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When moving a KVM image to another server, it’s a pretty simple process. If you’re using SolusVM or Virtualizor, it makes it even easier. However, if you have a VM node which hosts openVZ containers and need to move them to a new node with different virtualization, QEMU/KVM in this case, it makes things a little more difficult. The main different between KVM and openVZ is the level of virtualization. OpenVZ is an OS level virtualization which means the hosts’ kernel is shared with guest containers inside it, you can’t use your own kernel. KVM is very different. It’s a full virtualization. The whole OS and its kernel is virtualized so you can even install an OS with its own kernel in it, like installing Windows VM inside a linux host. So let’s get on with this tutorial now that we have a little background. Please proceed at your own risk! – Converting OpenVZ to KVM box Let’s start the moving process. 1. The first step before start moving the box is installing a KVM box with the exact same OS as the openVZ container, preferably same point revision too (You will want to run yum update on both VM’s to make sure) 2. SSH into both VMs. 3. In the KVM box, or openVZ box, install mingetty. I’m using CentOS 6.2 so I use yum to install mingetty yum install mingetty 4. Edit /etc/inittab in the VM installed with mingetty vi /etc/inittab and add these lines # Run gettys in standard run levels 1:2345:respawn:/sbin/mingetty tty1 2:2345:respawn:/sbin/mingetty tty2 3:2345:respawn:/sbin/mingetty tty3 4:2345:respawn:/sbin/mingetty tty4 5:2345:respawn:/sbin/mingetty tty5 6:2345:respawn:/sbin/mingetty tty6 This will enable the machine to actually get a logon prompt. 5. Install rsync on both VMs yum install rsync 6. From the openVZ box, make a text file containing files to exclude. This will preserve settings in KVM box to make sure the VM is bootable. nano /root/exclude.txt add these lines to exclude.txt, you may customize it to your needs /boot /proc /sys /tmp /dev /var/lock /etc/fstab /etc/mtab /etc/resolv.conf /etc/conf.d/net /etc/network/interfaces /etc/networks /etc/sysconfig/network* /etc/sysconfig/hwconf /etc/sysconfig/ip6tables-config /etc/sysconfig/kernel /etc/hostname /etc/HOSTNAME /etc/hosts /etc/modprobe* /etc/modules /net /lib/modules /etc/rc.conf /usr/share/nova-agent* /usr/sbin/nova-agent* /etc/init.d/nova-agent* /etc/ips /etc/ipaddrpool /etc/ips.dnsmaster /etc/resolv.conf /etc/sysconfig/network-scripts/ifcfg-eth0 7. Now we can start to sync the OpenVZ box to the KVM box. In the openVZ box, type: rsync –exclude-from=”/root/exclude.txt” –delete –numeric-ids -avpogtStlHz -e “ssh -p ” / root@ That’s all, to make sure everything’s working, reboot the KVM box when the rsync process has completed. Once your new KVM box is up, you will have to go in there and make the IP changes to cPAnel/WHM, shoutcast, zPanel, or whichever other control panel you’re using. https://blog.webhostpython.com/2015/11/25/how-to-convertmigrate-openvz-vps-to-xenkvm/

wherever i visited it was made quite clear upgrading CentOS 6 to CentOS 7 is not a realistically viable option https://forums.centos.org/viewtopic.php?t=69363 and OVZ6 or otherwise OpenVZ aka Virtuozzo containers lack their kernel so migrating was between hard to not possible. https://www.lowendtalk.com/discussion/149162/migrate-from-virtuozzo-to-xen-or-kvm Well, we are happy to disagree since we managed to do the Virtualization equivalent of Magellan Circumnavigation after a week of hard work: we started with OVZ container running CentOS 6.10 and cPanel / WHM 11.86 with an upgrade blocker due to COS6 being EOL since November 2020. Managed by trial and error to migrate this container to a KVM clone running same CentOS 6.10 and all files cloned 1-1 with rsync. Then we run the magnificent yet underrrated Red Hat upgrade tool in the KVM virtual machine to upgrade to CentOS 7.0.1406 and had to recreate the missing grub2 entries since grub is no more on COS7. From that point onwards we managed to properly yum update to 7.9 and finally to fix cPanel RPM issues and run a full WHM upgrade to 11.94. In short : OVZ COS6 WHM 11.86 -> KVM COS6 WHM 11.86 -> KVM COS7 WHM 1186 -> KVM COS7 WHM 11.94 and are are running now at latest version with functionality surprisingly high if not almost full identical www.forumsandmore.com