Linuxdoc Linux Questions
Click here to ask our community of linux experts!
Custom Search

6.2. Traditional getty

Traditional getty implementations include uugetty and getty_ps.

The traditional getty is listed in /etc/inittab with the name of a section in /etc/gettydefs to use for its configuration. Our example in Figure 6-3 used the section CON9600.

There is no CON9600 in the standard gettydefs. This is deliberate, as serial consoles sometimes require slight tweaking. Copy the DT9600 entry and use it as your model.

Figure 6-4. Define CON9600 in gettydefs

# Serial console 9600, 8, N, 1, CTS/RTS flow control
CON9600# B9600 CS8 -PARENB -ISTRIP CRTSCTS HUPCL # B9600 SANE CS8 -PARENB -ISTRIP CRTSCTS HUPCL #@S @L login: #CON9600

Separate each line with a blank line.

Each configuration line has the syntax:

Figure 6-5. Syntax of entries in /etc/gettydefs, in EBNF

<label><initial_flags> # <final_flags> #<login_prompt>#<next_label>

The <label> is referred to on the getty command line.

The <next_label> is the definition used if a RS-232 Break is sent. As the console is always 9600bps, this points back to the original label. See Section 9.9 if you ever intend to have more one line for CON9600 in gettydefs.

<initial_flags> are the serial line parameters used by getty. These are modeled on the stty(1) and termios(3) options and the full list varies depending upon your getty variant. The parameters in Figure 6-4 ensure that a line at 9600bps with eight data bits and no parity is configured.

<final_flags> are the serial line parameters set by getty before it calls login. You will usually want to set a 9600bps line, SANE terminal handling, eight data bits, no parity and to hang up the modem when the login session is finished.

The <login_prompt> for serial lines is traditionally the name of the machine, followed by the serial port, followed by login: and a space. The macro that inserts the name of the machine and the serial port varies, see the documentation for your getty.