Configuring a Dial-In Shell Server
A dial-in server lets you connect to a system via a modem and phone line, and obtain a shell prompt, from which you can issue commands and view output. Using a dial-in server is a great deal like using Telnet or a secure shell server, except that your connection to the server is via a phone line. The mgetty package provides a simple-to-use dial-in server.
Configuration
To configure mgetty to answer incoming modem calls, use your favorite text editor to find the following lines in the file /etc/inittab
:
# Example how to put a getty on a modem line # #T3:23:respawn:/sbin/mgetty -x0 -s 57600 ttyS3
Then, modify the last line by deleting the hash mark (#) and changing ttyS3
to modem
:
T3:23:respawn:/sbin/mgetty -x0 -s 57600 modem
Notice that the revised line invokes mgetty, not getty. The final argument specified on the added line assumes that your modem is configured as /dev/modem
. If your modem is configured as a different device, you must adjust the added line accordingly. The Chapter 11 described the use of modemtool to configure your modem; if you followed its instructions, /dev/modem
refers to your modem.
To cause your configuration change to take effect, you must reboot your system. Alternatively, you can cause the init process to re-examine the inittab
file. To do so, issue the following command:
/sbin/telinit q
The mgetty process should begin monitoring your modem, awaiting an incoming call.
Using the Dial-In Server
To use the dial-in server, ...
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