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<div class="content documentation">
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		<h1>Documentation</h1>
    <h3>Kafka 0.9.0</h3>
		<p>
    	Prior releases: <a href="/07/documentation.html">0.7.x</a>, <a href="/08/documentation.html">0.8.0</a>, <a href="/081/documentation.html">0.8.1.X</a>, <a href="/082/documentation.html">0.8.2.X</a>.
		</p>

    <ul class="toc">
        <li><a href="#gettingStarted">1. Getting Started</a>
             <ul>
                 <li><a href="#introduction">1.1 Introduction</a>
                 <li><a href="#uses">1.2 Use Cases</a>
                 <li><a href="#quickstart">1.3 Quick Start</a>
                 <li><a href="#ecosystem">1.4 Ecosystem</a>
                 <li><a href="#upgrade">1.5 Upgrading</a>
             </ul>
        </li>
        <li><a href="#api">2. API</a>
              <ul>
                  <li><a href="#producerapi">2.1 Producer API</a>
                  <li><a href="#consumerapi">2.2 Consumer API</a>
                      <ul>
                          <li><a href="#highlevelconsumerapi">2.2.1 Old High Level Consumer API</a>
                          <li><a href="#simpleconsumerapi">2.2.2 Old Simple Consumer API</a>
                          <li><a href="#newconsumerapi">2.2.3 New Consumer API</a>
                      </ul>
              </ul>
        </li>
        <li><a href="#configuration">3. Configuration</a>
            <ul>
                <li><a href="#brokerconfigs">3.1 Broker Configs</a>
                <li><a href="#producerconfigs">3.2 Producer Configs</a>
                <li><a href="#consumerconfigs">3.3 Consumer Configs</a>
                    <ul>
                        <li><a href="#oldconsumerconfigs">3.3.1 Old Consumer Configs</a>
                        <li><a href="#newconsumerconfigs">3.3.2 New Consumer Configs</a>
                    </ul>
                <li><a href="#connectconfigs">3.4 Kafka Connect Configs</a>
            </ul>
        </li>
        <li><a href="#design">4. Design</a>
            <ul>
                 <li><a href="#majordesignelements">4.1 Motivation</a>
                 <li><a href="#persistence">4.2 Persistence</a>
                 <li><a href="#maximizingefficiency">4.3 Efficiency</a>
                 <li><a href="#theproducer">4.4 The Producer</a>
                 <li><a href="#theconsumer">4.5 The Consumer</a>
                 <li><a href="#semantics">4.6 Message Delivery Semantics</a>
                 <li><a href="#replication">4.7 Replication</a>
                 <li><a href="#compaction">4.8 Log Compaction</a>
                 <li><a href="#design_quotas">4.9 Quotas</a>
            </ul>
        </li>
        <li><a href="#implementation">5. Implementation</a>
            <ul>
                  <li><a href="#apidesign">5.1 API Design</a>
                  <li><a href="#networklayer">5.2 Network Layer</a>
                  <li><a href="#messages">5.3 Messages</a>
                  <li><a href="#messageformat">5.4 Message format</a>
                  <li><a href="#log">5.5 Log</a>
                  <li><a href="#distributionimpl">5.6 Distribution</a>
            </ul>
        </li>
        <li><a href="#operations">6. Operations</a>
            <ul>
                 <li><a href="#basic_ops">6.1 Basic Kafka Operations</a>
                    <ul>
                         <li><a href="#basic_ops_add_topic">Adding and removing topics</a>
                         <li><a href="#basic_ops_modify_topic">Modifying topics</a>
                         <li><a href="#basic_ops_restarting">Graceful shutdown</a>
                         <li><a href="#basic_ops_leader_balancing">Balancing leadership</a>
                         <li><a href="#basic_ops_consumer_lag">Checking consumer position</a>
                         <li><a href="#basic_ops_mirror_maker">Mirroring data between clusters</a>
                         <li><a href="#basic_ops_cluster_expansion">Expanding your cluster</a>
                         <li><a href="#basic_ops_decommissioning_brokers">Decommissioning brokers</a>
                         <li><a href="#basic_ops_increase_replication_factor">Increasing replication factor</a>
                    </ul>
                 <li><a href="#datacenters">6.2 Datacenters</a>
                 <li><a href="#config">6.3 Important Configs</a>
                     <ul>
                         <li><a href="#serverconfig">Important Server Configs</a>
                         <li><a href="#clientconfig">Important Client Configs</a>
                         <li><a href="#prodconfig">A Production Server Configs</a>
                     </ul>
                   <li><a href="#java">6.4 Java Version</a>
                   <li><a href="#hwandos">6.5 Hardware and OS</a>
                    <ul>
                        <li><a href="#os">OS</a>
                        <li><a href="#diskandfs">Disks and Filesystems</a>
                        <li><a href="#appvsosflush">Application vs OS Flush Management</a>
                        <li><a href="#linuxflush">Linux Flush Behavior</a>
                        <li><a href="#ext4">Ext4 Notes</a>
                    </ul>
                  <li><a href="#monitoring">6.6 Monitoring</a>
                  <li><a href="#zk">6.7 ZooKeeper</a>
                    <ul>
                        <li><a href="#zkversion">Stable Version</a>
                        <li><a href="#zkops">Operationalization</a>
                    </ul>
            </ul>
        </li>
        <li><a href="#security">7. Security</a>
            <ul>
                <li><a href="#security_overview">7.1 Security Overview</a></li>
                <li><a href="#security_ssl">7.2 Encryption and Authentication using SSL</a></li>
                <li><a href="#security_sasl">7.3 Authentication using SASL</a></li>
                <li><a href="#security_authz">7.4 Authorization and ACLs</a></li>
                <li><a href="#zk_authz">7.5 ZooKeeper Authentication</a></li>
                <ul>
                    <li><a href="#zk_authz_new">New Clusters</a></li>
                    <li><a href="#zk_authz_migration">Migrating Clusters</a></li>
                    <li><a href="#zk_authz_ensemble">Migrating the ZooKeeper Ensemble</a></li>
                </ul>
            </ul>
        </li>
        <li><a href="#connect">8. Kafka Connect</a>
            <ul>
                <li><a href="#connect_overview">8.1 Overview</a></li>
                <li><a href="#connect_user">8.2 User Guide</a></li>
                <li><a href="#connect_development">8.3 Connector Development Guide</a></li>
            </ul>
        </li>
    </ul>

    <h2><a id="gettingStarted" href="#gettingStarted">1. Getting Started</a></h2>
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    <h2><a id="api" href="#api">2. API</a></h2>

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    <h2><a id="configuration" href="#configuration">3. Configuration</a></h2>

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    <h2><a id="design" href="#design">4. Design</a></h2>

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    <h2><a id="implementation" href="#implementation">5. Implementation</a></h2>

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    <h2><a id="operations" href="#operations">6. Operations</a></h2>

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    <h2><a id="security" href="#security">7. Security</a></h2>
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    <h2><a id="connect" href="#connect">8. Kafka Connect</a></h2>
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