apache
/
zookeeper
spegling av https://gitee.com/apache/zookeeper.git


			
				
					
						
						
							123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286287288289290291292293294295296297298299300301302303304305306307308309310311312313314315316317318319320321322323324325326327328329330331332333334335336337338339340341342343344345346347348349350351352353354355356357358359360361362363364365366367368369370371372373374375376377378379380381382383384385386387388389390391392393394395396397398399400401402403404405406407408409410411412413414415416417418419420421422423424425426427428429430431432433434435436437438439440441442443444445446447448
							<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<META http-equiv="Content-Type" content="text/html; charset=UTF-8">
<meta content="Apache Forrest" name="Generator">
<meta name="Forrest-version" content="0.9">
<meta name="Forrest-skin-name" content="pelt">
<title>BookKeeper Getting Started Guide</title>
<link type="text/css" href="skin/basic.css" rel="stylesheet">
<link media="screen" type="text/css" href="skin/screen.css" rel="stylesheet">
<link media="print" type="text/css" href="skin/print.css" rel="stylesheet">
<link type="text/css" href="skin/profile.css" rel="stylesheet">
<script src="skin/getBlank.js" language="javascript" type="text/javascript"></script><script src="skin/getMenu.js" language="javascript" type="text/javascript"></script><script src="skin/fontsize.js" language="javascript" type="text/javascript"></script>
<link rel="shortcut icon" href="images/favicon.ico">
</head>
<body onload="init()">
<script type="text/javascript">ndeSetTextSize();</script>
<div id="top">
<!--+
    |breadtrail
    +-->
<div class="breadtrail">
<a href="http://www.apache.org/">Apache</a> &gt; <a href="http://hadoop.apache.org/">Hadoop</a> &gt; <a href="http://hadoop.apache.org/zookeeper/">ZooKeeper</a><script src="skin/breadcrumbs.js" language="JavaScript" type="text/javascript"></script>
</div>
<!--+
    |header
    +-->
<div class="header">
<!--+
    |start group logo
    +-->
<div class="grouplogo">
<a href="http://hadoop.apache.org/"><img class="logoImage" alt="Hadoop" src="images/hadoop-logo.jpg" title="Apache Hadoop"></a>
</div>
<!--+
    |end group logo
    +-->
<!--+
    |start Project Logo
    +-->
<div class="projectlogo">
<a href="http://hadoop.apache.org/zookeeper/"><img class="logoImage" alt="ZooKeeper" src="images/zookeeper_small.gif" title="ZooKeeper: distributed coordination"></a>
</div>
<!--+
    |end Project Logo
    +-->
<!--+
    |start Search
    +-->
<div class="searchbox">
<form action="http://www.google.com/search" method="get" class="roundtopsmall">
<input value="hadoop.apache.org" name="sitesearch" type="hidden"><input onFocus="getBlank (this, 'Search the site with google');" size="25" name="q" id="query" type="text" value="Search the site with google">&nbsp; 
                    <input name="Search" value="Search" type="submit">
</form>
</div>
<!--+
    |end search
    +-->
<!--+
    |start Tabs
    +-->
<ul id="tabs">
<li>
<a class="unselected" href="http://hadoop.apache.org/zookeeper/">Project</a>
</li>
<li>
<a class="unselected" href="http://wiki.apache.org/hadoop/ZooKeeper">Wiki</a>
</li>
<li class="current">
<a class="selected" href="index.html">ZooKeeper 3.4 Documentation</a>
</li>
</ul>
<!--+
    |end Tabs
    +-->
</div>
</div>
<div id="main">
<div id="publishedStrip">
<!--+
    |start Subtabs
    +-->
<div id="level2tabs"></div>
<!--+
    |end Endtabs
    +-->
<script type="text/javascript"><!--
document.write("Last Published: " + document.lastModified);
//  --></script>
</div>
<!--+
    |breadtrail
    +-->
<div class="breadtrail">

             &nbsp;
           </div>
<!--+
    |start Menu, mainarea
    +-->
<!--+
    |start Menu
    +-->
<div id="menu">
<div onclick="SwitchMenu('menu_1.1', 'skin/')" id="menu_1.1Title" class="menutitle">Overview</div>
<div id="menu_1.1" class="menuitemgroup">
<div class="menuitem">
<a href="index.html">Welcome</a>
</div>
<div class="menuitem">
<a href="zookeeperOver.html">Overview</a>
</div>
<div class="menuitem">
<a href="zookeeperStarted.html">Getting Started</a>
</div>
<div class="menuitem">
<a href="releasenotes.html">Release Notes</a>
</div>
</div>
<div onclick="SwitchMenu('menu_1.2', 'skin/')" id="menu_1.2Title" class="menutitle">Developer</div>
<div id="menu_1.2" class="menuitemgroup">
<div class="menuitem">
<a href="api/index.html">API Docs</a>
</div>
<div class="menuitem">
<a href="zookeeperProgrammers.html">Programmer's Guide</a>
</div>
<div class="menuitem">
<a href="javaExample.html">Java Example</a>
</div>
<div class="menuitem">
<a href="zookeeperTutorial.html">Barrier and Queue Tutorial</a>
</div>
<div class="menuitem">
<a href="recipes.html">Recipes</a>
</div>
</div>
<div onclick="SwitchMenu('menu_selected_1.3', 'skin/')" id="menu_selected_1.3Title" class="menutitle" style="background-image: url('skin/images/chapter_open.gif');">BookKeeper</div>
<div id="menu_selected_1.3" class="selectedmenuitemgroup" style="display: block;">
<div class="menupage">
<div class="menupagetitle">Getting started</div>
</div>
<div class="menuitem">
<a href="bookkeeperOverview.html">Overview</a>
</div>
<div class="menuitem">
<a href="bookkeeperConfig.html">Setup guide</a>
</div>
<div class="menuitem">
<a href="bookkeeperProgrammer.html">Programmer's guide</a>
</div>
</div>
<div onclick="SwitchMenu('menu_1.4', 'skin/')" id="menu_1.4Title" class="menutitle">Admin &amp; Ops</div>
<div id="menu_1.4" class="menuitemgroup">
<div class="menuitem">
<a href="zookeeperAdmin.html">Administrator's Guide</a>
</div>
<div class="menuitem">
<a href="zookeeperQuotas.html">Quota Guide</a>
</div>
<div class="menuitem">
<a href="zookeeperJMX.html">JMX</a>
</div>
<div class="menuitem">
<a href="zookeeperObservers.html">Observers Guide</a>
</div>
</div>
<div onclick="SwitchMenu('menu_1.5', 'skin/')" id="menu_1.5Title" class="menutitle">Contributor</div>
<div id="menu_1.5" class="menuitemgroup">
<div class="menuitem">
<a href="zookeeperInternals.html">ZooKeeper Internals</a>
</div>
</div>
<div onclick="SwitchMenu('menu_1.6', 'skin/')" id="menu_1.6Title" class="menutitle">Miscellaneous</div>
<div id="menu_1.6" class="menuitemgroup">
<div class="menuitem">
<a href="http://wiki.apache.org/hadoop/ZooKeeper">Wiki</a>
</div>
<div class="menuitem">
<a href="http://wiki.apache.org/hadoop/ZooKeeper/FAQ">FAQ</a>
</div>
<div class="menuitem">
<a href="http://hadoop.apache.org/zookeeper/mailing_lists.html">Mailing Lists</a>
</div>
</div>
<div id="credit"></div>
<div id="roundbottom">
<img style="display: none" class="corner" height="15" width="15" alt="" src="skin/images/rc-b-l-15-1body-2menu-3menu.png"></div>
<!--+
  |alternative credits
  +-->
<div id="credit2"></div>
</div>
<!--+
    |end Menu
    +-->
<!--+
    |start content
    +-->
<div id="content">
<div title="Portable Document Format" class="pdflink">
<a class="dida" href="bookkeeperStarted.pdf"><img alt="PDF -icon" src="skin/images/pdfdoc.gif" class="skin"><br>
        PDF</a>
</div>
<h1>BookKeeper Getting Started Guide</h1>
<div id="front-matter">
<div id="minitoc-area">
<ul class="minitoc">
<li>
<a href="#bk_GettingStarted">Getting Started: Setting up BookKeeper to write logs.</a>
<ul class="minitoc">
<li>
<a href="#bk_Prerequisites">Pre-requisites</a>
</li>
<li>
<a href="#bk_Download">Download</a>
</li>
<li>
<a href="#bk_localBK">LocalBookKeeper</a>
</li>
<li>
<a href="#bk_setupBookies">Setting up bookies</a>
</li>
<li>
<a href="#bk_setupZK">Setting up ZooKeeper</a>
</li>
<li>
<a href="#bk_example">Example</a>
</li>
</ul>
</li>
</ul>
</div>
</div>
  

  
  
<a name="bk_GettingStarted"></a>
<h2 class="h3">Getting Started: Setting up BookKeeper to write logs.</h2>
<div class="section">
<p>This document contains information to get you started quickly with
    BookKeeper. It is aimed primarily at developers willing to try it out, and
    contains simple installation instructions for a simple BookKeeper installation
    and a simple programming example. For further programming detail, please refer to 
    <a href="bookkeeperProgrammer.html">BookKeeper Programmer's Guide</a>.
    </p>
<a name="bk_Prerequisites"></a>
<h3 class="h4">Pre-requisites</h3>
<p>See <a href="bookkeeperConfig.html#bk_sysReq">
    	      System Requirements</a> in the Admin guide.</p>
<a name="bk_Download"></a>
<h3 class="h4">Download</h3>
<p> BookKeeper is distributed along with ZooKeeper. To get a ZooKeeper distribution, 
			   download a recent
    	    <a href="http://hadoop.apache.org/zookeeper/releases.html">
        	  stable</a> release from one of the Apache Download
       	 Mirrors.</p>
<a name="bk_localBK"></a>
<h3 class="h4">LocalBookKeeper</h3>
<p> Under org.apache.bookkeeper.util, you'll find a java program
		called LocalBookKeeper.java that sets you up to run BookKeeper on a 
		single machine. This is far from ideal from a performance perspective,
		but the program is useful for both test and educational purposes.
		</p>
<a name="bk_setupBookies"></a>
<h3 class="h4">Setting up bookies</h3>
<p> If you're bold and you want more than just running things locally, then
		you'll need to run bookies in different servers. You'll need at least three bookies
		to start with.  
		</p>
<p>
		For each bookie, we need to execute a command like the following:
		</p>
<p>
<span class="codefrag computeroutput">
		java -cp .:./zookeeper-&lt;version&gt;-bookkeeper.jar:./zookeeper-&lt;version&gt;.jar\
		:lib/slf4j-api-1.6.1.jar:lib/slf4j-log4j12-1.6.1.jar:lib/log4j-1.2.15.jar -Dlog4j.configuration=log4j.properties\ 
		org.apache.bookkeeper.proto.BookieServer 3181 127.0.0.1:2181 /path_to_log_device/\
		/path_to_ledger_device/
		</span>
</p>
<p> "/path_to_log_device/" and "/path_to_ledger_device/" are different paths. Also, port 3181
		is the port that a bookie listens on for connection requests from clients. 127.0.0.1:2181 is the hostname:port 
		for the ZooKeeper server. In this example, the standalone ZooKeeper server is running locally on port 2181.
		If we had multiple ZooKeeper servers, this parameter would be a comma separated list of all the hostname:port
		values corresponding to them.
		</p>
<a name="bk_setupZK"></a>
<h3 class="h4">Setting up ZooKeeper</h3>
<p> ZooKeeper stores metadata on behalf of BookKeeper clients and bookies. To get a minimal 
	  	ZooKeeper installation to work with BookKeeper, we can set up one server running in
	  	standalone mode. Once we have the server running, we need to create a few znodes:
	  	</p>
<ol>
	  	
<li>
	  	
<p>
<span class="codefrag computeroutput">
	  	/ledgers	
	  	</span>
</p>
	  	
</li>
	  	
	  	
<li>
	  	
<p>
<span class="codefrag computeroutput">
	  	/ledgers/available
	  	</span>
</p>
	  	
</li>
	  	
	  	
<li>
	  	
<p> For each bookie, we add one znode such that the name of the znode is the
	  	concatenation of the machine name and the port number that the bookie is 
	  	listening on. For example, if a bookie is running on bookie.foo.com an is listening 
	  	on port 3181, we add a znode 
	  	<span class="codefrag computeroutput">/ledgers/available/bookie.foo.com:3181</span>.  
	  	</p>
	  	
</li>
	  	
</ol>
<a name="bk_example"></a>
<h3 class="h4">Example</h3>
<p>
	    In the following excerpt of code, we:
	    </p>
<ol>
	    	
<li>
	    	
<p>
	    	Create a ledger;
	    	</p>
	    	
</li>
	    	
	    	
<li>
	    	
<p>
	    	Write to the ledger;
	    	</p>
	    	
</li>
	    	
	    	
<li>
	    	
<p>
	    	Close the ledger;
	    	</p>
	    	
</li>
	    	
	    	
<li>
	    	
<p>
	    	Open the same ledger for reading;
	    	</p>
	    	
</li>
	    	
	    	
<li>
	    	
<p>
	    	Read from the ledger;
	    	</p>
	    	
</li>
	    	
	    	
<li>
	    	
<p>
	    	Close the ledger again;
	    	</p>
	    	
</li>
	    
</ol>
<pre class="code">
LedgerHandle lh = bkc.createLedger(ledgerPassword);
ledgerId = lh.getId();
ByteBuffer entry = ByteBuffer.allocate(4);

for(int i = 0; i &lt; 10; i++){
	entry.putInt(i);
	entry.position(0);
	entries.add(entry.array());				
	lh.addEntry(entry.array());
}
lh.close();
lh = bkc.openLedger(ledgerId, ledgerPassword);		
			
Enumeration&lt;LedgerEntry&gt; ls = lh.readEntries(0, 9);
int i = 0;
while(ls.hasMoreElements()){
	ByteBuffer origbb = ByteBuffer.wrap(
				entries.get(i++));
	Integer origEntry = origbb.getInt();
	ByteBuffer result = ByteBuffer.wrap(
				ls.nextElement().getEntry());

	Integer retrEntry = result.getInt();
}
lh.close();
	    </pre>
</div>

<p align="right">
<font size="-2"></font>
</p>
</div>
<!--+
    |end content
    +-->
<div class="clearboth">&nbsp;</div>
</div>
<div id="footer">
<!--+
    |start bottomstrip
    +-->
<div class="lastmodified">
<script type="text/javascript"><!--
document.write("Last Published: " + document.lastModified);
//  --></script>
</div>
<div class="copyright">
        Copyright &copy;
         2008 <a href="http://www.apache.org/licenses/">The Apache Software Foundation.</a>
</div>
<!--+
    |end bottomstrip
    +-->
</div>
</body>
</html>