Fault Diagnosis and Troubleshooting of LAPB
241
[Router-x25-profile1]
x25 vc-range in-channel 10 20 bi-channel 30
1024
[Router-x25-profile1]
x25 pvc 1 interface serial 0 pvc 1
5
Configure Serial 1.
a
Configure S1 as the Frame Relay interface.
[Router]
interface serial 1
[Router-Serial1]
link-protocol frame-relay
b
Configure a Frame Relay Annex G DLCI.
[Router-Serial1]
fr dlci 100
[Router-fr-dlci-100]
annexg dte
c
Apply the X.25 template to Annex G DLCI 100 (which is equivalent to
configure X.25 attributes for the Annex G DLCI).
[Router-fr-dlci-100]
x25-template profile1
Fault Diagnosis and
Troubleshooting of
LAPB
Fault 1: Two connected sides use X.25 link layer protocol (or LAPB), but the
protocol is always disconnected. Turn on the debugging switch. It is found
that one end sends SABM frame, while the other end sends FRMR frame
circularly.
Troubleshooting: this is because both sides worked in the same working mode
(DTE or DCE). Change the working mode of one side to solve the problem.
Fault 2: Two connected sides use X.25 link layer protocol, and the protocol
is already in UP status, but cannot ping through the peer. Turn on the
debugging switch and it is found that the received frames are discarded
on one end instead of being forwarded up to the packet layer.
Troubleshooting: The maximum frame bits of this end may be too small. Change
the configuration.
Fault Diagnosis and
Troubleshooting of
X.25
This section describes some common faults and the troubleshooting methods.
Assuming that the connection of the X.25 layer 2 (LAPB) is completely correct.
Fault 1: LAPB is already in "Connect" status, but the X.25 protocol can not
enter "UP" status.
Troubleshooting: It is possible that the local working mode has been configured
wrong, for example, both sides of a connection are DTE or DCE. Try again after
changing the interface working mode.
Fault 2: X.25 protocol is "UP", but virtual circuit can not be established, i.e.,
unable to ping through.
This may be caused by one of the following:
■
Local X.121 address not configured
■
Address mapping to the peer not configured
■
Opposite X.121 address not configured
■
Address mapping from peer to local not configured
■
Channel range not correct
Summary of Contents for 3036
Page 1: ...http www 3com com 3Com Router Configuration Guide Published March 2004 Part No 10014299 ...
Page 4: ...VPN 615 RELIABILITY 665 QOS 681 DIAL UP 721 ...
Page 6: ...2 ABOUT THIS GUIDE ...
Page 7: ...I GETTING STARTED Chapter 1 3Com Router Introduction Chapter 2 3Com Router User Interface ...
Page 8: ...4 ...
Page 16: ...12 CHAPTER 1 3COM ROUTER INTRODUCTION ...
Page 34: ...30 ...
Page 60: ...56 CHAPTER 3 SYSTEM MANAGEMENT ...
Page 98: ...94 CHAPTER 6 DISPLAY AND DEBUGGING TOOLS ...
Page 110: ...106 ...
Page 114: ...110 CHAPTER 8 INTERFACE CONFIGURATION OVERVIEW ...
Page 158: ...154 CHAPTER 10 CONFIGURING WAN INTERFACE ...
Page 168: ...164 ...
Page 188: ...184 CHAPTER 13 CONFIGURING PPPOE CLIENT ...
Page 192: ...188 CHAPTER 14 CONFIGURING SLIP Router ip route static 0 0 0 0 0 0 0 0 10 110 0 1 ...
Page 248: ...244 CHAPTER 16 CONFIGURING LAPB AND X 25 ...
Page 320: ...316 ...
Page 330: ...326 CHAPTER 20 CONFIGURING IP ADDRESS ...
Page 362: ...358 CHAPTER 21 CONFIGURING IP APPLICATION ...
Page 374: ...370 CHAPTER 23 CONFIGURING IP COUNT ...
Page 406: ...402 CHAPTER 25 CONFIGURING DLSW ...
Page 408: ...404 ...
Page 452: ...448 CHAPTER 29 CONFIGURING OSPF ...
Page 482: ...478 CHAPTER 30 CONFIGURING BGP ...
Page 494: ...490 CHAPTER 31 CONFIGURING IP ROUTING POLICY ...
Page 502: ...498 ...
Page 508: ...504 CHAPTER 33 IP MULTICAST ...
Page 514: ...510 CHAPTER 34 CONFIGURING IGMP ...
Page 526: ...522 CHAPTER 36 CONFIGURING PIM SM ...
Page 528: ...524 ...
Page 532: ...528 CHAPTER 37 CONFIGURING TERMINAL ACCESS SECURITY ...
Page 550: ...546 CHAPTER 38 CONFIGURING AAA AND RADIUS PROTOCOL ...
Page 590: ...586 CHAPTER 40 CONFIGURING IPSEC ...
Page 599: ...IX VPN Chapter 42 Configuring VPN Chapter 43 Configuring L2TP Chapter 44 Configuring GRE ...
Page 600: ...596 ...
Page 638: ...634 CHAPTER 43 CONFIGURING L2TP ...
Page 649: ...X RELIABILITY Chapter 45 Configuring a Standby Center Chapter 46 Configuring VRRP ...
Page 650: ...646 ...
Page 666: ...662 ...
Page 670: ...666 CHAPTER 47 QOS OVERVIEW ...
Page 700: ...696 CHAPTER 49 CONGESTION MANAGEMENT ...
Page 706: ...702 CHAPTER 50 CONGESTION AVOIDANCE ...
Page 707: ...XII DIAL UP Chapter 51 Configuring DCC Chapter 52 Configuring Modem ...
Page 708: ...704 ...
Page 762: ...758 CHAPTER 52 CONFIGURING MODEM ...