What Is Hot Migration?

Hot Migration, also known as "live migration" or "dynamic migration," is the process of moving a virtual machine (VM) from one physical host to another without disrupting the VM's operation. This means the VM can continue to run and provide service to users while it is being moved. Think of it like moving houses, but instead of packing up all your stuff and hauling it to a new place, you're just magically transporting your entire house (or, in this case, VM) to a new location without skipping a beat. Hot Migration is made possible through various technologies such as VMotion and Live Migration. These technologies use a process called "memory page transfer" to move the VM's memory from the source host to the destination host. This allows the VM to continue running on the destination host while the memory is being transferred, resulting in minimal downtime. One of the key benefits of Hot Migration is the ability to perform maintenance on a host without disrupting the VMs running on it. For example, suppose a host needs to be rebooted or updated. In that case, the VMs can be moved to another host, allowing the maintenance to be performed without disrupting the service provided by the VMs. Hot Migration also allows for load balancing between hosts. If one host runs at capacity and another has spare resources, VMs can be moved from the busy host to the less active host to balance the load. This ensures that VMs have the resources they need to run smoothly and can help prevent performance issues. In addition, Hot Migration can also be used for disaster recovery. If a host fails, its VMs can be quickly moved to another host to ensure that service is not disrupted. Overall, Hot Migration is a potent tool for managing virtualized environments. It allows for easy maintenance, load balancing, and disaster recovery, all while keeping VMs running smoothly and providing service to users. So, next time you're moving a virtual machine, remember it's like moving house but with a lot less stress and magic!