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</o:shapelayout></xml><![endif]--></head><body lang=FR link="#0563C1" vlink="#954F72"><div class=WordSection1><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'>Hi Antonio !<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'>As far as I know, virtio is the IO layer of KVM. In your case you’re planning to use ESXi, so I believe you may disregard that point.<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'>However, as Cesar said, performance will be key. So take care to implement the most performant paravirtualized drivers within your VMs, namely vmxnet3 and pvscsi (But if your distro is recent, that will the case by default), and it probably would also be a good idea to put your replication network on dedicated vSwitch, with dedicated vmnics, to avoid bandwidth sharing.<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'>There’s also a feature within ESXi that’s called “VM Direct Path IO”, I think it’s standard, you don’t have to pay for it, that consists of dedicating a piece of hardware to some VM, might be a card, a port... In this case, you have to install the corresponding driver into the guest OS, and you forget vmxnet3, at least for this replication link(s). There are 2 advantages : 1) You ensure bandwidth dedication to these VMs 2) You avoid VMkernel virtualization overhead. This maximizes performances. I know Telco guys that used that with 10GbE cards to achieve their perf requirements. If you use that however, your VM will be tied to its ESXi, you won’t be able to migrate it on another host, but from the DRBD prospective, I don’t guess it’s a big deal for your clustering is “at the DRBD level” if I may say…<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'>Hope this helps!<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'>Best regards,<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'>Pascal.<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><b><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>De :</span></b><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'> drbd-user-bounces@lists.linbit.com [mailto:drbd-user-bounces@lists.linbit.com] <b>De la part de</b> Antonio Fernández Pérez<br><b>Envoyé :</b> mercredi 18 février 2015 11:20<br><b>À :</b> Cesar Peschiera<br><b>Cc :</b> drbd-user@lists.linbit.com<br><b>Objet :</b> Re: [DRBD-user] DRBD on virtual machine<o:p></o:p></span></p><p class=MsoNormal><o:p> </o:p></p><div><div><div><p class=MsoNormal><span style='color:#444444'>Hi list:</span><o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal><span style='color:#444444'>Thanks for your replies.</span><o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal><span style='color:#444444'>I will have MySQL on these two servers. On our environment there are a lot of read/write transactions so speed is very important for perform everyday actions.</span><o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal><span style='color:#444444'>I don't understand when you say about virtio-block and virtio-net. What is that? Some configuration method for VM?</span><o:p></o:p></p></div><div><p class=MsoNormal><span style='color:#444444'>What do you want to say when you speak about host and guest? I think that an iESX has a lot of VM and a VM is a ¿guest? What is the "host"?</span><o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal><span style='color:#444444'>Thanks for your suggestions.</span><o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal><span style='color:#444444'>Thanks in advance.</span><o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal><span style='color:#444444'>Regards,</span><o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal><span style='color:#444444'>Antonio.</span><o:p></o:p></p></div></div></div></div>
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