176 lines
3.6 KiB
HTML
176 lines
3.6 KiB
HTML
<HTML
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><HEAD
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><TITLE
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>Farming</TITLE
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><META
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NAME="GENERATOR"
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CONTENT="Modular DocBook HTML Stylesheet Version 1.76b+
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"><LINK
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REL="HOME"
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TITLE="Jabber Server Farming How-To"
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HREF="index.html"><LINK
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REL="UP"
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TITLE="Introduction to Jabberd and Farming"
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HREF="introduction.html"><LINK
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REL="PREVIOUS"
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TITLE="Jabberd - The Jabber.org Jabber Server"
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HREF="jabberserver.html"><LINK
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REL="NEXT"
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TITLE="Implementing the Farm"
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HREF="implementation.html"></HEAD
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><BODY
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CLASS="section"
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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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CELLPADDING="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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>Jabber Server Farming How-To</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="jabberserver.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 2. Introduction to Jabberd and Farming</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="implementation.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="section"
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><H1
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CLASS="section"
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><A
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NAME="farming">2.2. Farming</H1
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><P
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> This is an interesting topic. When you think of a
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server you tend to think of a single machine running
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a single program. Farming is the idea of multiple machines
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running multiple programs that all act together to
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appear to be one machine/program.
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</P
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><P
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> Why farming? Two reasons with equal importance. Scalability
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and Reliability.
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</P
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><P
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> Scalability is the idea of allowing something to handle
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many many more connections/transactions at the same time.
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A typcial web server can handle say 1000 connections a
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second, but 10 web servers acting together can provide
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10,000 connections per second.
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</P
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><P
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> Reliability is the idea that even if a piece of the system
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goes down, the system does not. There is no single point
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of failure, and there is built in redundancy to ensure
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that something is there to pick up the slack if something
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goes down. In the web server example, if one web server
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goes down you could not send any connections to it until
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it is back up, thus ensuring that your web site is always
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up.
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</P
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><P
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> Both of these ideas are crucial to a successful Farming
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strategy. Each wants to push the design into a different
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direction, but they can be reconciled into a single
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design that can scale and is reliable at the same time.
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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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WIDTH="100%"
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BORDER="0"
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CELLPADDING="0"
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CELLSPACING="0"
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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="jabberserver.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="implementation.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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>Jabberd - The Jabber.org Jabber Server</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="introduction.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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>Implementing the Farm</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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> |