Editing User-mode Linux (section)

{{Short description|Virtualisation software}}
{{update|date=May 2019}}
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| title                  = User-mode Linux
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| genre                  = [[Virtualization]]
| license                = [[GNU General Public License]]
| website                = {{URL|http://user-mode-linux.sourceforge.net/}}
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'''User-mode Linux''' ('''UML''') is a [[virtualization]] system for the [[Linux]] operating system based on an architectural [[porting|port]] of the [[Linux kernel]] to its own [[system call]] interface, which enables multiple virtual Linux kernel-based operating systems (known as guests) to run as an application within a normal Linux system (known as the host). A Linux kernel compiled for the ''um'' architecture can then boot as a process under another Linux kernel, entirely in [[User space and kernel space|user space]], without affecting the host environment's configuration or stability.

This method gives the user a way to run many virtual Linux machines on a single piece of hardware, allowing some isolation, typically without changing the configuration or stability of the host environment because each guest is just a regular application running as a process in user space.