Virtualization

Correct Answer: Implement thin provisioning

The best way a network administrator can decrease storage space consumption in a virtual environment is to 'Implement thin provisioning'. Thin provisioning is a method of storage allocation providing space on a flexible just-on-time basis rather than preallocating to each virtual machine (VM). It effectively optimizes the utilization of available space, resulting in significant savings in storage costs. 'Allocate maximum storage capacity to all VMs' is incorrect because it increases rather than decreases storage space consumption. It also results in waste of storage space that could be used by other VMs. 'Store VM images on local host storage' is also wrong because it does not necessarily decrease the storage space consumption in the virtual environment, it just displaces the storage to a different storage system. 'Enable full duplex mode on virtual switches' is not relevant to the storage space consumption as it pertains to network data transmission and not storage.

Correct Answer: CPU overcommitment

CPU overcommitment should be implemented to optimize CPU usage for the new VMs. CPU overcommitment allows the hypervisor to allocate more virtual CPUs to the VMs than there are physical CPU cores available on the host. This enables the VMs to share the physical CPU resources efficiently, as most VMs do not utilize 100% of their allocated CPU all the time. Memory ballooning is used to optimize memory usage, not CPU. Disk thin provisioning is used to optimize storage allocation. Nested virtualization allows running a hypervisor inside a virtual machine, which is not directly related to optimizing CPU usage on the host.

Correct Answer: Dynamic Resource Scheduling (DRS)

The correct technique to reduce the energy consumption of a company's virtualization infrastructure is Dynamic Resource Scheduling (DRS). DRS is a feature in a virtualized infrastructure that distributes and balances computing workloads evenly across several resources in a virtual environment to ensure that no single resource is overwhelmed. This would result in less energy consumption because resources are not overused. On the other hand, VM high availability is not directly related to energy conservation, it is a method that provides the ability to quickly recover from a VM failure. Virtual LANs (VLANs) are used to segment a network into smaller networks, which does not necessarily yield energy savings. Lastly, Storage I/O control is also not directly related to energy consumption, it's primarily concerned with managing storage input and output to increase efficiency and performance.