During a virtual machine migration, which VMkernel networking layer handles the traffic?

In the context of a virtual machine migration, the VMkernel networking layer responsible for handling the traffic is the vSphere vMotion. vSphere vMotion is a VMware technology that enables the live migration of running virtual machines from one physical host to another without downtime. This process allows the virtual machine to continue running smoothly, providing uninterrupted service to users and applications.

During a vMotion operation, the VMkernel handles the entire traffic related to transferring the virtual machine’s RAM, CPU state, and network connections over the network. It optimizes the data path for migration and ensures that the data leaves the source host and is received correctly by the destination host, all while maintaining the VM's operational state.

The other options represent different VMware technologies or functionalities that, while related to virtual environments, do not specifically handle the traffic associated with migrating a VM. For instance, vSAN is focused on storage capabilities, IP storage relates to storage access via IP networks, and Fault Tolerance pertains to maintaining high availability for VMs but does not facilitate migration. Thus, vSphere vMotion is the correct answer as it directly pertains to the management and execution of virtual machine migrations.