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It seems like we're doing something a bit wrong with Software RAID. There are some valid solutions here: <a class="https" href="https://wiki.ubuntu.com/ReliableRaid">https://wiki.ubuntu.com/ReliableRaid</a> which should be discussed and either refuted or implemented. <span class="anchor" id="line-11"></span><span class="anchor" id="line-12"></span><p class="line867"> <h2 id="Release_Note">Release Note</h2> <span class="anchor" id="line-13"></span><span class="anchor" id="line-14"></span><p class="line874">A number of long standing bugs in software RAID have been fixed, and a clear specification for how mdadm should work in Ubuntu has been written. <span class="anchor" id="line-15"></span><span class="anchor" id="line-16"></span><p class="line867"> <h2 id="Rationale">Rationale</h2> <span class="anchor" id="line-17"></span><span class="anchor" id="line-18"></span><p class="line874">mdadm, and the kernel's MD driver, are responsible for users' data storage. It must be as reliable as possible and the ways in which it works or does not work should be well known and documented. <span class="anchor" id="line-19"></span><span class="anchor" id="line-20"></span><p class="line874">Currently there are conflicting bug reports for mdadm in Ubuntu, and they all seem like potential bugs. This blueprint will attempt to remove any of the ambiguity of how mdadm is expected to work in Ubuntu. We also intend to assert the intentions of the upstream (mdadm and kernel md) authors' whenever possible. <span class="anchor" id="line-21"></span><span class="anchor" id="line-22"></span><p class="line867"> <h2 id="User_stories">User stories</h2> <span class="anchor" id="line-23"></span><span class="anchor" id="line-24"></span><p class="line874">As a system administrator, I want to have confidence that data stored on software RAID arrays will not be lost or corrupted on boot, and if there is a problem, I expect to be informed of it and for my configuration decisions to be respected. <span class="anchor" id="line-25"></span><span class="anchor" id="line-26"></span><p class="line867"> <h2 id="Assumptions">Assumptions</h2> <span class="anchor" id="line-27"></span><span class="anchor" id="line-28"></span><p class="line867"> <h2 id="Design">Design</h2> <span class="anchor" id="line-29"></span><span class="anchor" id="line-30"></span><p class="line874">The design is a large part of the work that needs to be done, as it involves reviewing existing reports and known fail modes and outlining how the system should handle them. <span class="anchor" id="line-31"></span><span class="anchor" id="line-32"></span><p class="line862">Note that this will incorporate elements from previous efforts to improve the RAID system, such as <a href="/ReliableRaid">ReliableRaid</a>, where possible. <span class="anchor" id="line-33"></span><span class="anchor" id="line-34"></span><p class="line867"> <h2 id="Implementation">Implementation</h2> <span class="anchor" id="line-35"></span><span class="anchor" id="line-36"></span><p class="line874">Pending Design section. <span class="anchor" id="line-37"></span><span class="anchor" id="line-38"></span><p class="line867"> <h2 id="Test.2FDemo_Plan">Test/Demo Plan</h2> <span class="anchor" id="line-39"></span><span class="anchor" id="line-40"></span><p class="line874">Testing will continue with the existing ISO testing for RAID 1, though other automated tests will be added if possible using the new automated server install testing suite. <span class="anchor" id="line-41"></span><span class="anchor" id="line-42"></span><p class="line867"> <h2 id="Unresolved_issues">Unresolved issues</h2> <span class="anchor" id="line-43"></span><span class="anchor" id="line-44"></span><p class="line867"><hr /><p class="line874"> <span class="anchor" id="line-45"></span><a href="/CategorySpec">CategorySpec</a> <span class="anchor" id="line-46"></span><span class="anchor" id="bottom"></span></div>  <div id="pagebottom"></div> </div> <div class="entry-utility"> <span class="cat-links"> <p id="pageinfo" class="info" lang="en" dir="ltr">Oneiric/SoftwareRaid (last edited 2011-05-19 22:45:15 by <span title="??? @ cpe-76-94-215-209.socal.res.rr.com[76.94.215.209]">cpe-76-94-215-209</span>)</p> </span> </div> </div> </div> </div> <div class="clearBoth"></div> </div> </div> <div id="footer"> <div id="siteinfo"> <p> The material on this wiki is available under a free license, see <a href="https://help.ubuntu.com/community/License">Copyright / License</a> for details. </p> </div> </div> <script> (function(i,s,o,g,r,a,m){ i['GoogleAnalyticsObject']=r;i[r]=i[r]||function(){(i[r].q=i[r].q||[]).push(arguments)},i[r].l=1*new Date();a=s.createElement(o),m=s.getElementsByTagName(o)[0];a.async=1;a.src=g;m.parentNode.insertBefore(a,m) })(window,document,'script','//www.google-analytics.com/analytics.js','ga'); ga('create', 'UA-1018242-7', 'auto'); ga('send', 'pageview'); </script></body> </html>