What is a KVM virtual machine in Linux

Concept:

Kernel-based virtual Machine is an open source system virtualization module that has been integrated into various major distributions of Linux since Linux 2.6.20. It is managed using Linux's own scheduler, so its core source code is few compared to Xen. KVM has become one of the mainstream VMM in academia today.

KVM Virtualization requires hardware support (such as Intel VT Technology or AMD V technology). is hardware-based full virtualization. The early days of Xen were software-based simulations of para-virtualization, and the new version was full virtualization based on hardware support. But Xen itself has its own process scheduler, storage Management module, etc., so the code is rather large. The widely circulated business system virtualization software VMware ESX series is a software-based simulation of the full-virtualization.

Prerequisites for installing KVM:

1. Confirm that the machine has VT

Terminal input command: grep vmx/proc/cpuinfo (Intel Chip)

grep Svm/proc/cpuinfo (AMD Chip)

Do not know the chip manufacturers are input: Egrep ' (VMX|SVM) '/proc/cpuinfo

If the flags: VMX or SVM indicate support for VT, if there is no output to indicate that your CPU is not supported, the KVM virtual machine will not be successfully installed.

2. Ensure that VT is turned on in the BIOS

Intel (R) Virtualization Tech [Enabled]

If necessary, open the vt-d in the BIOS

3. Make sure the kernel version is newer, support KVM

To view the kernel version with Uname-r, upgrade the kernel if the Linux version under 2.6.20.

Summarize:

In general, a virtual machine software, you can create a new virtual machine under Linux, compared with VMware, Linux KVM technology has a native kernel support, relatively faster than VMware. If you are using the desktop version of Ubuntu/centos, then it is recommended to install the virtual machine directly with KVM, there is no need to add another layer of VMware.

Reference:

Https://baike.baidu.com/item/KVM virtual Machines

What is a KVM virtual machine in Linux