<html><body><div style="font-family: garamond,new york,times,serif; font-size: 12pt; color: #000000"><div><br></div><div><br></div><hr id="zwchr"><blockquote style="border-left:2px solid #1010FF;margin-left:5px;padding-left:5px;color:#000;font-weight:normal;font-style:normal;text-decoration:none;font-family:Helvetica,Arial,sans-serif;font-size:12pt;" data-mce-style="border-left: 2px solid #1010FF; margin-left: 5px; padding-left: 5px; color: #000; font-weight: normal; font-style: normal; text-decoration: none; font-family: Helvetica,Arial,sans-serif; font-size: 12pt;"><b>From: </b>"Bharathram Sivasubramanian" <Bharathram.Sivasubramanian@vantrix.com><br><b>To: </b>Gluster-users@gluster.org<br><b>Sent: </b>Saturday, April 11, 2015 3:03:48 AM<br><b>Subject: </b>[Gluster-users] Question on file reads from a distributed replicated volume<br><div><br></div><style><!--
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--></style><div class="WordSection1"><p class="MsoNormal">Let us assume that we have a distributed replicated gluster volume with 4 bricks. Brick 1 is replicating its data with Brick 2 and Brick 3 is replicating its data with Brick 4. Suppose a file called aa.txt is present and replicated on Bricks 1 & 2. A gluster client would like to read this file. Which brick will the file come from? In other words:</p><p class="MsoListParagraph" style="text-indent:-18.0pt;mso-list:l0 level1 lfo1" data-mce-style="text-indent: -18.0pt; mso-list: l0 level1 lfo1;"><span style="mso-list:Ignore" data-mce-style="mso-list: Ignore;">-<span style="font:7.0pt "Times New Roman"" data-mce-style="font: 7.0pt 'Times New Roman';"> </span></span>Will the file always be fetched from brick 1?</p><p class="MsoListParagraph" style="text-indent:-18.0pt;mso-list:l0 level1 lfo1" data-mce-style="text-indent: -18.0pt; mso-list: l0 level1 lfo1;"><span style="mso-list:Ignore" data-mce-style="mso-list: Ignore;">-<span style="font:7.0pt "Times New Roman"" data-mce-style="font: 7.0pt 'Times New Roman';"> </span></span>Will the file always be fetched from brick 2?</p><p class="MsoListParagraph" style="text-indent:-18.0pt;mso-list:l0 level1 lfo1" data-mce-style="text-indent: -18.0pt; mso-list: l0 level1 lfo1;"><span style="mso-list:Ignore" data-mce-style="mso-list: Ignore;">-<span style="font:7.0pt "Times New Roman"" data-mce-style="font: 7.0pt 'Times New Roman';"> </span></span>Will the file be fetched from brick 1 or 2 depending on the attempt? i.e. is there some load balancing where sometimes the file comes from brick 1 and at other times the file will come from brick 2?</p></div></blockquote><div>A given file will consistently be "read" from one of the N (in this case 2) replicas, as long as it holds a good copy of the file (that which does not need heal), even with client restart. We call it the "read child" of the file. <span style="font-size: 12pt;">Load balancing within a volume is done across different files wherein different files would have different but constant read children.</span></div><div><span style="font-size: 12pt;"><br></span></div><div><span style="font-size: 12pt;">-Krutika</span></div><blockquote style="border-left:2px solid #1010FF;margin-left:5px;padding-left:5px;color:#000;font-weight:normal;font-style:normal;text-decoration:none;font-family:Helvetica,Arial,sans-serif;font-size:12pt;" data-mce-style="border-left: 2px solid #1010FF; margin-left: 5px; padding-left: 5px; color: #000; font-weight: normal; font-style: normal; text-decoration: none; font-family: Helvetica,Arial,sans-serif; font-size: 12pt;">_______________________________________________<br>Gluster-users mailing list<br>Gluster-users@gluster.org<br>http://www.gluster.org/mailman/listinfo/gluster-users</blockquote><div><br></div></div></body></html>