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  • Committer: Bazaar Package Importer
  • Author(s): Andres Rodriguez
  • Date: 2011-07-05 15:40:13 UTC
  • mfrom: (1.4.6 upstream)
  • Revision ID: james.westby@ubuntu.com-20110705154013-f9l32owj6mi9e1p0
Tags: 2:8.3.11-0ubuntu1
* New upstream release
* debian/patches/01_ubuntu_cn_idx.dpatch: Refreshed.

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documentation/drbdsetup.xml
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      <arg choice="opt" rep="norepeat">-d<arg choice="req" rep="norepeat"><replaceable>hash_alg</replaceable></arg></arg>
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      <arg choice="opt" rep="norepeat">-o</arg>
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      <arg choice="opt" rep="norepeat">-n</arg>
 
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      <arg choice="opt" rep="norepeat">-g<arg choice="req" rep="norepeat"><replaceable>congestion_policy</replaceable></arg></arg>
 
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      <arg choice="opt" rep="norepeat">-f<arg choice="req" rep="norepeat"><replaceable>val</replaceable></arg></arg>
 
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      <arg choice="opt" rep="norepeat">-h<arg choice="req" rep="norepeat"><replaceable>val</replaceable></arg></arg>
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    </cmdsynopsis>
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    <cmdsynopsis sepchar=" ">
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      <command moreinfo="none">drbdsetup</command>
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          <option>--on-io-error <replaceable>err_handler</replaceable></option></term>
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          <listitem>
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            <para>            If the driver of the <replaceable>lower_device</replaceable>
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              reports an error to DRBD, DRBD will either pass the error
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              to the upper layers of the operating system, call a helper
 
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              reports an error to DRBD, DRBD will mark the disk as inconsistent,
 
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              call a helper
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              program, or detach the device from its backing storage and
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              perform all further IO by requesting it from the peer. The
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              valid <replaceable>err_handlers</replaceable> are:
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            </para>
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          </listitem>
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        </varlistentry>
 
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        <varlistentry>
 
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          <term><option>-g</option>, <option>--on-congestion </option><replaceable>congestion_policy</replaceable></term>
 
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          <term><option>-f</option>, <option>--congestion-fill </option><replaceable>fill_threshold</replaceable></term>
 
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          <term><option>-h</option>, <option>--congestion-extents </option><replaceable>active_extents_threshold</replaceable></term>
 
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          <listitem>
 
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            <para>By default DRBD blocks when the available TCP send queue becomes full.
 
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              That means it will slow down the application that generates the write
 
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              requests that cause DRBD to send more data down that TCP connection.
 
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            </para>
 
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            <para>When DRBD is deployed with DRBD-proxy it might be more desirable that
 
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              DRBD goes into AHEAD/BEHIND mode shortly before the send queue becomes full.
 
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              In AHEAD/BEHIND mode DRBD does no longer replicate data, but still keeps
 
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              the connection open.</para>
 
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            <para>The advantage of the AHEAD/BEHIND mode is that the
 
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              application is not slowed down, even if DRBD-proxy's buffer is
 
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              not sufficient to buffer all write requests. The downside is that
 
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              the peer node falls behind, and that a resync will be necessary to
 
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              bring it back into sync. During that resync the peer node will have
 
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              an inconsistent disk. </para>
 
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            <para>Available <replaceable>congestion_policy</replaceable>s are <option>block</option>
 
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              and <option>pull-ahead</option>. The default is <option>block</option>.
 
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              <replaceable>Fill_threshold</replaceable> might be in the range of 0 to 10GiBytes. The
 
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              default is 0 which disables the check. <replaceable>Active_extents_threshold</replaceable>
 
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              has the same limits as <option>al-extents</option>.</para>
 
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            <para>The AHEAD/BEHIND mode and its settings are available since DRBD 8.3.10.</para>
 
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          </listitem>
 
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        </varlistentry>
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      </variablelist>
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    </refsect2>
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    <refsect2>