<div id="docs-body">
 <div class="section">
  <div class="titlepage">
   <div>
    <div>
     <h3 class="title">
      <a name="mysql-cluster-programs-ndb-redo-log-reader">
      </a>
      25.5.22 ndb_redo_log_reader — Check and Print Content of Cluster Redo Log
     </h3>
    </div>
   </div>
  </div>
  <a class="indexterm" name="idm46045100007408">
  </a>
  <p>
   Reads a redo log file, checking it for errors, printing its
        contents in a human-readable format, or both.
   <a class="link" href="mysql-cluster-programs-ndb-redo-log-reader.html" title="25.5.22 ndb_redo_log_reader — Check and Print Content of Cluster Redo Log">
    <span class="command">
     <strong>
      ndb_redo_log_reader
     </strong>
    </span>
   </a>
   is intended for use
        primarily by NDB Cluster developers and Support personnel in
        debugging and diagnosing problems.
  </p>
  <p>
   This utility remains under development, and its syntax and
        behavior are subject to change in future NDB Cluster releases.
  </p>
  <p>
   The C++ source files for
   <a class="link" href="mysql-cluster-programs-ndb-redo-log-reader.html" title="25.5.22 ndb_redo_log_reader — Check and Print Content of Cluster Redo Log">
    <span class="command">
     <strong>
      ndb_redo_log_reader
     </strong>
    </span>
   </a>
   can be found in the directory
   <code class="filename">
    /storage/ndb/src/kernel/blocks/dblqh/redoLogReader
   </code>
   .
  </p>
  <p>
   Options that can be used with
   <a class="link" href="mysql-cluster-programs-ndb-redo-log-reader.html" title="25.5.22 ndb_redo_log_reader — Check and Print Content of Cluster Redo Log">
    <span class="command">
     <strong>
      ndb_redo_log_reader
     </strong>
    </span>
   </a>
   are shown in the
        following table. Additional descriptions follow the table.
  </p>
  <p>
  </p>
  <h4>
   <a name="idm46045099998880">
   </a>
   Usage
  </h4>
  <div class="copytoclipboard-wrapper">
   <pre class="programlisting one-line language-terminal"><div class="docs-select-all right" id="sa82684379"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal">ndb_redo_log_reader <em class="replaceable">file_name</em> <span class="token punctuation">[</span><em class="replaceable">options</em><span class="token punctuation">]</span></code></pre>
  </div>
  <p>
   <em class="replaceable">
    <code>
     file_name
    </code>
   </em>
   is the name of a cluster
        redo log file. redo log files are located in the numbered
        directories under the data node's data directory
        (
   <a class="link" href="mysql-cluster-ndbd-definition.html#ndbparam-ndbd-datadir">
    <code class="literal">
     DataDir
    </code>
   </a>
   ); the path
        under this directory to the redo log files matches the pattern
   <code class="filename">
    ndb_
    <em class="replaceable">
     <code>
      nodeid
     </code>
    </em>
    _fs/D
    <em class="replaceable">
     <code>
      #
     </code>
    </em>
    /DBLQH/S
    <em class="replaceable">
     <code>
      #
     </code>
    </em>
    .FragLog
   </code>
   .
   <em class="replaceable">
    <code>
     nodeid
    </code>
   </em>
   is the data node's node
        ID. The two instances of
   <em class="replaceable">
    <code>
     #
    </code>
   </em>
   each
        represent a number (not necessarily the same number); the number
        following
   <code class="literal">
    D
   </code>
   is in the range 8-39 inclusive;
        the range of the number following
   <code class="literal">
    S
   </code>
   varies
        according to the value of the
   <a class="link" href="mysql-cluster-ndbd-definition.html#ndbparam-ndbd-nooffragmentlogfiles">
    <code class="literal">
     NoOfFragmentLogFiles
    </code>
   </a>
   configuration parameter, whose default value is 16; thus, the
        default range of the number in the file name is 0-15 inclusive.
        For more information, see
   <a class="ulink" href="/doc/ndb-internals/en/ndb-internals-ndbd-filesystemdir-files.html" target="_top">
    NDB Cluster Data Node File System Directory
   </a>
   .
  </p>
  <p>
   The name of the file to be read may be followed by one or more
        of the options listed here:
  </p>
  <div class="itemizedlist">
   <ul class="itemizedlist" style="list-style-type: disc; ">
    <li class="listitem">
     <p>
      <a name="option_ndb_redo_log_reader_dump">
      </a>
      <a class="link" href="mysql-cluster-programs-ndb-redo-log-reader.html#option_ndb_redo_log_reader_dump">
       <code class="option">
        -dump
       </code>
      </a>
     </p>
     <a class="indexterm" name="idm46045099984384">
     </a>
     <a class="indexterm" name="idm46045099982896">
     </a>
     <div class="informaltable">
      <table frame="box" rules="all" summary="Properties for dump">
       <colgroup>
        <col style="width: 30%"/>
        <col style="width: 70%"/>
       </colgroup>
       <tbody>
        <tr>
         <th>
          Command-Line Format
         </th>
         <td>
          <code class="literal">
           -dump
          </code>
         </td>
        </tr>
       </tbody>
      </table>
     </div>
     <p>
      Print dump info.
     </p>
    </li>
    <li class="listitem">
     <p>
      <a name="option_ndb_redo_log_reader_file-key">
      </a>
      <a class="link" href="mysql-cluster-programs-ndb-redo-log-reader.html#option_ndb_redo_log_reader_file-key">
       <code class="option">
        --file-key
       </code>
      </a>
      ,
      <code class="option">
       -K
      </code>
     </p>
     <a class="indexterm" name="idm46045099972736">
     </a>
     <a class="indexterm" name="idm46045099971248">
     </a>
     <div class="informaltable">
      <table frame="box" rules="all" summary="Properties for file-key">
       <colgroup>
        <col style="width: 30%"/>
        <col style="width: 70%"/>
       </colgroup>
       <tbody>
        <tr>
         <th>
          Command-Line Format
         </th>
         <td>
          <code class="literal">
           --file-key=key
          </code>
         </td>
        </tr>
       </tbody>
      </table>
     </div>
     <p>
      Supply file decryption key using
      <code class="literal">
       stdin
      </code>
      ,
      <code class="literal">
       tty
      </code>
      , or a
      <code class="filename">
       my.cnf
      </code>
      file.
     </p>
    </li>
    <li class="listitem">
     <p>
      <a name="option_ndb_redo_log_reader_file-key-from-stdin">
      </a>
      <a class="link" href="mysql-cluster-programs-ndb-redo-log-reader.html#option_ndb_redo_log_reader_file-key-from-stdin">
       <code class="option">
        --file-key-from-stdin
       </code>
      </a>
     </p>
     <a class="indexterm" name="idm46045099959280">
     </a>
     <a class="indexterm" name="idm46045099957776">
     </a>
     <div class="informaltable">
      <table frame="box" rules="all" summary="Properties for file-key-from-stdin">
       <colgroup>
        <col style="width: 30%"/>
        <col style="width: 70%"/>
       </colgroup>
       <tbody>
        <tr>
         <th>
          Command-Line Format
         </th>
         <td>
          <code class="literal">
           --file-key-from-stdin
          </code>
         </td>
        </tr>
       </tbody>
      </table>
     </div>
     <p>
      Supply file decryption key using
      <code class="literal">
       stdin
      </code>
      .
     </p>
    </li>
    <li class="listitem">
     <a name="option_ndb_redo_log_reader_filedescriptors">
     </a>
     <div class="informaltable">
      <table frame="box" rules="all" summary="Properties for filedescriptors">
       <colgroup>
        <col style="width: 30%"/>
        <col style="width: 70%"/>
       </colgroup>
       <tbody>
        <tr>
         <th>
          Command-Line Format
         </th>
         <td>
          <code class="literal">
           -filedescriptors
          </code>
         </td>
        </tr>
       </tbody>
      </table>
     </div>
     <p>
      <a class="link" href="mysql-cluster-programs-ndb-redo-log-reader.html#option_ndb_redo_log_reader_filedescriptors">
       <code class="option">
        -filedescriptors
       </code>
      </a>
      :
            Print file descriptors only.
     </p>
    </li>
    <li class="listitem">
     <a name="option_ndb_redo_log_reader_help">
     </a>
     <div class="informaltable">
      <table frame="box" rules="all" summary="Properties for help">
       <colgroup>
        <col style="width: 30%"/>
        <col style="width: 70%"/>
       </colgroup>
       <tbody>
        <tr>
         <th>
          Command-Line Format
         </th>
         <td>
          <code class="literal">
           --help
          </code>
         </td>
        </tr>
       </tbody>
      </table>
     </div>
     <p>
      <a class="link" href="mysql-cluster-programs-ndb-redo-log-reader.html#option_ndb_redo_log_reader_help">
       <code class="option">
        --help
       </code>
      </a>
      : Print
            usage information.
     </p>
    </li>
    <li class="listitem">
     <p>
      <a name="option_ndb_redo_log_reader_lap">
      </a>
      <a class="link" href="mysql-cluster-programs-ndb-redo-log-reader.html#option_ndb_redo_log_reader_lap">
       <code class="option">
        -lap
       </code>
      </a>
     </p>
     <a class="indexterm" name="idm46045099931536">
     </a>
     <a class="indexterm" name="idm46045099930048">
     </a>
     <div class="informaltable">
      <table frame="box" rules="all" summary="Properties for lap">
       <colgroup>
        <col style="width: 30%"/>
        <col style="width: 70%"/>
       </colgroup>
       <tbody>
        <tr>
         <th>
          Command-Line Format
         </th>
         <td>
          <code class="literal">
           -lap
          </code>
         </td>
        </tr>
       </tbody>
      </table>
     </div>
     <p>
      Provide lap info, with max GCI started and completed.
     </p>
    </li>
    <li class="listitem">
     <a name="option_ndb_redo_log_reader_mbyte">
     </a>
     <div class="informaltable">
      <table frame="box" rules="all" summary="Properties for mbyte">
       <colgroup>
        <col style="width: 30%"/>
        <col style="width: 70%"/>
       </colgroup>
       <tbody>
        <tr>
         <th>
          Command-Line Format
         </th>
         <td>
          <code class="literal">
           -mbyte #
          </code>
         </td>
        </tr>
        <tr>
         <th>
          Type
         </th>
         <td>
          Numeric
         </td>
        </tr>
        <tr>
         <th>
          Default Value
         </th>
         <td>
          <code class="literal">
           0
          </code>
         </td>
        </tr>
        <tr>
         <th>
          Minimum Value
         </th>
         <td>
          <code class="literal">
           0
          </code>
         </td>
        </tr>
        <tr>
         <th>
          Maximum Value
         </th>
         <td>
          <code class="literal">
           15
          </code>
         </td>
        </tr>
       </tbody>
      </table>
     </div>
     <p>
      <a class="link" href="mysql-cluster-programs-ndb-redo-log-reader.html#option_ndb_redo_log_reader_mbyte">
       <code class="option">
        -mbyte
        <em class="replaceable">
         <code>
          #
         </code>
        </em>
       </code>
      </a>
      : Starting megabyte.
     </p>
     <p>
      <em class="replaceable">
       <code>
        #
       </code>
      </em>
      is an integer in the range 0 to
            15, inclusive.
     </p>
    </li>
    <li class="listitem">
     <a name="option_ndb_redo_log_reader_mbyteheaders">
     </a>
     <div class="informaltable">
      <table frame="box" rules="all" summary="Properties for mbyteheaders">
       <colgroup>
        <col style="width: 30%"/>
        <col style="width: 70%"/>
       </colgroup>
       <tbody>
        <tr>
         <th>
          Command-Line Format
         </th>
         <td>
          <code class="literal">
           -mbyteheaders
          </code>
         </td>
        </tr>
       </tbody>
      </table>
     </div>
     <p>
      <a class="link" href="mysql-cluster-programs-ndb-redo-log-reader.html#option_ndb_redo_log_reader_mbyteheaders">
       <code class="option">
        -mbyteheaders
       </code>
      </a>
      :
            Show only the first page header of every megabyte in the
            file.
     </p>
    </li>
    <li class="listitem">
     <a name="option_ndb_redo_log_reader_noprint">
     </a>
     <div class="informaltable">
      <table frame="box" rules="all" summary="Properties for noprint">
       <colgroup>
        <col style="width: 30%"/>
        <col style="width: 70%"/>
       </colgroup>
       <tbody>
        <tr>
         <th>
          Command-Line Format
         </th>
         <td>
          <code class="literal">
           -noprint
          </code>
         </td>
        </tr>
       </tbody>
      </table>
     </div>
     <p>
      <a class="link" href="mysql-cluster-programs-ndb-redo-log-reader.html#option_ndb_redo_log_reader_noprint">
       <code class="option">
        -noprint
       </code>
      </a>
      : Do not
            print the contents of the log file.
     </p>
    </li>
    <li class="listitem">
     <a name="option_ndb_redo_log_reader_nocheck">
     </a>
     <div class="informaltable">
      <table frame="box" rules="all" summary="Properties for nocheck">
       <colgroup>
        <col style="width: 30%"/>
        <col style="width: 70%"/>
       </colgroup>
       <tbody>
        <tr>
         <th>
          Command-Line Format
         </th>
         <td>
          <code class="literal">
           -nocheck
          </code>
         </td>
        </tr>
       </tbody>
      </table>
     </div>
     <p>
      <a class="link" href="mysql-cluster-programs-ndb-redo-log-reader.html#option_ndb_redo_log_reader_nocheck">
       <code class="option">
        -nocheck
       </code>
      </a>
      : Do not
            check the log file for errors.
     </p>
    </li>
    <li class="listitem">
     <a name="option_ndb_redo_log_reader_page">
     </a>
     <div class="informaltable">
      <table frame="box" rules="all" summary="Properties for page">
       <colgroup>
        <col style="width: 30%"/>
        <col style="width: 70%"/>
       </colgroup>
       <tbody>
        <tr>
         <th>
          Command-Line Format
         </th>
         <td>
          <code class="literal">
           -page #
          </code>
         </td>
        </tr>
        <tr>
         <th>
          Type
         </th>
         <td>
          Integer
         </td>
        </tr>
        <tr>
         <th>
          Default Value
         </th>
         <td>
          <code class="literal">
           0
          </code>
         </td>
        </tr>
        <tr>
         <th>
          Minimum Value
         </th>
         <td>
          <code class="literal">
           0
          </code>
         </td>
        </tr>
        <tr>
         <th>
          Maximum Value
         </th>
         <td>
          <code class="literal">
           31
          </code>
         </td>
        </tr>
       </tbody>
      </table>
     </div>
     <p>
      <a class="link" href="mysql-cluster-programs-ndb-redo-log-reader.html#option_ndb_redo_log_reader_page">
       <code class="option">
        -page
        <em class="replaceable">
         <code>
          #
         </code>
        </em>
       </code>
      </a>
      : Start at this page.
     </p>
     <p>
      <em class="replaceable">
       <code>
        #
       </code>
      </em>
      is an integer in the range 0 to
            31, inclusive.
     </p>
    </li>
    <li class="listitem">
     <a name="option_ndb_redo_log_reader_pageheaders">
     </a>
     <div class="informaltable">
      <table frame="box" rules="all" summary="Properties for pageheaders">
       <colgroup>
        <col style="width: 30%"/>
        <col style="width: 70%"/>
       </colgroup>
       <tbody>
        <tr>
         <th>
          Command-Line Format
         </th>
         <td>
          <code class="literal">
           -pageheaders
          </code>
         </td>
        </tr>
       </tbody>
      </table>
     </div>
     <p>
      <a class="link" href="mysql-cluster-programs-ndb-redo-log-reader.html#option_ndb_redo_log_reader_pageheaders">
       <code class="option">
        -pageheaders
       </code>
      </a>
      :
            Show page headers only.
     </p>
    </li>
    <li class="listitem">
     <a name="option_ndb_redo_log_reader_pageindex">
     </a>
     <div class="informaltable">
      <table frame="box" rules="all" summary="Properties for pageindex">
       <colgroup>
        <col style="width: 30%"/>
        <col style="width: 70%"/>
       </colgroup>
       <tbody>
        <tr>
         <th>
          Command-Line Format
         </th>
         <td>
          <code class="literal">
           -pageindex #
          </code>
         </td>
        </tr>
        <tr>
         <th>
          Type
         </th>
         <td>
          Integer
         </td>
        </tr>
        <tr>
         <th>
          Default Value
         </th>
         <td>
          <code class="literal">
           12
          </code>
         </td>
        </tr>
        <tr>
         <th>
          Minimum Value
         </th>
         <td>
          <code class="literal">
           12
          </code>
         </td>
        </tr>
        <tr>
         <th>
          Maximum Value
         </th>
         <td>
          <code class="literal">
           8191
          </code>
         </td>
        </tr>
       </tbody>
      </table>
     </div>
     <p>
      <a class="link" href="mysql-cluster-programs-ndb-redo-log-reader.html#option_ndb_redo_log_reader_pageindex">
       <code class="option">
        -pageindex
        <em class="replaceable">
         <code>
          #
         </code>
        </em>
       </code>
      </a>
      : Start at this page
            index.
     </p>
     <p>
      <em class="replaceable">
       <code>
        #
       </code>
      </em>
      is an integer between 12 and
            8191, inclusive.
     </p>
    </li>
    <li class="listitem">
     <p>
      <a name="option_ndb_redo_log_reader_twiddle">
      </a>
      <a class="link" href="mysql-cluster-programs-ndb-redo-log-reader.html#option_ndb_redo_log_reader_twiddle">
       <code class="option">
        -twiddle
       </code>
      </a>
     </p>
     <a class="indexterm" name="idm46045099834224">
     </a>
     <a class="indexterm" name="idm46045099832736">
     </a>
     <div class="informaltable">
      <table frame="box" rules="all" summary="Properties for twiddle">
       <colgroup>
        <col style="width: 30%"/>
        <col style="width: 70%"/>
       </colgroup>
       <tbody>
        <tr>
         <th>
          Command-Line Format
         </th>
         <td>
          <code class="literal">
           -twiddle
          </code>
         </td>
        </tr>
       </tbody>
      </table>
     </div>
     <p>
      Bit-shifted dump.
     </p>
    </li>
   </ul>
  </div>
  <p>
   Like
   <a class="link" href="mysql-cluster-programs-ndb-print-backup-file.html" title="25.5.17 ndb_print_backup_file — Print NDB Backup File Contents">
    <span class="command">
     <strong>
      ndb_print_backup_file
     </strong>
    </span>
   </a>
   and
   <a class="link" href="mysql-cluster-programs-ndb-print-schema-file.html" title="25.5.20 ndb_print_schema_file — Print NDB Schema File Contents">
    <span class="command">
     <strong>
      ndb_print_schema_file
     </strong>
    </span>
   </a>
   (and unlike most of the
   <a class="link" href="mysql-cluster.html" title="Chapter 25 MySQL NDB Cluster 8.4">
    <code class="literal">
     NDB
    </code>
   </a>
   utilities that are intended to
        be run on a management server host or to connect to a management
        server)
   <a class="link" href="mysql-cluster-programs-ndb-redo-log-reader.html" title="25.5.22 ndb_redo_log_reader — Check and Print Content of Cluster Redo Log">
    <span class="command">
     <strong>
      ndb_redo_log_reader
     </strong>
    </span>
   </a>
   must be run on a
        cluster data node, since it accesses the data node file system
        directly. Because it does not make use of the management server,
        this utility can be used when the management server is not
        running, and even when the cluster has been completely shut
        down.
  </p>
 </div>
 <br/>
</div>
