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</o:shapelayout></xml><![endif]--></head><body lang=EN-AU link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Customer’s requirements drive the solution, there are many ways to achieve HA storage. I don’t know your exact setup and resources but I reckon iSCSI will be just an unnecessary overhead layer if you are using GlusterFS. You can use DRBD with a clustered file system (e.g. gfs, ocfs, ..) or with xfs/ext3/4 + NFS, you may consider using G/NBD as well. Again, the solution is driven by the customer’s requirements and the available resources. GlusterFS is an awesome solution, provides HA & performance but it has some limited capabilities too, like it doesn’t support POSIX ACL. Lastly my 2cents for a clustered file system, it sounds like a sexy solution but if it’s deployed in a small scale (e.g. < 5 nodes) it might easily become a nightmare. For small scales HA storage without losing stability I’d recommend DRBD + XFS/EXT3/4 + NFS. <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 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"'> linux-cluster-bounces@redhat.com [mailto:linux-cluster-bounces@redhat.com] <b>On Behalf Of </b>chenzp<br><b>Sent:</b> Sunday, 3 April 2011 2:43 PM<br><b>To:</b> linux clustering<br><b>Subject:</b> Re: [Linux-cluster] Replication for iSCSI target?<o:p></o:p></span></p></div><p class=MsoNormal><o:p> </o:p></p><div><p class=MsoNormal>use drbd!<o:p></o:p></p></div><div><p class=MsoNormal><br><br> <o:p></o:p></p></div><div><p class=MsoNormal>2011/4/2 Michael McGlothlin <<a href="mailto:michaelm@plumbersstock.com">michaelm@plumbersstock.com</a>><o:p></o:p></p><p class=MsoNormal>I'm experimenting with setting up an iSCSI target that has data<br>replication between three nodes. Right now I'm trying Glusterfs which<br>seems workable but I'm not sure how it'll handle it if more than one<br>node is trying to access the same target device (1TB sparse file) at<br>the same time. Has anyone set something like this up before and can<br>give me some hints? I was looking at GFS before but it appeared to not<br>do replication? DRBD seemed like a possibility but having more than<br>two nodes sounded as if it might be an issue.<br><br>Each server has dual quad-core Xeon processors, 64GB RAM, 8 2TB<br>drives, and 10Gb Ethernet so I hope hardware won't be a limitation.<br>We've constantly had trouble with every iSCSI, SAN, NAS, etc we've<br>tried so I want to make something that is completely void of any<br>single point of failure.<br><br><br>Thanks,<br>Michael McGlothlin<br><span style='color:#888888'><br>--<br>Linux-cluster mailing list<br><a href="mailto:Linux-cluster@redhat.com">Linux-cluster@redhat.com</a><br><a href="https://www.redhat.com/mailman/listinfo/linux-cluster" target="_blank">https://www.redhat.com/mailman/listinfo/linux-cluster</a></span><o:p></o:p></p></div><p class=MsoNormal><o:p> </o:p></p></div></body></html>