Which resource is able to be shared among virtual machines deployed on the same physical server?

One of the key advantages of virtualization is the ability to share physical resources among multiple virtual machines (VMs) deployed on the same physical server. The resources that can be shared among virtual machines include:

1. CPU (Central Processing Unit)
   Virtualization platforms allow multiple VMs to share the CPU of the physical server. The hypervisor allocates CPU time to each VM, allowing them to run concurrently. CPU scheduling mechanisms ensure fair distribution of processing power among VMs.
2. Memory (RAM)
   Physical memory (RAM) is shared among VMs on a host server. Each VM is allocated a portion of the total physical memory. Memory management features in the hypervisor, such as memory ballooning and page sharing, help optimize memory usage across VMs.
3. Storage
   Virtual machines can share storage resources on the host server. This is often achieved through shared storage devices or shared storage pools. Virtual disks (VMDK in VMware, VHD in Hyper-V, etc.) are created for each VM and stored on shared storage, allowing VMs to access and share data.
4. Network Bandwidth
   Network resources, including bandwidth, can be shared among virtual machines. The hypervisor manages network traffic by providing each VM with virtual network interfaces and controlling the flow of data between VMs and the physical network.
5. I/O Devices
   Input/output (I/O) devices such as network adapters and storage controllers can be shared among virtual machines. Virtual devices are created for each VM, and the hypervisor manages access to the physical I/O devices.
6. GPU (Graphics Processing Unit)
   In virtualized environments that support GPU virtualization, physical GPUs can be shared among multiple VMs. This is particularly useful for applications that require graphical processing capabilities, such as virtual desktop infrastructure (VDI) deployments.
7. Compute Resources
   Beyond CPU and memory, other compute resources such as virtualized hardware extensions (e.g., VT-x for Intel CPUs) and virtualization-assist technologies contribute to the efficient sharing of resources among VMs.

The hypervisor (virtualization layer) plays a crucial role in managing and allocating these shared resources. It abstracts physical hardware, creating a virtualization layer that allows multiple VMs to run independently on the same physical server. Each VM operates as if it has its own dedicated resources, providing isolation and flexibility while efficiently utilizing the underlying hardware.