183 lines
3.6 KiB
HTML
183 lines
3.6 KiB
HTML
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
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<HTML
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><HEAD
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><TITLE
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>NTP - Network Time Protocol</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="Linux System Administrators Guide"
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HREF="index.html"><LINK
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REL="UP"
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TITLE="Keeping Time"
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HREF="keeping-time.html"><LINK
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REL="PREVIOUS"
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TITLE="When the clock is wrong"
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HREF="clock-wrong.html"><LINK
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REL="NEXT"
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TITLE="Basic NTP configuration"
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HREF="basic-ntp-config.html"></HEAD
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><BODY
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CLASS="SECT1"
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BGCOLOR="#FFFFFF"
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TEXT="#000000"
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LINK="#0000FF"
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VLINK="#840084"
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ALINK="#0000FF"
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><DIV
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CLASS="NAVHEADER"
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><TABLE
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SUMMARY="Header navigation table"
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WIDTH="100%"
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BORDER="0"
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CELLSPACING="0"
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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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>Linux System Administrators Guide: </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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VALIGN="bottom"
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><A
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HREF="clock-wrong.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="80%"
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ALIGN="center"
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VALIGN="bottom"
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>Chapter 14. Keeping Time</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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HREF="basic-ntp-config.html"
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ACCESSKEY="N"
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>Next</A
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></TD
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></TR
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></TABLE
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><HR
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ALIGN="LEFT"
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WIDTH="100%"></DIV
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><DIV
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CLASS="SECT1"
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><H1
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CLASS="SECT1"
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><A
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NAME="NTP"
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></A
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>14.5. NTP - Network Time Protocol</H1
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><P
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> A networked computer (even if just over a modem) can
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check its own clock automatically by comparing it to the time
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on another computer known to keep accurate time. Network Time
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Protocol (or NTP) does exactly that. It is a method of verifying
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and correcting your computer's time by synchronizing it with a
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another system. With NTP your system's time can be maintained
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to within milliseconds of Coordinated Universal Time. Visit
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<A
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HREF="http://www.time.gov/about.html/"
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TARGET="_top"
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> http://www.time.gov/about.html</A
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> for more info.
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</P
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><P
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> For more casual Linux users, this is just a nice luxury.
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At my home all our clocks are set based upon what my Linux system
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says the time is. For larger organizations this "luxury" can
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become essential. Being able to search log files for events based
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upon time can make life a lot easier and take a lot of the "guess work"
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out of debugging.
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</P
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><P
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> Another example of how important NTP can be is with a SAN.
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Some SAN's require NTP be configured and running properly to allow
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for proper synchronization over filesystem usage, and proper
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timestamp control. Some SANs (and some applications) can become
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confused when dealing with files that have timestamps that are in
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the future.
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</P
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><P
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> Most Linux distributions come with a NTP package of some kind,
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either a .deb or .rpm package. You can use that to install NTP, or you
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can download the source files from <A
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HREF="http://www.ntp.org/downloads.html"
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TARGET="_top"
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> http://www.ntp.org/downloads.html</A
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> and compile it yourself. Either way,
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the basic configuration is the same.</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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><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="clock-wrong.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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><A
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HREF="index.html"
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ACCESSKEY="H"
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>Home</A
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></TD
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><TD
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WIDTH="33%"
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ALIGN="right"
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VALIGN="top"
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><A
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HREF="basic-ntp-config.html"
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ACCESSKEY="N"
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>Next</A
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></TD
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></TR
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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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>When the clock is wrong</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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><A
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HREF="keeping-time.html"
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ACCESSKEY="U"
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>Up</A
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></TD
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><TD
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WIDTH="33%"
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ALIGN="right"
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VALIGN="top"
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>Basic NTP configuration</TD
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></TR
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></TABLE
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></DIV
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></BODY
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></HTML
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> |