XCP-ng
    • Categories
    • Recent
    • Tags
    • Popular
    • Users
    • Groups
    • Register
    • Login

    Latest Centos 6 kernel not booting.

    Scheduled Pinned Locked Moved Compute
    12 Posts 4 Posters 2.3k Views 1 Watching
    Loading More Posts
    • Oldest to Newest
    • Newest to Oldest
    • Most Votes
    Reply
    • Reply as topic
    Log in to reply
    This topic has been deleted. Only users with topic management privileges can see it.
    • R Offline
      r1 XCP-ng Team
      last edited by

      You can change the VM type to HVM and it will boot fine. Do you have any particular reason to run it in PV?

      K 1 Reply Last reply Reply Quote 0
      • K Offline
        KFC-Netearth
        last edited by

        Thanks for the info. but I have booted this VM on kernel 6.32-754.2.1 and all since then.
        I'll try setting eagerfpu=off

        1 Reply Last reply Reply Quote 0
        • K Offline
          KFC-Netearth @r1
          last edited by

          @r1 Thanks - I'll try that, its a PV because that's how it was created by default back in 2012.

          1 Reply Last reply Reply Quote 0
          • K Offline
            KFC-Netearth
            last edited by

            Well eagerfpu=off makes no difference and converting to a HVM brings up the grub boot menu but the new kernel shuts down like before and the other kernels just hang, so the VM is now completely unbootable.
            I'll try to convert back to a PV.
            If that doesn't work, I have a pre-convert copy to boot from.

            1 Reply Last reply Reply Quote 0
            • R Offline
              r1 XCP-ng Team
              last edited by

              Remove quite rhgb spalsh from kernel command line and add noreboot to see why its faulting.

              1 Reply Last reply Reply Quote 0
              • olivierlambertO Offline
                olivierlambert Vates 🪐 Co-Founder CEO
                last edited by

                In general, I would suggest to go for HVM mode instead of PV.

                1 Reply Last reply Reply Quote 0
                • K Offline
                  KFC-Netearth
                  last edited by

                  Converting back ti PV allow be to boot the old kernel again:
                  2.6.32-754.23.1.el6.centos.plus.x86_64

                  I'll change the new kernel command from:

                  kernel /vmlinuz-2.6.32-754.24.2.el6.centos.plus.x86_64 ro root=/dev/mapper/VolGroup-lv_root rd_NO_LUKS LANG=en_US.UTF-8 rd_NO_MD console=hvc0  KEYTABLE=us rd_LVM_LV=VolGroup/lv_swap SYSFONT=latarcyrheb-sun16 rhgb crashkernel=auto quiet  rd_LVM_LV=VolGroup/lv_root rd_NO_DM

                  to

                  kernel /vmlinuz-2.6.32-754.24.2.el6.centos.plus.x86_64 ro root=/dev/mapper/VolGroup-lv_root rd_NO_LUKS LANG=en_US.UTF-8 rd_NO_MD console=hvc0  KEYTABLE=us rd_LVM_LV=VolGroup/lv_swap SYSFONT=latarcyrheb-sun16 crashkernel=auto noreboot  rd_LVM_LV=VolGroup/lv_root rd_NO_DM

                  In PV mode all kernels shut down before the console appears.
                  IN HNV mode the new kernel displays:
                  Probing edd=off to disable
                  then shuts down after a few seconds and the older kernels shut down with just a blank screen.
                  Adding eff=off to the kernel line stops "Probing edd=off to disable"
                  appearing but the boot stops as before.

                  Maybe I'll try another Centos 6 VM to see if it does the same or if its just a problem with this VM.

                  1 Reply Last reply Reply Quote 0
                  • R Offline
                    r1 XCP-ng Team
                    last edited by

                    Your new kernel's initrd is missing Xen drivers. You will need to boot on a working kernel and then you can add those using # dracut --add-drivers "xen-blkfront xen-netfront" --kver 2.6.32-754.24.2.el6.centos.plus.x86_64 I'm not sure on 2.6.32-754.24.2.el6.centos.plus.x86_64 string but I guess it should work, else share # ll -ht /boot/.

                    HVM is always recommended than PV.. it will give you noticeable performance improvement.

                    1 Reply Last reply Reply Quote 0
                    • K Offline
                      KFC-Netearth
                      last edited by

                      Yes that's it - thank you 🙂

                      I should have noticed the initramfs line was missing in grub.conf.
                      Strange, for some reason the new kernel install did not create a new initramfs file in /boot.
                      I've just updated an old Centos 6 PV VM and the kernel update creates the new initramfs file and boots the new kernel OK.
                      Maybe I'll remove the new kernel on the bad VM and install it again as there may be other problems with it.
                      The other 4 VMs I updated this morning have a initramfs file for the new kernel.

                      And I'll try HVM mode 🙂

                      R 1 Reply Last reply Reply Quote 0
                      • R Offline
                        r1 XCP-ng Team @KFC-Netearth
                        last edited by

                        @KFC-Netearth Welcome 🙂

                        1 Reply Last reply Reply Quote 0
                        • A Andrew referenced this topic on
                        • First post
                          Last post