Virtual machines live migration is a really interesting topic regarding virtualization, since guests continue growing (more CPUs, more RAM) and uptime demands are the same and long pauses between virtual machines migrating from one host to another are not expected.
Reading the article below, you'll learn how to perform a live migration with QEMU/KVM hypervisor. In addition, the post includes interesting information about the early days, present and future of this hypervisor; paying special attention to the updates, optimization and the constant changes required in the design to meet the demands of the community.
Live Migrating QEMU-KVM Virtual Machines

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