====== Xen: PV CentOS не работает ======

Будьте осторожные при обновлении CentOS до релиза 7.4 (1708) с ядром 3.10.0-693 в виртуальной среде Xen PV. В Xen HVM проблемы нет.

  * [[https://plone.lucidsolutions.co.nz/linux/xen/centos/workaround-for-centos-7-with-grub2-and-xen-dom0-with-pv-grub/view|Workaround for CentOS 7 Xen VM with grub2 and Xen dom0 with pv-grub]]
  * [[https://plone.lucidsolutions.co.nz/linux/centos/7/install-centos-plus-kernel-kernel-plus/view|Install CentOS Plus kernel (kernel-plus)]]
  * [[https://srkykzm.com/2015/01/linode-migrate-to-pv-grub/|Migrate pv-grub on Linode VPS]]
  * [[https://www.bfccomputing.com/2017/09/15/centos-plus-kernel-for-xen.html|CentOS Plus Kernel for Xen]]
  * [[https://prgmr.com/blog/2017/09/14/centos-7-pv-unsupported.html|Upgrade with caution: CentOS 7.4 (1708) does not support PV]]

<panel type="danger" title="CentOS-7 (1708) Release Notes">
If you are running CentOS-7 as a Xen domU in ParaVirtualization (PV) mode, an upgrade to CentOS-7 (1708) will cause the VM to not be able to boot. You must use HVM (full emulation) or PV-on-HVM mode to run this version of CentOS with the Xen hypervisor. Please see this mailing list thread for more details.
</panel>

Осталось попробовать заменить grub2 на grub-legacy https://lists.centos.org/pipermail/centos/2015-August/154261.html

Yeah just yum erase grub2 and then force the installation of the
CentOS 6 grub package; then run grub-install.