8.3. Test the console

Dial in from a machine, perhaps using Minicom.

Example 8-1. Dialing into a serial console

localhost bash$ minicom

Initializing modem
Welcome to minicom 1.83.1
Press ALT-Z for help on special keys
AT S7=45 S0=0 L1 V1 X4 &C1 E1 Q0                     
OK
Alt-D remote.example.edu.au-ttyS0
Dialing: remote.example.edu.au-ttyS0 At: 1234-5678
Connected. Press any key to continue
Any
CONNECT 115200/V34/LAPM/V42BIS/33600:TX/33600:RX

Enter
/etc/issue says "All your base are belong to us".
remote.example.edu.au ttyS0 login: user
Password: ********
Message of the day is "be careful out there".
remote bash$ stty -a
speed 9600 baud; rows 0; columns 0; line = 0;
intr = ^C; quit = ^\; erase = ^?; kill = ^U; eof = ^D; eol = <undef>;
eol2 = <undef>; start = ^Q; stop = ^S; susp = ^Z; rprnt = ^R; werase = ^W;
lnext = ^V; flush = ^O; min = 1; time = 0;
-parenb -parodd cs8 hupcl -cstopb cread -clocal crtscts
-ignbrk brkint ignpar -parmrk -inpck -istrip -inlcr -igncr icrnl -ixon -ixoff
-iuclc -ixany -imaxbel
opost -olcuc -ocrnl onlcr -onocr -onlret -ofill -ofdel nl0 cr0 tab3 bs0 vt0 ff0
isig icanon -iexten echo echoe echok -echonl -noflsh -xcase -tostop -echoprt
-echoctl -echoke
…
remote bash$ logout

NO CARRIER
Alt-X
Leave Minicom? Yes
Resetting modem

localhost bash$

Interestingly the stty -a command, used to display the terminal settings, reports that the link from the modem to the serial console is 9600bps. The CONNECT message reports that link between the two modems operates at 33600bps. The constant speed modem-computer link is a very useful feature of the Hayes AT-style modems: the calling computer need not know in advance the line speed of the called serial console.

HOWTOs

8.3. Test the console