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<p class="MsoNormal"><span lang="EN-US" style="color:#1F497D">Does it mean that if I use gluster FUSE driver or NFS client, fcntl locks are manages and no data corruption could happen ?<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="color:#1F497D"><o:p> </o:p></span></p>
<div>
<p class="MsoNormal"><b><span style="font-size:10.0pt;font-family:"Arial","sans-serif";color:#1F497D;mso-fareast-language:FR;layout-grid-mode:line">Sébastien Coché,</span></b><span style="font-size:10.0pt;font-family:"Arial","sans-serif";color:#1F497D;mso-fareast-language:FR;layout-grid-mode:line">
<o:p></o:p></span></p>
<p class="MsoNormal" style="margin-top:6.0pt"><span style="font-size:10.0pt;font-family:"Arial","sans-serif";mso-fareast-language:FR">Architecte Infrastructure</span><span style="font-size:10.0pt;font-family:"Arial","sans-serif";color:#1F497D;mso-fareast-language:FR;layout-grid-mode:line">
(DIP)<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial","sans-serif";color:#1F497D;mso-fareast-language:FR;layout-grid-mode:line">SIGMA Informatique –
</span><u><span style="font-size:10.0pt;font-family:"Arial","sans-serif";color:blue;mso-fareast-language:FR;layout-grid-mode:line"><a href="http://www.sigma.fr/">www.sigma.fr</a><o:p></o:p></span></u></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial","sans-serif";mso-fareast-language:FR">8 rue Newton – CS 84533 – 44245 LA CHAPELLE SUR ERDRE CEDEX<o:p></o:p></span></p>
<p class="MsoNormal" style="mso-line-height-alt:0pt"><span style="font-size:10.0pt;font-family:"Arial","sans-serif";color:#1F497D;mso-fareast-language:FR;layout-grid-mode:line">Tél :
</span><span style="font-size:10.0pt;font-family:"Arial","sans-serif";mso-fareast-language:FR">(+33) 2.53.48.92.57</span><span style="font-size:10.0pt;font-family:"Arial","sans-serif";color:#1F497D;mso-fareast-language:FR;layout-grid-mode:line"> – Mob : 06
22 25 03 74</span><span style="font-size:9.0pt;font-family:"Arial","sans-serif";mso-fareast-language:FR"><o:p></o:p></span></p>
</div>
<p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
<div>
<div style="border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0cm 0cm 0cm">
<p class="MsoNormal"><b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";color:windowtext;mso-fareast-language:FR">De :</span></b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";color:windowtext;mso-fareast-language:FR"> Pranith
Kumar Karampuri [mailto:pkarampu@redhat.com] <br>
<b>Envoyé :</b> lundi 30 juin 2014 18:08<br>
<b>À :</b> COCHE Sébastien<br>
<b>Cc :</b> gluster-users@gluster.org<br>
<b>Objet :</b> Re: [Gluster-users] Concurrent writes management.<o:p></o:p></span></p>
</div>
</div>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<div>
<p class="MsoNormal">On 06/30/2014 09:26 PM, COCHE Sébastien wrote:<o:p></o:p></p>
</div>
<blockquote style="margin-top:5.0pt;margin-bottom:5.0pt">
<p class="MsoNormal"><span lang="EN-US" style="color:#1F497D">Thank you for your response.</span><o:p></o:p></p>
<p class="MsoNormal"><span lang="EN-US" style="color:#1F497D">I understand that the file exist only one time on the volume. But it can be accessed in write, by many nodes (clients) at the same time.</span><o:p></o:p></p>
<p class="MsoNormal"><span lang="EN-US" style="color:#1F497D">What’s happen in those case ?</span><o:p></o:p></p>
</blockquote>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Times New Roman","serif";mso-fareast-language:FR">Nothing bad will happen to the filesystem. But the file may not be meaningful if the applications writing to it don't synchronize overlapping concurrent
writes with fcntl locks.<br>
<br>
Pranith <br>
<br>
<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="color:#1F497D"> </span><o:p></o:p></p>
<p class="MsoNormal"><span lang="EN-US" style="color:#1F497D"> </span><o:p></o:p></p>
<div>
<p class="MsoNormal"><b><span style="font-size:10.0pt;font-family:"Arial","sans-serif";color:#1F497D;mso-fareast-language:FR;layout-grid-mode:line">Sébastien Coché,</span></b><o:p></o:p></p>
<p class="MsoNormal" style="margin-top:6.0pt"><span style="font-size:10.0pt;font-family:"Arial","sans-serif";mso-fareast-language:FR">Architecte Infrastructure</span><span style="font-size:10.0pt;font-family:"Arial","sans-serif";color:#1F497D;mso-fareast-language:FR;layout-grid-mode:line">
(DIP)</span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial","sans-serif";color:#1F497D;mso-fareast-language:FR;layout-grid-mode:line">SIGMA Informatique –
</span><u><span style="font-size:10.0pt;font-family:"Arial","sans-serif";color:blue;mso-fareast-language:FR;layout-grid-mode:line"><a href="http://www.sigma.fr/">www.sigma.fr</a></span></u><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial","sans-serif";mso-fareast-language:FR">8 rue Newton – CS 84533 – 44245 LA CHAPELLE SUR ERDRE CEDEX</span><o:p></o:p></p>
<p class="MsoNormal" style="mso-line-height-alt:0pt"><span style="font-size:10.0pt;font-family:"Arial","sans-serif";color:#1F497D;mso-fareast-language:FR;layout-grid-mode:line">Tél :
</span><span style="font-size:10.0pt;font-family:"Arial","sans-serif";mso-fareast-language:FR">(+33) 2.53.48.92.57</span><span style="font-size:10.0pt;font-family:"Arial","sans-serif";color:#1F497D;mso-fareast-language:FR;layout-grid-mode:line"> – Mob : 06
22 25 03 74</span><o:p></o:p></p>
</div>
<p class="MsoNormal"><span style="color:#1F497D"> </span><o:p></o:p></p>
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<div style="border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0cm 0cm 0cm">
<p class="MsoNormal"><b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";color:windowtext;mso-fareast-language:FR">De :</span></b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";color:windowtext;mso-fareast-language:FR"> Pranith
Kumar Karampuri [<a href="mailto:pkarampu@redhat.com">mailto:pkarampu@redhat.com</a>]
<br>
<b>Envoyé :</b> lundi 30 juin 2014 17:49<br>
<b>À :</b> COCHE Sébastien; <a href="mailto:gluster-users@gluster.org">gluster-users@gluster.org</a><br>
<b>Objet :</b> Re: [Gluster-users] Concurrent writes management.</span><o:p></o:p></p>
</div>
</div>
<p class="MsoNormal"> <o:p></o:p></p>
<p class="MsoNormal"> <o:p></o:p></p>
<div>
<p class="MsoNormal">On 06/30/2014 07:49 PM, COCHE Sébastien wrote:<o:p></o:p></p>
</div>
<blockquote style="margin-top:5.0pt;margin-bottom:5.0pt">
<p class="MsoNormal"><span lang="EN-US">Hello</span><o:p></o:p></p>
<p class="MsoNormal"><span lang="EN-US"> </span><o:p></o:p></p>
<p class="MsoNormal"><span lang="EN-US">I have a question regarding concurrent write.</span><o:p></o:p></p>
<p class="MsoNormal"><span lang="EN-US">How are manage those writes ? Is there a risk of data corruption ?</span><o:p></o:p></p>
<p class="MsoNormal"><span lang="EN-US">Is there a lock mechanism, against corruption ? If yes, how it work ?</span><o:p></o:p></p>
<p class="MsoNormal"><span lang="EN-US">I already had a look to forum and documents but I did not found a deep dive explanation.</span><o:p></o:p></p>
</blockquote>
<p class="MsoNormal"><span style="font-size:12.0pt">For plain distribute volumes there exists only one file in the volume with the data. All the operations on the file happen just like they happen on normal filesystem. For replicated/distributed replicated
volumes there are internal locks taken by replication feature to avoid any in-consistencies.<br>
Please check <a href="https://github.com/gluster/glusterfs/blob/master/doc/features/afr-v1.md">
https://github.com/gluster/glusterfs/blob/master/doc/features/afr-v1.md</a> to know more about it.<br>
<br>
Pranith<br>
<br>
<br>
</span><o:p></o:p></p>
<p class="MsoNormal"><span lang="EN-US"> </span><o:p></o:p></p>
<p class="MsoNormal"><span lang="EN-US">Thank for your feedback</span><o:p></o:p></p>
<p class="MsoNormal"><span lang="EN-US">Sorry for my poor english ;-)</span><o:p></o:p></p>
<p class="MsoNormal"><span lang="EN-US"> </span><o:p></o:p></p>
<p class="MsoNormal">Sebastien<o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:12.0pt"><br>
<br>
<br>
<br>
</span><o:p></o:p></p>
<pre>_______________________________________________<o:p></o:p></pre>
<pre>Gluster-users mailing list<o:p></o:p></pre>
<pre><a href="mailto:Gluster-users@gluster.org">Gluster-users@gluster.org</a><o:p></o:p></pre>
<pre><a href="http://supercolony.gluster.org/mailman/listinfo/gluster-users">http://supercolony.gluster.org/mailman/listinfo/gluster-users</a><o:p></o:p></pre>
<p class="MsoNormal"><span style="font-size:12.0pt"> </span><o:p></o:p></p>
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