Novell Documentation: GroupWise Gateway

Troubleshooting Modems

You can configure modems in different ways. There is no set method for solving your modem connection problems; however, there are some basic strategies you can follow and configuration changes you can try if your modem connection fails. Try using the following strategies in the order they are listed:

Make sure the modem initialization strings at both GroupWise sites are set for a fixed DTE rate. Check your modem documentation for more information.
Make sure flow control at the port definition and in the modem initialization string is set to CTS/RTS (hardware flow control). Check your modem documentation for initialization codes.
Disable data compression at both GroupWise sites. If you are using the Async Gateway, data compression should be disabled on the modems of the local and remote GroupWise domains. This is because the gateway compresses files before they are transferred to the modem. In many cases, if the modem attempts to compress a file that has been compressed, modem performance can be affected. See your modem documentation for more information about disabling data compression.
Lower the selected baud rate until the modems connect.
Create a new modem initialization string. For more information, see Creating a Modem Initialization String.
Use aioterm.nlm to troubleshoot Async NLM^TM program. For more information, see Using Aioterm.nlm to Troubleshoot the NetWare Async Gateway.
Send a test message to check links and connections to certain domains. For more information, see Testing the Async Gateway.

Creating a Modem Initialization String

If previous troubleshooting efforts were unsuccessful, the modem initialization string you have used from the modem database might not be working. It might be necessary for you to create a new modem initialization string to check this possibility.

You need to know what to include in a new initialization string. See the manufacturer's modem operation manual under index entries such as "initialization string," "init string," or "AT string," or contact the modem manufacturer for more information about the initialization string.

The initialization string should include characters for the following:

Enable verbal result codes
Turn command echo off
Track data carrier
Return CONNECT messages
Drop carrier and reset modem when DTR drops
Enable error correction
Enable CTS/RTS
Set modem to fixed DTE speed

For complete instructions, see Creating a Modem Initialization String.

Using Aioterm.nlm to Troubleshoot the NetWare Async Gateway

Aioterm.nlm, available from Novell Support, can provide some data about the modem intialization string that you might find helpful in troubleshooting.

You should download a file called aiotrm.exe, which is a self-extracting, compressed file including the aioterm.nlm.

Load aioterm as you would any NLM. It displays the driver (or hardware) type, board number, and ports supported. After the initial loading sequence, the Acquired Port Test Menu is displayed. Follow these steps to obtain modem initialization string information in aioterm.nlm:

From the Acquired Port Test Menu, select Really Dumb Terminal Mode to display the following prompt:
```
Any keyboard activity will be written to the port, but not echoed to the screen. 
```
The screen shows only characters received from the port (if you don't see anything, try typing ATE1).
Type any character on the keyboard to activate the Really Dumb Terminal communications program.

The program communicates with the modem and has it send its initialization string. If the communication is working, the screen displays information something like this:
```
at
```
```
OK
```
```
at&v
```
```
Error
```
```
ati4
```
```
USRobotics Courier 16800 HST Dual Standard Settings
```
```
B0 C1 E1 F1
```
If there is no response from the modem, enter ATE1. If there is still no response from the modem, a problem with the serial expansion board or IO drivers is indicated.