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@@ -1099,8 +1099,22 @@ server.3=zoo3:2888:3888</span>
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non-authenticated UDP-based version of fast leader election, "2"
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corresponds to the authenticated UDP-based version of fast
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leader election, and "3" corresponds to TCP-based version of
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- fast leader election. Currently, only 0 and 3 are supported, 3
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- being the default</p>
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+ fast leader election. Currently, algorithm 3 is the default</p>
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+<div class="note">
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+<div class="label">Note</div>
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+<div class="content">
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+
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+<p> The implementations of leader election
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+ 1 and 2 are currently not supported, and we have the intention
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+ of deprecating them in the near future. Implementations 0 and 3 are
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+ currently supported, and we plan to keep supporting them in the near future.
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+ To avoid having to support multiple versions of leader election unecessarily,
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+ we may eventually consider deprecating algorithm 0 as well, but we will plan
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+ according to the needs of the community.
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+ </p>
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+
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+</div>
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+</div>
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</dd>
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@@ -1207,7 +1221,7 @@ server.3=zoo3:2888:3888</span>
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</dl>
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<p></p>
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-<a name="N103B5"></a><a name="sc_authOptions"></a>
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+<a name="N103BA"></a><a name="sc_authOptions"></a>
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<h4>Authentication & Authorization Options</h4>
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<p>The options in this section allow control over
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authentication/authorization performed by the service.</p>
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@@ -1241,7 +1255,7 @@ server.3=zoo3:2888:3888</span>
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</dd>
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</dl>
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-<a name="N103D8"></a><a name="Unsafe+Options"></a>
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+<a name="N103DD"></a><a name="Unsafe+Options"></a>
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<h4>Unsafe Options</h4>
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<p>The following options can be useful, but be careful when you use
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them. The risk of each is explained along with the explanation of what
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@@ -1286,7 +1300,7 @@ server.3=zoo3:2888:3888</span>
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</dd>
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</dl>
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-<a name="N1040A"></a><a name="sc_zkCommands"></a>
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+<a name="N1040F"></a><a name="sc_zkCommands"></a>
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<h3 class="h4">ZooKeeper Commands: The Four Letter Words</h3>
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<p>ZooKeeper responds to a small set of commands. Each command is
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composed of four letters. You issue the commands to ZooKeeper via telnet
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@@ -1407,7 +1421,7 @@ server.3=zoo3:2888:3888</span>
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<pre class="code">$ echo ruok | nc 127.0.0.1 5111
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imok
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</pre>
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-<a name="N10472"></a><a name="sc_dataFileManagement"></a>
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+<a name="N10477"></a><a name="sc_dataFileManagement"></a>
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<h3 class="h4">Data File Management</h3>
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<p>ZooKeeper stores its data in a data directory and its transaction
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log in a transaction log directory. By default these two directories are
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@@ -1415,7 +1429,7 @@ imok
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transaction log files in a separate directory than the data files.
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Throughput increases and latency decreases when transaction logs reside
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on a dedicated log devices.</p>
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-<a name="N1047B"></a><a name="The+Data+Directory"></a>
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+<a name="N10480"></a><a name="The+Data+Directory"></a>
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<h4>The Data Directory</h4>
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<p>This directory has two files in it:</p>
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<ul>
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@@ -1461,14 +1475,14 @@ imok
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idempotent nature of its updates. By replaying the transaction log
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against fuzzy snapshots ZooKeeper gets the state of the system at the
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end of the log.</p>
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-<a name="N104B7"></a><a name="The+Log+Directory"></a>
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+<a name="N104BC"></a><a name="The+Log+Directory"></a>
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<h4>The Log Directory</h4>
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<p>The Log Directory contains the ZooKeeper transaction logs.
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Before any update takes place, ZooKeeper ensures that the transaction
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that represents the update is written to non-volatile storage. A new
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log file is started each time a snapshot is begun. The log file's
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suffix is the first zxid written to that log.</p>
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-<a name="N104C1"></a><a name="sc_filemanagement"></a>
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+<a name="N104C6"></a><a name="sc_filemanagement"></a>
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<h4>File Management</h4>
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<p>The format of snapshot and log files does not change between
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standalone ZooKeeper servers and different configurations of
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@@ -1488,7 +1502,7 @@ imok
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this document for more details on setting a retention policy
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and maintenance of ZooKeeper storage.
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</p>
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-<a name="N104D6"></a><a name="sc_commonProblems"></a>
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+<a name="N104DB"></a><a name="sc_commonProblems"></a>
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<h3 class="h4">Things to Avoid</h3>
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<p>Here are some common problems you can avoid by configuring
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ZooKeeper correctly:</p>
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@@ -1542,7 +1556,7 @@ imok
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</dd>
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</dl>
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-<a name="N104FA"></a><a name="sc_bestPractices"></a>
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+<a name="N104FF"></a><a name="sc_bestPractices"></a>
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<h3 class="h4">Best Practices</h3>
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<p>For best results, take note of the following list of good
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Zookeeper practices:</p>
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Mahadev Konar