Analysis of information sources in references of the Wikipedia article "Hipervisor" in Galician language version.
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Rymarczyk watched with interest as VMware adapted the concepts behind IBM's virtualization technology to x86 systems. In some ways, VMware's task was more difficult than IBM's because the Intel and AMD x86 processors used in most corporate data centers were not built with virtualization in mind. With the mainframe, IBM has total control over both the hardware and virtualization software, but VMware had to overcome the idiosyncrasies of x86 hardware developed by other vendors.
Los hipervisores son a los sistemas operativos lo que los sistemas operativos, en cierta medida, son a los procesos, es decir, proveen plataformas de hardware virtual aisladas para ejecución, que, a su vez, dan la ilusión de tener acceso total a la máquina subyacente.
A hypervisor is a type of software that allows multiple operating systems to share a single hardware host.
Los hipervisores se pueden clasificar en dos tipos distintos. Los de tipo 1 son aquéllos que se ejecutan nativamente sobre hardware de metal base. Los de tipo 2, son hipervisores que se ejecutan en el contexto de otro sistema operativo (el cual se ejecuta sobre el metal base). Un ejemplo de hipervisor de tipo 1 es la máquina virtual basada en un núcleo (Kernel-based Virtual Machine – KVM —, que es en sí misma un hipervisor basado en un sistema operativo. Algunos hipervisores de tipo 2 son QEMU y WINE.
Normally virtual machines are encapsulated, isolated environments. The operating systems running inside the virtual machine shouldn’t know that they are virtualized, and there should be no way to break out of the virtual machine and interact with the parent hypervisor. The process of breaking out and interacting with the hypervisor is called a “VM escape.”
A hypervisor is a process that separates a computer’s operating system and applications from the underlying physical hardware. Usually done as software although embedded hypervisors can be created for things like mobile devices. The hypervisor drives the concept of virtualization by allowing the physical host machine to operate multiple virtual machines as guests to help maximize the effective use of computing resources such as memory, network bandwidth and CPU cycles.
The problem of implementing a time-sharing system that would let multiple users access the same computer simultaneously was not an easy one to solve. Most engineers were taking traditional batch operating systems and making them more interactive to let multiple users come into the system, but the operating system itself became extremely complex, Rymarczyk explains. IBM's engineering team in Cambridge, Mass., came up with a novel approach that gave each user a virtual machine (VM), with an operating system that doesn't have to be complex because it only has to support one user, he says.
What was most impressive was how well it worked and how powerful it was," Rymarczyk says. "It let you provide test platforms for software testing and development so that now all of that activity could be done so much more efficiently. It could be interactive too. You could be running a test operating system. When it failed you could look in virtual memory at exactly what was happening. It made debugging and testing much more effective.
The first stake in the ground was CP-40, an operating system for the System/360 mainframe that IBM's Robert Creasy and Les Comeau started developing in 1964 to create VMs within the mainframe.
This hypervisor, also called Virtual Machine Monitor (VMM), creates a virtual platform on the host computer, on top of which multiple guest operating systems are executed and monitored.
A hypervisor is a process that separates a computer’s operating system and applications from the underlying physical hardware. Usually done as software although embedded hypervisors can be created for things like mobile devices. The hypervisor drives the concept of virtualization by allowing the physical host machine to operate multiple virtual machines as guests to help maximize the effective use of computing resources such as memory, network bandwidth and CPU cycles.
Rymarczyk watched with interest as VMware adapted the concepts behind IBM's virtualization technology to x86 systems. In some ways, VMware's task was more difficult than IBM's because the Intel and AMD x86 processors used in most corporate data centers were not built with virtualization in mind. With the mainframe, IBM has total control over both the hardware and virtualization software, but VMware had to overcome the idiosyncrasies of x86 hardware developed by other vendors.
The cause is a widely-ignored, legacy virtual floppy disk controller that, if sent specially crafted code, can crash the entire hypervisor. That can allow a hacker to break out of their own virtual machine to access other machines -- including those owned by other people or companies. The bug, found in open-source computer emulator QEMU, dates back to 2004. Many modern virtualization platforms, including Xen, KVM, and Oracle's VirtualBox, include the buggy code. VMware, Microsoft Hyper-V, and Bochs hypervisors are not affected.
