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>1.1. What is a console?</H1
><P
>The console is the text output device for system
administration messages. These messages come from the kernel, from
the <SPAN
CLASS="APPLICATION"
>init</SPAN
> system and from the system
logger.</P
><P
>On modern small computers the console is usually the
computer's attached monitor and keyboard.</P
><P
>On many older computers the console is an
<SPAN
CLASS="ACRONYM"
>RS-232</SPAN
> link to a terminal such as a
<SPAN
CLASS="ACRONYM"
>DEC</SPAN
>
<SPAN
CLASS="PRODUCTNAME"
><SPAN
CLASS="ACRONYM"
>VT100</SPAN
></SPAN
>. This terminal
is in a locked room and is continually observed by the
minicomputer's operators. Large systems from Sun, Hewlett-Packard
and <SPAN
CLASS="ACRONYM"
>IBM</SPAN
> still use serial consoles.</P
><P
>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 <SPAN
CLASS="SYSTEMITEM"
>root</SPAN
> super-user from the console is
the Command Line of Last Resort when faced with a misbehaving
system.</P
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