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</o:shapelayout></xml><![endif]--></head><body lang=DE link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Thanks!<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Unfortunately the md5sums don’t match... but the sizes & timestamps do. <o:p></o:p></span></p><p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>These binary files from VMs are quite difficult to work with. That’s why I was after some ideas WHICH file should be preferred.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> I’m actually quite concerned how on earth do we trigger “split brain” conditions on a regular basis. <o:p></o:p></span></p><p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Are there any good “DON’Ts” for server updates/maintenance? The current way is shutting down one server , upgrading/installing it, bringing up the Gluster daemons (server & client)/mounting the file system, checking everything is running. Then starting on the next server. <o:p></o:p></span></p><p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>So a pure sequential approach. Thought this would minimise the risk of getting the files in a twist?!?<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Best, Martin<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0cm 0cm 0cm'><p class=MsoNormal><b><span lang=EN-US style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>From:</span></b><span lang=EN-US style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'> Anand Avati [mailto:anand.avati@gmail.com] <br><b>Sent:</b> Wednesday, May 04, 2011 2:55 PM<br><b>To:</b> Martin Schenker<br><b>Cc:</b> gluster-users@gluster.org<br><b>Subject:</b> Re: [Gluster-users] Split brain; which file to choose for repair?<o:p></o:p></span></p></div><p class=MsoNormal><span lang=EN-GB><o:p> </o:p></span></p><p class=MsoNormal>Occurance of a split brain situation is only under a specific sequence of events and modifications and the filesystem cannot decide which of the two copies of the file is updated. It might so happen that the two changes were actually the same "change" and hence the two copies of your file might match md5sum (in which case you can delete one arbitrarily). If not, you need to know how your application works and which of the file (inspecting the content) is more appropriate to be deleted.<o:p></o:p></p><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal style='margin-bottom:12.0pt'>Avati<o:p></o:p></p><div><p class=MsoNormal>On Wed, May 4, 2011 at 5:54 PM, Martin Schenker <<a href="mailto:martin.schenker@profitbricks.com">martin.schenker@profitbricks.com</a>> wrote:<o:p></o:p></p><p class=MsoNormal>Hi all!<br><br>Is there anybody who can give some pointers regarding which file to choose<br>in a "split brain" condition?<br><br>What tests do I need to run?<br><br>What does the hex AFR code actually show? Is there a way to pinpoint the<br>"better/worse" file for deletion?<br><br>On pserver12:<o:p></o:p></p><div><p class=MsoNormal style='margin-bottom:12.0pt'><br># file: mnt/gluster/brick0/storage/pserver3-19<br>trusted.afr.storage0-client-5=0x3f0000010000000000000000<o:p></o:p></p></div><p class=MsoNormal>On pserver13:<o:p></o:p></p><div><p class=MsoNormal style='margin-bottom:12.0pt'><br># file: mnt/gluster/brick0/storage/pserver3-19<br>trusted.afr.storage0-client-4=0xd70000010000000000000000<o:p></o:p></p></div><p class=MsoNormal>These are test files, but I'd like to know what to do in a LIFE situation<br>which will be just around the corner.<br><br>The Timestamps show the same values, so I'm a bit puzzled HOW to choose a<br>file.<br><br>pserver12:<br><br>0 root@de-dc1-c1-pserver12:~ # ls -al<br>/mnt/gluster/brick0/storage/pserver3-19<br>-rw-r--r-- 1 vcb root 3456106496 Apr 29 17:40<br>/mnt/gluster/brick0/storage/pserver3-19<br><br>0 root@de-dc1-c1-pserver12:~ # ls -alu<br>/mnt/gluster/brick0/storage/pserver3-19<br>-rw-r--r-- 1 vcb root 3456106496 Apr 28 16:18<br>/mnt/gluster/brick0/storage/pserver3-19<br><br>pserver13:<br><br>0 root@de-dc1-c1-pserver13:~ # ls -al<br>/mnt/gluster/brick0/storage/pserver3-19<br>-rw-r--r-- 1 vcb root 3456106496 Apr 29 17:40<br>/mnt/gluster/brick0/storage/pserver3-19<br><br>0 root@de-dc1-c1-pserver13:~ # ls -alu<br>/mnt/gluster/brick0/storage/pserver3-19<br>-rw-r--r-- 1 vcb root 3456106496 Apr 28 16:18<br>/mnt/gluster/brick0/storage/pserver3-19<br><br>Best, Martin<o:p></o:p></p><div><div><p class=MsoNormal><br>_______________________________________________<br>Gluster-users mailing list<br><a href="mailto:Gluster-users@gluster.org">Gluster-users@gluster.org</a><br><a href="http://gluster.org/cgi-bin/mailman/listinfo/gluster-users" target="_blank">http://gluster.org/cgi-bin/mailman/listinfo/gluster-users</a><o:p></o:p></p></div></div></div><p class=MsoNormal><o:p> </o:p></p></div></div></body></html>