1.1. What is a console?
The console is the text output device for system
administration messages. These messages come from the kernel, from
the init system and from the system
logger.
On modern small computers the console is usually the
computer's attached monitor and keyboard.
On many older computers the console is an
RS-232 link to a terminal such as a
DEC
VT100. This terminal
is in a locked room and is continually observed by the
minicomputer's operators. Large systems from Sun, Hewlett-Packard
and IBM still use serial consoles.
It is usually possible to login from the console. A login
session from the console is treated by many parts of the operating
system as being more trustworthy than a login session from other
sources. Logging in as the root super-user from the console is
the Command Line of Last Resort when faced with a misbehaving
system.