283 lines
4.0 KiB
HTML
283 lines
4.0 KiB
HTML
<HTML
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><HEAD
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><TITLE
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>Create fallback position</TITLE
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><META
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NAME="GENERATOR"
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CONTENT="Modular DocBook HTML Stylesheet Version 1.7"><LINK
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REL="HOME"
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TITLE="Remote Serial Console HOWTO"
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HREF="index.html"><LINK
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REL="UP"
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TITLE="Preparation"
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HREF="preparation.html"><LINK
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REL="PREVIOUS"
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TITLE="Preparation"
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HREF="preparation.html"><LINK
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REL="NEXT"
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TITLE="Select a serial port "
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HREF="preparation-setport.html"></HEAD
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CLASS="SECTION"
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BGCOLOR="#FFFFFF"
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><TR
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><TH
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COLSPAN="3"
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ALIGN="center"
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>Remote Serial Console HOWTO</TH
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></TR
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><TR
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><TD
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WIDTH="10%"
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ALIGN="left"
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>Prev</A
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><TD
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WIDTH="80%"
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ALIGN="center"
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>Chapter 2. Preparation</TD
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><TD
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WIDTH="10%"
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ALIGN="right"
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VALIGN="bottom"
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><A
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>Next</A
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ALIGN="LEFT"
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WIDTH="100%"></DIV
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><DIV
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CLASS="SECTION"
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><H1
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CLASS="SECTION"
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><A
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NAME="PREPARATION-FALLBACK"
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></A
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>2.1. Create fallback position</H1
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><P
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>Good system administrators always have a viable fallback
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plan to cope with failures. A mistake configuring the serial
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console can make both the serial console and the attached monitor
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and keyboard unusable. A fallback plan is needed to retrieve
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console access.</P
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><P
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>Many <SPAN
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CLASS="SYSTEMITEM"
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>Linux</SPAN
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>
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distributions allow boot diskettes to be created. Writing a boot
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diskette before altering the console configuration results in a
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boot diskette that passes good parameters to the kernel rather than
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parameters that may contain an error.</P
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><P
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>Under <SPAN
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CLASS="PRODUCTNAME"
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>Red Hat Linux</SPAN
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> a boot
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diskette is created by determining the running kernel
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version</P
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><DIV
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CLASS="INFORMALFIGURE"
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><A
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NAME="PREPARATION-FALLBACK-KERNELVERSION"
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></A
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><P
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></P
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><TABLE
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BORDER="1"
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BGCOLOR="#E0E0E0"
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WIDTH="100%"
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><TR
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><TD
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><FONT
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COLOR="#000000"
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><PRE
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CLASS="SCREEN"
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><TT
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CLASS="PROMPT"
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>bash$</TT
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> <B
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CLASS="COMMAND"
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>uname -r</B
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>
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<TT
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CLASS="COMPUTEROUTPUT"
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>2.4.2-2</TT
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></PRE
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></FONT
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></TD
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></TR
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></TABLE
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><P
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></P
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></DIV
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><P
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>and then using that version to create the boot
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diskette</P
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><DIV
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CLASS="INFORMALFIGURE"
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><A
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NAME="PREPARATION-FALLBACK-RHLDISK"
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></A
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><P
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></P
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><TABLE
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BORDER="1"
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BGCOLOR="#E0E0E0"
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WIDTH="100%"
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><TR
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><TD
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><FONT
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COLOR="#000000"
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><PRE
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CLASS="SCREEN"
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><TT
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CLASS="PROMPT"
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>bash#</TT
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> <B
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CLASS="COMMAND"
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>mkbootdisk --device /dev/fd0 2.4.2-2</B
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></PRE
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></FONT
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></TD
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></TR
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></TABLE
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><P
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></P
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></DIV
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><P
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>Under <SPAN
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CLASS="PRODUCTNAME"
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>Debian
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<SPAN
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CLASS="ACRONYM"
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>GNU</SPAN
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>/Linux</SPAN
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> the boot diskette is
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created by determining the version of the running kernel and then
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using that version to write the boot diskette</P
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><DIV
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CLASS="INFORMALFIGURE"
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><A
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NAME="PREPARATION-FALLBACK-DEBIANDISK"
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></A
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><P
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></P
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><TABLE
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BORDER="1"
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BGCOLOR="#E0E0E0"
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WIDTH="100%"
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><TR
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><TD
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><FONT
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COLOR="#000000"
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><PRE
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CLASS="SCREEN"
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><TT
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CLASS="PROMPT"
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>bash#</TT
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> <B
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CLASS="COMMAND"
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>mkboot /boot/vmlinuz-2.4.2-2</B
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></PRE
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></FONT
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></TD
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></TR
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></TABLE
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><P
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></P
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></DIV
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><P
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>An alternative fallback position is have a rescue diskette
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with the machine. A common choice is <A
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HREF="http://www.toms.net/rb/"
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TARGET="_top"
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>Tom's root boot</A
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>.</P
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></DIV
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><DIV
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CLASS="NAVFOOTER"
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><HR
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ALIGN="LEFT"
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WIDTH="100%"><TABLE
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SUMMARY="Footer navigation table"
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><TR
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><TD
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WIDTH="33%"
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ALIGN="left"
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VALIGN="top"
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><A
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HREF="preparation.html"
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ACCESSKEY="P"
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>Prev</A
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></TD
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><TD
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WIDTH="34%"
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ALIGN="center"
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VALIGN="top"
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HREF="index.html"
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>Home</A
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></TD
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ALIGN="right"
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VALIGN="top"
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HREF="preparation-setport.html"
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ACCESSKEY="N"
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>Next</A
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WIDTH="33%"
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ALIGN="left"
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VALIGN="top"
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>Preparation</TD
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><TD
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WIDTH="34%"
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VALIGN="top"
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><TD
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WIDTH="33%"
|
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ALIGN="right"
|
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VALIGN="top"
|
|
>Select a serial port</TD
|
|
></TR
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></TABLE
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></BODY
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> |