Which feature enables the live migration of virtual machines with zero downtime in VMware?

vMotion is a key feature in VMware that facilitates the live migration of virtual machines from one physical host to another without any downtime. This capability is critical for maintaining service availability and uninterrupted operations during maintenance or load balancing tasks. vMotion works by transferring the active memory and system state of the virtual machine over the network while the VM continues to run, allowing users to remain connected to their applications without any interruptions.

The process involves creating a replicated memory state and transferring it to the target host. Once the memory and system information is in sync, the virtual machine is moved to the new host, and its operations continue smoothly as if nothing changed. This capability is an essential part of VMware environments, ensuring high availability and resource optimization.

High Availability does provide fault tolerance by automatically restarting VMs on other hosts in the event of a failure, but it does not offer the capability to move VMs while they are still running. Snapshots allow for capturing the state of a virtual machine at a specific point in time, enabling quick recovery, but they do not facilitate live migration. The Distributed Resource Scheduler (DRS) helps in balancing workloads across hosts but, similar to High Availability, does not perform direct live migrations without downtime.