3Com Router User Manual

Troubleshooting DCC747
Use the DCC Debugging 
Information to Locate 
ProblemsEnabling DCC debugging
Execute the following commands in system view for displaying the DCC 
debugging information:
[Router] debugging dialer event
[Router] debugging dialer packet
[Router] info-center enable
Output debugging information for the interconnection failure between 
DCC and the remote end and diagnosis 
In this section, the debugging information that may be output when DCC cannot 
reach the remote end will be...

748CHAPTER 51: CONFIGURING DCC
DCC: peeraddr matching  error 
on interface ***, shutdown linkThe debugging information is probably outputted 
because the local dialer route does not contain the 
remote network address. To solve the problem, add 
the dialer route corresponding to the remote 
network address on the local router or use the dial 
number after removing all the dialer routes 
configured on the local router.
DCC: idle-timeout on interface 
*** , shutdown! start 
enable-timeThe debugging...

52
CONFIGURING MODEM 
This chapter covers the following topics:
■Modem Function Provided by 3Com Routers
■Configuring a Modem
■Displaying and Debugging a Modem
■Modem Configuration Examples
■Troubleshooting
Modem Function 
Provided by 3Com 
RoutersTo offer the optimal flexibility, 3Com routers provide the following modem 
management functions:
■Provide the scripts (modem script) for modem management to enable the user 
to better control the modems connected to the router. A modem script can be 
executed...

750CHAPTER 52: CONFIGURING MODEM
Syntax description of modem script 
The modem script format in common use is as follow:
receive-string1 send-string1 receive-string2 send-string2......
Where:
■Normally, receive-string and send-string appear in pairs, and the script must 
begin with a receive-string. For example, “receive-string1 send-string1” 
represents the execution flow: Expect to receive receive-string1, and send 
send-string1 to the modem if the received string matches receive-string1 
before timing...

Configuring a Modem751
Ta b l e 775   Script Keywords
In which, seconds defaults to 180 and is in the range of 0 to 180.
Ta b l e 776   Script Escape Characters
Configuring a ModemModem Configuration includes:
■Configure the Modem Dial-in and Dial-out Authorities
■Configure Modem Through the AT Command
■Configure a Modem Script
■Execute a Modem Script Manually
■Specify the Events that Trigger Modem Scripts
■Configure the modem-related operation mode for the asynchronous interface
■Configure the Modem...

752CHAPTER 52: CONFIGURING MODEM
Configure Modem 
Through the AT 
CommandPerform the following configuration in interface (asynchronous serial, AUX or AM 
interface) view.
Ta b l e 778   Configure a Modem Script
A modem can accept the AT commands only when it is in AT command mode. If it 
is forwarding data, the AT command sent via the 
sendat at-string command is 
invalid.
Configure a Modem 
ScriptPerform the following configuration in system view.
Ta b l e 779   Configure a Modem Script
For the format...

Configuring a Modem753
Perform the following configuration in interface (asynchronous serial, AUX or AM 
interface) view.
Ta b l e 781   Specify the Events Triggering the Modem Scripts
The argument following the script init-string command is the initialization 
string rather than the modem script name. 
Configure the Modem 
Answer Mod
e
This configuration depends on whether the external modem to which the 
asynchronous interface is connected is in auto-answer mode (whether the AA LED 
on the modem is...

754CHAPTER 52: CONFIGURING MODEM
Ta b l e 783   Configure Authentication for Modem Dial-In User
By default, the authentication for a modem dial-in user is not configured.
Displaying and 
Debugging a ModemExecutethe debugging command in all views for the debugging.
Ta b l e 784   Display and Debug Modem
Modem Configuration 
ExamplesThis section provides the following examples:
■Managing a Modem Through a Modem Script
■Power-on Initialization through the Initialization Script
■Use the Script to Dial...

Modem Configuration Examples755
Restore the ex-factory modem settings
To restore the ex-factory modem settings, use the “AT&F” command.
[Router]script-string factory  AT OK AT&F OK
[Router]interface serial 0
[Router-Serial0]start-chat factory
Configure the modem initialization parameters
Correctly initializing the modem configuration is an important step for the correct 
connection with the modem. The following contents briefly introduce the 
conventional AT initialization commands and the works for...

756CHAPTER 52: CONFIGURING MODEM
Power-on Initialization 
through the 
Initialization ScriptEnable the router to initialize the modem to which the asynchronous interface is 
connected when powering on the router or rebooting it.
[Router] script-string init  AT OK AT&B1&C1&D2&S0=1 OK AT&W OK
[Router] interface async 0
[Router-Async0] modem
[Router-Async0] start-chat init
Use the Script to Dial 
DirectlyConfigure a modem script and direct dial.
[Router] script-string dial  AT OK ATDT8810058 CONNECT...