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</o:shapelayout></xml><![endif]--></head><body lang=EN-GB link="#0563C1" vlink="#954F72"><div class=WordSection1><p class=MsoPlainText><span style='font-size:10.0pt;font-family:"Verdana","sans-serif"'>Hi Lew<o:p></o:p></span></p><p class=MsoPlainText><span style='font-size:10.0pt;font-family:"Verdana","sans-serif"'><o:p> </o:p></span></p><p class=MsoPlainText><span style='font-size:10.0pt;font-family:"Verdana","sans-serif"'>I run 6 different Linux hosts on Hyper-V. It works fine if you know what to do.<o:p></o:p></span></p><p class=MsoPlainText><span style='font-size:10.0pt;font-family:"Verdana","sans-serif"'><o:p> </o:p></span></p><p class=MsoPlainText><span style='font-size:10.0pt;font-family:"Verdana","sans-serif"'>Don’t panic. I think I know what this is.<o:p></o:p></span></p><p class=MsoPlainText><span style='font-size:10.0pt;font-family:"Verdana","sans-serif"'><o:p> </o:p></span></p><p class=MsoPlainText><span style='font-size:10.0pt;font-family:"Verdana","sans-serif"'>As you are virtualised using Hyper-V and you recently did a yum update. The new kernel cannot see your disks properly.<o:p></o:p></span></p><p class=MsoPlainText><span style='font-size:10.0pt;font-family:"Verdana","sans-serif"'><o:p> </o:p></span></p><p class=MsoPlainText><span style='font-size:10.0pt;font-family:"Verdana","sans-serif"'>The quick fix is to reboot, hit a key to get to the boot menu and select an earlier kernel.<o:p></o:p></span></p><p class=MsoPlainText><span style='font-size:10.0pt;font-family:"Verdana","sans-serif"'><o:p> </o:p></span></p><p class=MsoPlainText><span style='font-size:10.0pt;font-family:"Verdana","sans-serif"'>The next fix is to edit both:<o:p></o:p></span></p><p class=MsoPlainText><span style='font-size:10.0pt;font-family:"Verdana","sans-serif"'><o:p> </o:p></span></p><p class=MsoPlainText><span style='font-size:10.0pt;font-family:"Verdana","sans-serif"'>/boot/grub/grub.conf<o:p></o:p></span></p><p class=MsoPlainText><span style='font-size:10.0pt;font-family:"Verdana","sans-serif"'>/etc/grub.conf <o:p></o:p></span></p><p class=MsoPlainText><span style='font-size:10.0pt;font-family:"Verdana","sans-serif"'><o:p> </o:p></span></p><p class=MsoPlainText><span style='font-size:10.0pt;font-family:"Verdana","sans-serif"'>And make the working kernel the default.<o:p></o:p></span></p><p class=MsoPlainText><span style='font-size:10.0pt;font-family:"Verdana","sans-serif"'><o:p> </o:p></span></p><p class=MsoPlainText><span style='font-size:10.0pt;font-family:"Verdana","sans-serif"'>Then once you are stable look at post 11567 and 11643 in this list for the way to make the new kernel behave.<o:p></o:p></span></p><p class=MsoPlainText><span style='font-size:10.0pt;font-family:"Verdana","sans-serif"'><o:p> </o:p></span></p><p class=MsoPlainText><span style='font-size:10.0pt;font-family:"Verdana","sans-serif"'>However I wouldn’t bother with this last bit as there is better news:<o:p></o:p></span></p><p class=MsoPlainText><span style='font-size:10.0pt;font-family:"Verdana","sans-serif"'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Verdana","sans-serif";color:#0D0D0D'>Already released Kernel 5.9 (and 6.4 which is due out any day) has proper built in support for Hyper-V<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Verdana","sans-serif";color:#0D0D0D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Verdana","sans-serif";color:#0D0D0D'>So wait for 6.4 and then all you need to do is:<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Verdana","sans-serif";color:#0D0D0D'><o:p> </o:p></span></p><p class=MsoNormal style='margin-left:36.0pt'><span style='font-size:10.0pt;font-family:"Verdana","sans-serif";color:#0D0D0D'>Boot into the old kernel<o:p></o:p></span></p><p class=MsoNormal style='margin-left:36.0pt'><span style='font-size:10.0pt;font-family:"Verdana","sans-serif";color:#0D0D0D'>Remove the old Hyper-V components as follows:<o:p></o:p></span></p><p class=MsoNormal style='margin-left:36.0pt'><span style='font-size:10.0pt;font-family:"Verdana","sans-serif";color:#0D0D0D'><o:p> </o:p></span></p><p class=MsoNormal style='margin-left:72.0pt'><i><span style='font-size:10.0pt;font-family:"Verdana","sans-serif";color:#0D0D0D'>Execute the following steps in the bash shell.<o:p></o:p></span></i></p><p class=MsoNormal style='margin-left:72.0pt'><i><span style='font-size:10.0pt;font-family:"Verdana","sans-serif";color:#0D0D0D'>1. First, execute:<o:p></o:p></span></i></p><p class=MsoNormal style='margin-left:72.0pt'><b><i><span style='font-size:10.0pt;font-family:"Verdana","sans-serif";color:#0D0D0D'>rpm –qa | grep microsoft<o:p></o:p></span></i></b></p><p class=MsoNormal style='margin-left:108.0pt'><i><span style='font-size:10.0pt;font-family:"Verdana","sans-serif";color:#0D0D0D'>Example:<o:p></o:p></span></i></p><p class=MsoNormal style='margin-left:108.0pt'><i><span style='font-size:10.0pt;font-family:"Verdana","sans-serif";color:#0D0D0D'>On a RHEL 5.8 system, you will see the following:<o:p></o:p></span></i></p><p class=MsoNormal style='margin-left:108.0pt'><i><span style='font-size:10.0pt;font-family:"Verdana","sans-serif";color:#0D0D0D'># rpm –qa | grep microsoft<o:p></o:p></span></i></p><p class=MsoNormal style='margin-left:108.0pt'><i><span style='font-size:10.0pt;font-family:"Verdana","sans-serif";color:#0D0D0D'>kmod-microsoft-hyper-v-3.4-1.20120727<o:p></o:p></span></i></p><p class=MsoNormal style='margin-left:108.0pt'><i><span style='font-size:10.0pt;font-family:"Verdana","sans-serif";color:#0D0D0D'>microsoft-hyper-v-3.4.20120727<o:p></o:p></span></i></p><p class=MsoNormal style='margin-left:72.0pt'><i><span style='font-size:10.0pt;font-family:"Verdana","sans-serif";color:#0D0D0D'>2. Next, execute:<o:p></o:p></span></i></p><p class=MsoNormal style='margin-left:72.0pt'><b><i><span style='font-size:10.0pt;font-family:"Verdana","sans-serif";color:#0D0D0D'>rpm –e microsoft-hyper-v-</span></i></b><i><span style='font-size:10.0pt;font-family:"Verdana","sans-serif";color:#0D0D0D'><version string from step 1> <b>kmod-microsoft-hyper-v-</b><version string from step 1><o:p></o:p></span></i></p><p class=MsoNormal><b><i><span style='font-size:10.0pt;font-family:"Verdana","sans-serif";color:#0D0D0D'><o:p> </o:p></span></i></b></p><p class=MsoNormal><b><i><span style='font-size:10.0pt;font-family:"Verdana","sans-serif";color:#0D0D0D'> </span></i></b><span style='font-size:10.0pt;font-family:"Verdana","sans-serif";color:#0D0D0D'>Then reboot into the new kernel<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Verdana","sans-serif";color:#0D0D0D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Verdana","sans-serif";color:#0D0D0D'>You can then add a NON-LEGACY network card and have a nuch faster network stack. Give the new card the same Virtual MAC as the old card and there are no config changes needed either.<o:p></o:p></span></p><p class=MsoPlainText><span style='font-size:10.0pt;font-family:"Verdana","sans-serif"'><o:p> </o:p></span></p><p class=MsoPlainText><b><span style='font-size:10.0pt;font-family:"Verdana","sans-serif"'>Jason Ozin<o:p></o:p></span></b></p><p class=MsoPlainText><o:p> </o:p></p></div></body></html>