This section describes how to install a modem onto a serial port. It describes how to set up the hardware and software to support a UUCP modem connection. (Refer to the Serial Device Manager in the System Manager for a GUI-based approach to the tasks discussed in this section.)
Topics in this section are
Silicon Graphics is compatible with most industry-standard modems. This section uses the US Robotics Sportster and Telebit modems as examples for the installation procedure. If you are using another type of modem, substitute its information where applicable.
You can use the standard system software to set up a modem for three different modes:
If you want to set up your modem for a SLIP or PPP connection, complete the modem configuration steps in the chapter and then refer to the SLIP or PPP configuration procedures in IRIX Admin: Networking and Mail.
There are a few prerequisites you should be aware of before installing the modem. Review the following points before installing the modem.
Table 1-1 shows the modem types and their configuration scripts.
versions | grep uucp
Check the versions output for the following line:
I eoe.sw.uucp uucp utilities
If the line above is not present, eoe.sw.uucp is not installed. See IRIX Admin: Software Installation and Licensing for instructions on installing a subsystem and install eoe.sw.uucp.
Warning:
Be sure you are not violating a site security policy by installing a modem on your system. If your system is networked to other systems, access to your system by modem provides a potential point of unauthorized access to the entire network.
The major tasks for setting up the modem software are similar, no matter how you choose to use your modem.
Table 1-2 provides an overview of the major tasks for each of the three usage modes. An "x" in the table denotes that the task is performed.
The installation procedure in this section is used to start the software setup for the three usage modes. Follow the procedure until you reach the section that is specific for the usage mode you have chosen. Then continue with that section. For example, if you are configuring your modem for dial-in only, complete the procedures in this section and the "Dial-In Mode" section.
Find the line for the port. The line begins with tportnumber, where portnumber is the number of a serial port. For example, if you connected your modem to port 2, look for a line similar to the following:
t2:23:respawn:/etc/getty -N ttyd2 co_9600 #port 2
Change respawn to off. This tells the system not to restart the /etc/getty program when it exits. If it is already off, continue to the next step. The line should look like this when you are finished:
t2:23:
off:/etc/getty -N ttyd2 co_9600 #port 2
telinit q
| Dial-In | Dial-Out | Dial-In/Dial-Out |
|---|---|---|
| -i | -o | -io |
Note: Be sure to view the entire configuration script for information and command arguments specific to your modem type before running the script.
For example, if you want to configure a US Robotics Sportster modem for dial-in/dial-out connected to port 2, use the fix-usr command and specify a dial-in/dial-out argument (-io) and the port number to which the modem is connected. For example, enter the command
/etc/uucp/fix-usr -io 2
You can also specify the optional modem model type and the modem speed using the command
/etc/uucp/fix-usr -io -m SPORT -s 38400 2
As another example, to configure a Telebit modem for dial-in only mode, use the fix-telebit command and specify a dial-in modem (-i), the model of the modem (tb+, t1000, t1600, t2500) and its speed, and the port number to which the modem is connected.
In this example, if a T2500 modem is connected to port 2 at 19,200 baud, dial-in only, enter the following command:
/etc/uucp/fix-telebit -i -m t2500 -s 19200 2
This section describes additional steps for configuring dial-out only and dial-in/dial-out modems. Be sure you have completed the steps in "Modem Software Setup, All Modes" before starting the setup in this section.
You turn on dial-out modem software by editing the /etc/uucp/Devices file. You also have to change ownership of the port to UUCP.
ACU ttynportnumber null baud 212 x dialer
Direct ttydportnumber - baud direct
The value for portnumber is the number of the serial port to which the modem is connected. The baud variable is the baud rate at which the modem runs. The dialer variable is the model tag, as listed in the first field of the /etc/uucp/Dialers file.
Note: If your modem type is not listed in the Dialers file, you may want to obtain the most up-to-date version of the Dialers file. It is available online from Silicon Graphics with the ftp utility.
For example, for a US Robotics modem connected to serial port 2 that can accept and send data at 38,400 baud (using RTS/CTS hardware flow control), add the following lines to the Devices file:
ACU ttyf2 null 38400 212 x usr
Direct ttyd2 - 38400 direct
Direct ttyf2 - 38400 direct
For a Telebit modem connected to serial port 2 and running at 19,200 baud, add the following lines:
ACU ttyf2 null 19200 212 x telebit
Direct ttyd2 - 19200 direct
Direct ttyf2 - 19200 direct
Save and exit the Devices file.
chown uucp /dev/tty[dfm]2
When you have finished the above process, try to dial out through the modem to verify the dial-out setup, as described in "Dialing Out to Another Modem". For more information on dialer options, see the file /etc/uucp/Dialers.
Be sure you have completed the steps in "Modem Software Setup, All Modes". For dial-in/dial-out mode, be sure you have also completed the steps in "Dial-Out Mode".
Complete the configuration by editing the file /etc/inittab. Perform the following steps:
Find the line for the port to which the modem is connected. The line begins with tportnumber, where portnumber is the number of a serial port. For example, if you connected your modem to port 2, look for a line similar to the following:
t2:23:off:/etc/getty -N ttyd2 co_9600 #port 2
Make the following changes to this line:
off to respawn.
ttyd2 to ttyf2.
co_9600 to dx_115200. (This is the serial port interface speed. It lets the modem answer and connect at the maximum and slower baud rates.) This should be the highest possible speed for the serial port that your system supports. Refer to your Owner's Guide for your serial port's maximum interface speed.
For example, if you connected a US Robotics modem to serial port 2, and found a line similar to this line in /etc/inittab
t2:23:off:/etc/getty -N ttyd2 co_9600 #port 2
you would change it to read
t2:23:
respawn:/usr/lib/uucp/uugetty -Nt60 -iusrin,conn ttyf2 dx_38400 #Modem 555-2345
If you are setting up a Telebit modem to serial port 2, and found a line similar to this one
t2:23:off:/etc/getty -N ttyd2 co_9600 #port 2
you would change it to read
t2:23:
respawn:/usr/lib/uucp/uugetty -Nt60 -itelebitin,conn ttyf2 dx_19200 #Modem 555-3456
telinit q
To test the dial-in setup, have someone try to dial in to the system through this modem.
To dial out through the modem to verify the dial-out setup, continue with the section "Dialing Out to Another Modem."
There is no standard way to configure the system to time out dial-in connections after a set amount of time. One way to accomplish this, however, is by using a shell for the dial-in account that supports time-outs after a specified period (for example, tcsh).
Warning: You should not change root's shell to /usr/bin/tcsh if /usr is a separate filesystem because it may not be mounted in single-user mode.
Note: The tcsh timeout does not work for dial-in connections that use PPP, SLIP, or UUCP.
Alternatively, you could write a script that determines the length of time a user is logged in and acts accordingly (refer to last(1), grep(1), and who(1) for more information).
The cu utility dials your modem. Before you attempt to dial out, make sure your local modem is connected to both your system and a working telephone line. Also, make sure the modem is turned on. The cu syntax to dial the number 1-800-555-1234 is
cu 18005551234
Refer to the cu(1C) reference page for complete information on cu. If everything is working, you should hear the modem dialing and after a short time you should see the following message on your console:
Connected
<Enter> once.
<Enter> key, the tilde key (~), a period (.), and the <Enter> key again.