Setting Up Modems

SETTING UPA DIAL UP MODEM ON REDHAT LINUX

USING KDE’S KPPP UTILITY TO CONFIGURE AN EXTERNAL MODEM Once X-Windows is up and running on any Linux box, access to a host of GUI based tools is available. KPPP, is KDE’s GUI based modem configuration utility. This utility is installed in the /usr/sbin/kppp sub directory on the Linux box.

Note Files stored within the sbin sub directory on a Linux computer are generally accessible to the root user. Hence login as root or alternatively su to root from any user login. The system prompt will be a # indicating that the Linux has recognized the root login or will change to a # indicating that Linux has recognized the conversion to root from another user login. # cd /usr/sbin ↵ # kppp ↵ To run KDE’s KPPP utility from within the sbin sub directory.

Note Alternatively, add a shortcut on the desktop to run KPPP, or add a menu item in the Start Menu to run KPPP, if access to this utility is not already available in the Start Menu. As soon as KPPP runs the screen as shown in diagram 1 is displayed.

Diagram 1

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The KPPP window that appears on the VDU screen has four buttons, they are: Quit, Setup, Help and Connect as shown in diagram 2.

Diagram 2

Note Assuming this is the first time that KPPP is run, there is no connection configured and hence the Connect button is disabled. Additionally, the KPPP window also displays three textboxes they are: Connect To, Login Id, Password as shown in diagram 3.

Diagram 3

Note Notice that the Connect to: is a drop down list box. This indicates that multiple connections to ISP’s can be configured and the appropriate one selected from the list displayed to connect to.

Since this is the first time that KPPP is being run click on window as shown in diagram 1.

button in the KPPP

This will open another window as shown in diagram 4 that will permit the capture of user data via tabbed pages in the KPPP setup screen. This setup screen really has two individual sets of tabbed pages accessed and used as described later in this material. One set of pages permits the capture of user data bound to the device being used, which port its connected to (i.e. Serial or USB), the speed of data transfer via the modem and so on. The other set of pages permits the capture of user data bound to the ISP connection, such as a Connection name, Telephone number to be dialed (multiple connection names and numbers can be specified and so on. Page

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SETTING UPA DIAL UP MODEM ON REDHAT LINUX

Diagram 4

Diagram 6

This is the KPPP Configuration screen that opens up when the Setup button is clicked. To setup an Account, Click New.

The New Account window opens as shown in Diagram 6. Enter a Connection Name. Here VSNL is chosen as the account name. Click Add to add a telephone number to dial. Another window opens to capture the telephone number to dial. See diagram 7.

Diagram 5 The Create New Account Screen appears as shown in diagram 5. This screen offers to assist in setting up the modem using a Wizard or through various dialog screens via the Dialog Setup command button. Ensure that the button is clicked. Do not opt to use the Wizard. Once Dialog Setup is chosen, the KPPP Configuration window will open immediately as shown in diagram 6. Via this window manual configuration of the Modem can begin.

Diagram 7 Enter the phone no. Click OK. The telephone number is transferred to the New Account window as in diagram 5. Do Not Click OK in the New Account window until the configuration is complete. Click the IP tabbed page, to setup the computers IP addressing as shown in diagram 8.

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Diagram 8

Diagram 10

The ISP normally sets the IP for the computer dynamically when the computer successfully logs in. In Configuration click the Dynamic IP address radio button. This is the default setting anyway.

Select the Device page. From the Modem device: drop down list box select the Serial or USB port that the modem is connected to. If the port is Com 1 then select: /dev/ttyS0 (Capital S followed by Zero).

Flow Control: Hardware [CRTSCTS]. Line Termination: LF Connection Speed: 57600 Modem timeout: 60 sec Tweak these setting if required, to map correctly to the modem being installed. Click the Modem tab. The screen as shown in diagram 10 appears.

Diagram 9 Since the computer is dialing to a specific ISP it must connect to the ISP’s default gateway server. In Configuration, click the Default gateway radio button. This is the default setting anyway. Now Click OK.

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This will permit setting up a few parameters for the Modem and testing whether the local link between the computer and the modem is working successfully or not. If the test is unsuccessful then check the Serial port to which the modem is connected, try changing the device file to another tty, perhaps ttyS1

SETTING UPA DIAL UP MODEM ON REDHAT LINUX

Diagram 11

Diagram 13

Select the Modem page. Switch off the Wait of dial tone before dialing check box. Set the Modem Volume to midway. Click Query Modem.

If all the parameters have been passed correctly, the output of the computer querying the modem will be displayed as shown in diagram 13. This means a successful link was established between the computer on its serial port and the Modem. Assuming that the Modem query check went through OK then its time to finally click OK on the KPPP configure screen. This exits to the dial up screen.

Diagram 12 Immediately the computer begins to query the Modem as shown in diagram 12.

Here pass the Login Id and Password provided by the ISP before actually dialing in to the ISP of choice. This is shown in diagram 14.

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Diagram 14

Diagram 16

Enter the Login ID and Password and then click Connect.

Once the Modem connects to the ISP’s network the gateway to browse the Internet is open and ready.

If each command sent to the Modem from the computer needs to be seen, Click the Show log window, check box On. The Modem will dial in to the ISP using the telephone line that it is connected to as shown in diagram 15.

The current window (i.e. Connecting to VSNL) will immediately minimize to the Status bar of the Linux desktop. Invoke an Internet browser, such as Mozilla or Konqueror, or any other Linux browser of choice, type in a URL to navigate to and everything should work just fine. Right click the minimized Connect window in the status bar to view the KPPP statistics if required. Please see diagram 17.

Diagram 15 Once a connection is established between the Modem and the ISP it will attempt to connect to the ISP’s network as shown in diagram 16.

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SETTING UPA DIAL UP MODEM ON REDHAT LINUX

Diagram 17. The Modem is setup and running just fine as can be seen from diagram 16. Close the KPPP statistics window and continue browsing. To disconnect, Click on the VSNL window visible in the status bar and select disconnect.

Error Handling If errors are displayed at the time when the Modem was queried then carefully navigate through each screen once again and check the parameters passed in earlier. If an error is noticed, correct this and try again. Common errors, Modem port configured wrong. A Serial port chosen for a USB modem and vice versa. The wrong Serial or USB device driver identity used. Serial Port Com1 Com2 Com3 Com4

Identities /dev/ttyS0 /dev/ttyS1 /dev/ttyS2 /dev/ttyS3

USB Port Identities USB1 USB2 USB3 USB4

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THE RELIANCE FIXED LINE PHONE WORKING UNDER REDHAT 9.0 To get the Reliance Fixed line phone to work under RedHat Linux first down load the appropriate driver software from the following URL: http://www.relianceinfo.com/Infocomm/html/rservices/rservices_linux_rconnect.html The name of the tarball used for installing this software is: rconnect-cmdln-0.5.tar The web site indicates that it’s tested on RedHat 8 and SuSE, but seems to work fairly well on RedHat 9 as well. This really means that we’ve did encounter any problems when trying to install this driver on RedHat 9. We hope you have the very same experience.

Note Remember to activate the Reliance Internet account in the normal way. Only after a confirmatory SMS is received indicating that the Internet account has been activated attempt to use the Reliance Internet gateway. Once the tarball is downloaded, copy it to a subdirectory to begin the Install process. Login as root. Create a sub directory under /. eg. /relphone # mkdir /relphone ↵ Copy the downloaded tarball to this sub directory. Change to that sub directory to begin the installation process. # cd /relphone ↵ Extract the contents of the tarball by issuing the following command. # tar –xvzf rconnect-cmdln-0.5.tar ↵ The contents of the tar ball are extracted into the sub directory rconnect-0.5 under the /relphone directory. (See diagram 1)

Diagram 1 Page

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SETTING UPA DIAL UP MODEM ON REDHAT LINUX

Change to this sub directory. # cd rconnect-0.5 (Notice there is no slash before the directory name) To start the installation process, do the following: # ./rconnect ↵ The screen as shown in diagram 2 will be seen. The model of the fixed line phone used was LG LSP – 340E, hence the number 3 was entered at the prompt. Press Enter. See diagram 3.

Diagram 2

Diagram 3 On pressing Enter, the Serial port device driver name is asked for by the install process. On our computer the Serial port used was Com1 hence the device driver was passed as /dev/ttyS0. See diagram 4.

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Diagram 4 Press Enter. The installation process will indicate that its searching on the Serial port indicated for the telephone. Within a few seconds installation process indicates that the phone was found and that the installation was completed successfully. See diagram 5.

Diagram 5 The system prompt is displayed once again.

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SETTING UPA DIAL UP MODEM ON REDHAT LINUX

To login into the Internet using the Reliance gateway at the system prompt issue the following command: # rconnect <Password> ↵

Note The Login ID and Password for the Reliance Internet gateway is the user’s area code followed by the telephone number. Assuming a Mumbai user then an example will be: 2230907863. Hence an example of the command to log into the Internet using the Reliance Internet gateway will be as follows: # rconnect 2230907805 2230907805 ↵

(See diagram 6)

Diagram 6 Immediately look at the display on the telephone, it will change to the Modem display. Indicating that the fixed line phone in now operating as a modem. On successful login to the Internet the system prompt will be returned. # You are now successfully logged into the Internet using the Reliance Internet Gateway. Open up a web browser such as Mozilla or Konqueror, or any other Linux browser of choice, type in a URL to navigate to and everything should work just fine.

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To disconnect from the Internet at the system prompt issue the command: # rdisconnect ↵ The system prompt will be returned almost immediately. Look at the display on the telephone it will have changed to the normal telephone display indicating that the fixed line phone in now operating as a normal phone. See diagram 7.

Diagram 7

CONFIGURING A MODEM USING ONLY A TEXT EDITOR Having had a look at how the RedHat 9.0 GUI based tool can be used to setup and configure a Modem its time to understand how to setup and configure a Modem using only a text editor. This is because when RedHat is installed as a dedicated Server or Enterprise Server, its GUI tools are not loaded nor is X-Windows software loaded and run on the server. This is because X-Windows itself runs as a Server process and has its own unique listening port, which is always open. This port cannot ever be closed, as soon as the listening port is closed X-Windows simply stops working. As long as there is a public port open and active on a Server, (i.e. cannot be protected) the Server is vulnerable and via the Server all the clients connected to it are vulnerable as well. Clever system hackers know which port X-Windows opens and listens on. Actually the port number is in the open domain. It is possible to make use of this knowledge to cleverly insert malicious code onto the Linux box. Once this kind of malicious code is installed and can be called remotely all the Server resources are at serious risk. A simple way around this issue is to install all the GUI based Server configuration tools on a client computer connected to the Linux Server. The GUI based Server tools an this client can then be used to telnet to the Master Server and maintain it. After all the necessary maintenance and configuring is complete, the telnet link between the client and the Server can be safely broken. The X-Windows server software now running on the client can be exited as soon as all the Master Server work is complete. Page

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SETTING UPA DIAL UP MODEM ON REDHAT LINUX

Inspite of this, its always a good idea to be able to handle as much of the necessary Server side configuration and maintenance from the command prompt rather than using X-Windows and the Linux GUI. When RedHat Linux was installed an executable called wvdialconf was installed in /etc. This file can be run from the system prompt by typing in wvdialconf and pressing Enter. Log in as root, or su to root. # wvdialconf ↵ This executable scans all the Serial ports and makes appropriate entries into the wvdial.conf file. The wvdial.conf file is located in ********** Once wvdialconf has been run on the computer as shown above, some of entries in the file have to be edited and if really necessary some entries need to be freshly made. For each Serial port identified on the computer there will be an appropriate entry made in the wvdial.conf file. In each of these blocks of entries a minimum of three parameters must be edited if the Modem is to work correctly. They are: Parameter phone username password

What’s to be entered <Enter the ISP’s telephone number here> <Enter the username provided to (or by) the ISP here> <Enter the password provided to (or by) the ISP here>

It is obvious that the executable wvdialconf cannot make these entries automatically. After a successful log in to an ISP’s Internet Gateway Server via the dial-up modem, a web browser (i.e. Mozilla or Konqueror or any other Linux compatible browser) must be invoked to actually surf the Internet and navigate to the specific URL’s keyed into its Address or Location bar. The web browser needs to know the IP address of the Internet Gateway Server to whom it must address all the client calls to navigate a specific domain name especially for domain name to IP resolution. The IP address of the ISP’s Internet Gateway Server must be made in the resolv.conf file. This file is in the /etc folder. The following entries are made in the resolv.conf file: Parameter search nameserver nameserver

What’s to be entered dns.vsnl.net.in 202.54.1.30 202.54.1.18

Once these entries are made everything is ready to log in to the Internet using the Linux box.

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Logging In To The Internet # wvdial

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