System information

CHAPTER

Troubleshooting Dialin Connections 16-343

Troubleshooting Dialin Connections

This chapter describes procedures for troubleshooting dialin connections. The chapter begins with

the following sections:

• Using the modem autoconﬁgure Command

• Establishing a Reverse Telnet Session to a Modem

• Interpreting show line Output

The remainder of the chapter presents symptoms, problems, and solutions for router-to-router and

PC-to-router dialin connections:

• Dialin: No Connectivity Between Modem and Router

• Dialin: Modem Does Not Dial

• Dialin: Modem Does Not Answer

• Dialin: Modem Hangs Up Shortly After Connecting

• Dialin: Dialin Client Receives No exec Prompt

• Dialin: Dialin Session Sees “Garbage”

• Dialin: Dialin Session Ends Up in Existing Session

• Dialin: Modem Cannot Send or Receive Data

• Dialin: Modem Cannot Send or Receive IP Data

• Dialin: Modem Cannot Send or Receive IPX Data

• Dialin: Modem Does Not Disconnect Properly

• Dialin: Link Goes Down Too Soon

• Dialin: Link Does Not Go Down or Stays Up Too Long

• Dialin: Poor Performance

Note This chapter does not cover Apple Remote Access (ARA) dialin connections. For information

on troubleshooting ARA connections, see Chapter 9, “Troubleshooting AppleTalk.”

Using the modem autoconﬁgure Command

If you are using Cisco Internetwork Operating System (Cisco IOS) Release 11.1 or later, you can

conﬁgure your Cisco router to communicate with and conﬁgure your modem automatically.