Unlike managed VPS plans, unmanaged VPS plans are not actively managed by A2 Hosting. Unmanaged VPS plans are for more advanced users who are comfortable using the command-line interface and doing system administration tasks. These plans include root account access so you can customize the server as much as necessary. As a result, you are responsible for the following items:
A couple of years ago I remembered going to a demo and watching Hyper-V crash, but since then a lot has changed. Hyper-V can now do many of the same things most enterprise virtualization software boast about. Live migration, HA, templates, and importing VMs from VMware and EC2 using SystemCenter VMM. The only real hang up is the lack of popularity with the Linux community
Every cloud vps plan is housed on redundant solid state drive (SSD) arrays using dependable hardware, and over 18 years of web hosting knowledge. We offer VPS, or virtual private server, solutions for Windows and Linux users alike, and strive to provide quality products and exceptional support. If you’re interested in VPS hosting for your organization, our unmanaged cloud vps plans have got you covered.
 – Error-proof sandbox – Virtual private servers give you “do-over” potential because they exist within a virtual sandbox. Damaging a virtual server won’t impact the operating system running on the hardware itself. “The VPS can be rebooted or reinstalled without much issue except maybe for lost data (so always keep backups),” notes Joel Lee of MakeUseOf. “On a dedicated host, a mistake could cause permanent damage.”

VPS has a dedicated IP address, which you do not have to share with other users. This is important, as in shared hosting many domains are under one IP address and if one website fails, the whole IP address is added to the blacklist. Also, in case of shared hosting, your website's load can be affected by another user on the same server. It means that if your "neighbor" website is loading or it is inaccessible for various reasons, your website loading time can be increased too.

Partitioning a single server to appear as multiple servers has been increasingly common on microcomputers since the launch of VMware ESX Server in 2001. The physical server typically runs a hypervisor which is tasked with creating, releasing, and managing the resources of "guest" operating systems, or virtual machines. These guest operating systems are allocated a share of resources of the physical server, typically in a manner in which the guest is not aware of any other physical resources save for those allocated to it by the hypervisor. As a VPS runs its own copy of its operating system, customers have superuser-level access to that operating system instance, and can install almost any software that runs on the OS; however, due to the number of virtualization clients typically running on a single machine, a VPS generally has limited processor time, RAM, and disk space.[2]