Console Output and Serial Terminals

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Overview

This page describes different methods for setting up a serial console post booting up an NST system. See Getting Started - Server Boot for setting up a serial console initially during a NST Live boot.

Serial Console On NST 2.13.0

Use the following command to manually enable the serial console on NST versions 2.13.0 using upstart. This example will set the serial baud rate to: "57600" and use serial device: "/dev/ttyS0".

[root@probe ~]# initctl emit --no-wait fedora.serial-console-available ttyS0 57600
[root@probe ~]# 

Serial Console On NST 2.15.0 or Above

Use the following command to manually enable the serial console on NST versions 2.15.x or above using systemd. This example will use the current baud rate (agetty -s option) set typically during a boot time and use serial device: "/dev/ttyS0". If one needs to adjust the baud rate, send a break character on your communications application to cycle through the baud rate list (i.e., In this example: 115200, 38400 and 9600).

[root@probe ~]# systemctl start serial-getty@ttyS0.service
[root@probe ~]# 

To get the serial console status use the systemctl command as follows:

[root@probe ~]# systemctl status serial-getty@ttyS0.service
serial-getty@ttyS0.service - Serial Getty on ttyS0
          Loaded: loaded (/lib/systemd/system/serial-getty@.service)
          Active: active (running) since Tue, 17 May 2011 16:59:56 -0400; 5min ago
        Main PID: 31524 (agetty)
          CGroup: name=systemd:/system/serial-getty@.service/ttyS0
                  └ 31524 /sbin/agetty -s ttyS0 115200 38400 9600
[root@probe ~]# 

Add Additional Serial Login Devices

One can add additional Serial user login sessions on a device. If your NST system does not have a physical serial port, you can add a USB To Serial Converter for user login. In this example we add a USB To Serial Converter which attaches as device: "ttyUSB0". Simply start a serial login on this device as follows:

[root@probe ~]# systemctl start serial-getty@ttyUSB0.service
[root@probe ~]# 

To get the serial console status for this device use the systemctl command as follows:

[root@probe ~]# systemctl status serial-getty@ttyS0.service
serial-getty@ttyUSB0.service - Serial Getty on ttyUSB0
	  Loaded: loaded (/lib/systemd/system/serial-getty@.service)
	  Active: active (running) since Fri, 20 May 2011 08:42:06 -0400; 2min 3s ago
	Main PID: 1426 (login)
	  CGroup: name=systemd:/system/serial-getty@.service/ttyUSB0
[root@probe ~]#