Windows NT RAS Scripting

Microsoft's Remote Access Services (RAS) is a powerful connectivity tool for wide-area connections for numerous applications, including remote connectivity to a Windows NT Server and connectivity from a Windows NT Workstation or Server system to the Internet, CompuServe, and other online systems. Unfortunately, RAS has little integrated support for non-Microsoft connections. For example, if you use the standard RAS setup to dial in to the Internet or CompuServe, you have to invoke the RAS Terminal interface to manually log in to the service. Fortunately, Microsoft lets you automate this process. To automate logins, you can create scripts and store them in the switch.inf file. This text file is in the %SYSTEMROOT%\SYSTEM32\RAS directory (%SYSTEMROOT% is the drive and topmost directory for your Windows NT software; e.g., C:\WINNT35.

Because the default switch.inf file contains several explanations, suggestions, and examples, get acquainted with this file before you start editing it. Also, back up the file before you start altering it.

<cr>	Carriage return
<lf>	Line feed
<match>"abcdef"	Waits for match to "abcdef"
<ignore>	Ignores the rest of the response
<?>	Wildcard character
<hNN>	Used to represent a hexadecimal value containing the digits NN
<diagnostics>	Displays a diagnostic message box
OK=value	Defines the expected response
COMMAND=value<cr>	Sends the text string "value"
NoResponse	No response is expected
CONNECT=value	Terminates the script when the "value" is received
ERROR_NO_CARRIER=value	Checks for the loss of the modem carrier
ERROR_DIAGNOSTICS=value	Checks for diagnostic messages
LOOP=value	Loop waiting for a match value

To create a new script, you define a section header (a title) for it. The section header can be anything--it is only a configuration item in your RAS phone book entry. Then you need to know exactly what the connecting network expects to send and receive during the login process. To get this information, use the RAS Terminal interface, turn on screen capture, and complete the login process manually. You can then develop an automated script from the information you record in the capture file.

RAS Scripts
Each script starts with a section header and then has command and response entries. Table 1 lists and explains the various commands. To document the script, you can add comments, which start with a semicolon.

Below is a typical RAS login script. For this script to work, you must replace the strings myusername and mypassword with a valid username and password.

[Xylogics Annex Three]

; Wait until you get the "USERNAME:" prompt

COMMAND=

ERROR_NO_CARRIER=<match>"NO CARRIER"

OK=<match>"AME:"

; Send the USERNAME

COMMAND=MYUSERNAME<cr>

ERROR_NO_CARRIER=<match>"NO CARRIER"

;wait for "PASSWORD:" prompt

OK=<match>"ORD:"

; Send the PASSWORD and ignore response

COMMAND=MYPASSWORD<cr>

ERROR_NO_CARRIER=<match>"NO CARRIER"

; Wait for "Annex>" send the PPP command

OK=<match>"nnex>"

COMMAND=PPP<cr>

ERROR_NO_CARRIER=<match>"NO CARRIER"

; Wait for the Annex to start up PPP mode

CONNECT=<match>"Switching to PPP"

ERROR_DIAGNOSTICS=<cr><lf><Diagnostics>

ERROR_DIAGNOSTICS=<lf><cr><lf><Diagnostics>

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