Introduction
Linux system offers different technologies to create virtual environments that can be used to run multiple applications or even separate operating systems. Two popular technologies that are used for virtualization are LXC containers and KVM virtualization. In this article, we will discuss the differences between LXC containers and KVM virtualization and when to use which technology.
LXC Containers
LXC containers are a type of OS-level virtualization that allows you to run multiple isolated Linux systems on a single host system. Each LXC container has its own file system, networking, and processes, which can be controlled and managed independently. LXC containers are lightweight and provide fast performance since they directly run on the host kernel without any overhead of a separate hypervisor. They can be useful for running multiple services on a single host or testing different configurations.
When you use LXC containers, you share the host system's kernel with the containers. This means that all the containers use the same kernel, and any changes to the kernel affect all the containers. Therefore, it is essential to keep the host system's kernel up-to-date and secure. Another limitation is that you can only run Linux-based operating systems inside LXC containers.
KVM Virtualization
KVM (Kernel-based Virtual Machine) virtualization allows you to run complete operating systems, including Windows and other non-Linux based systems, on a single host computer. KVM virtualization creates a fully isolated environment for each guest operating system, including its own kernel and processes. This makes it useful for hosting multiple different operating systems or running legacy applications that require an older version of an operating system.
KVM virtualization requires a hypervisor, which adds some overhead compared to LXC containers. However, it provides more flexibility and control over each guest system's hardware resources, such as CPU, RAM, and storage. Each guest can be given a specific amount of resources based on its requirements, which ensures that the guest system has the resources it needs to run smoothly.
When to Use LXC Containers
LXC containers are a good choice when you want to run multiple isolated Linux systems on a single host. They can provide fast performance and lower resource overhead compared to KVM virtualization. LXC containers are useful for running multiple services or applications on a single host, such as running different databases, web servers, or application servers. They can also be useful for testing different configurations since you can quickly spin up and tear down containers.
When to Use KVM Virtualization
If you need to run non-Linux-based operating systems or require full isolation between guest systems, KVM virtualization is a good choice. KVM virtualization provides a complete isolated environment for each guest system, which can be useful for hosting multiple different operating systems or running legacy applications that require a specific version of an operating system.
KVM virtualization provides more control over each guest system's hardware resources, which can ensure that each guest has the resources it needs to run smoothly. Therefore, KVM virtualization is a good choice when stability and performance are essential.
Conclusion
Choosing between LXC containers and KVM virtualization depends on your requirements and the types of workloads you need to run. LXC containers are good for running multiple isolated Linux systems on a single host, while KVM virtualization provides complete isolation between guest systems and supports non-Linux-based operating systems. Both technologies have their benefits and drawbacks, and the choice depends on your specific needs.
