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</o:shapelayout></xml><![endif]--></head><body lang=DE-CH link="#0563C1" vlink="#954F72"><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;mso-fareast-language:EN-US'>Hi,<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;mso-fareast-language:EN-US'>to me here your question confuses a bit. About what RAID you talk about? RAID0, RAID1 or RAID5? With RAID0 you have twice read performance in best case. But DRBD does RAID1 over TCP/IP what means mirroring two disk/disk set. If one fails the other one comes into operation.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;mso-fareast-language:EN-US'>Next I don’t understand, when you got iSCSI then you don’t need DRBD! In my mind iSCSI devices are all connected to the same host, here what you need is “mount”.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;mso-fareast-language:EN-US'>DRBD usually you will need to implement RAID1 with two separate hosts, to become hardware redundanty over TCP/IP. If that is what you need, then yes, DRBD can do this.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;mso-fareast-language:EN-US'>Thanks, Walter<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><b><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif"'>From:</span></b><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif"'> drbd-user-bounces@lists.linbit.com [mailto:drbd-user-bounces@lists.linbit.com] <b>On Behalf Of </b>ml ml<br><b>Sent:</b> Sonntag, 25. August 2013 14:36<br><b>To:</b> drbd-user@lists.linbit.com<br><b>Subject:</b> [DRBD-user] Raid1/Drbd read performance<o:p></o:p></span></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Hello list!<o:p></o:p></p><div><p class=MsoNormal>I am using xen with drbd which is attached to two iscsi targets.<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>On normal hardware raid controllers the read is done from two disks ( so u get about twice the read performance).<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Does Drbd support this? (reading from secondary over the network)<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Thanks,<o:p></o:p></p></div><div><p class=MsoNormal>Mario<o:p></o:p></p></div></div></body></html>