR0: RX <- UAf sapi = 0 tei = 85
ISDN BR0: TX -> INFOc sapi = 0 tei = 85 ns = 0 nr = 0 i = 0x08007B3A0A30383335383636323031
ISDN BR0: RX <- INFOc sapi = 0 tei = 85 ns = 0 nr = 1 i = 0x08007B080382E43A
ISDN BR0: TX -> RRr sapi = 0 tei = 85 nr = 1
ISDN BR0: TX -> IDREQ ri = 29037 ai = 127
ISDN BR0: RX <- IDASSN ri = 29037 ai = 86
ISDN BR0: TX -> SABMEp sapi = 0 tei = 86
ISDN BR0: RX <- UAf sapi = 0 tei = 86
ISDN BR0: TX -> INFOc sapi = 0 tei = 86 ns = 0 nr = 0 i = 0x08007B3A0A30383335383636343031
ISDN BR0: RX <- INFOc sapi = 0 tei = 86 ns = 0 nr = 1 i = 0x08007B080382E43A
ISDN BR0: TX -> RRr sapi = 0 tei = 86 nr = 1
Layer 3 Troubleshooting with Cisco routers
One of the most important Cisco tools for debugging ISDN layer 3 problems is:
“debug isdn q931”
As with any use of debug, be careful when using it on a production router.
When you are interconnecting two routers through the Simulator, you might encounter problems because the
called router is not congured correctly.
See Figure 15 for a representative “debug isdn q931” output associated with a failed call. The call is initiated
by the ping to the remote router.
Figure 15: Layer 3 failure due to called router misconguration.
router#debug isdn q931
ISDN Q931 packets debugging is on
router#ping 192.168.0.1
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echoes to 192.168.0.1, timeout is 2 seconds:
ISDN BR0: TX -> SETUP pd = 8 callref = 0x10
Bearer Capability i = 0x8890
Channel ID i = 0x83
Called Party Number i = 0x80, ‘8358661
ISDN BR0: RX <- RELEASE_COMP pd = 8 callref = 0x90
Cause i = 0x82EF - Protocol error, unspecied
ISDN BR0: Event: incoming ces value = 1.
22
User Manual User Manual