Which term describes a virtualization approach where containers share the host OS kernel but remain isolated?

Which term describes a virtualization approach where containers share the host OS kernel but remain isolated?

• A. Container-Based Virtualization
• B. Emulation
• C. Type I (Bare Metal)
• D. Metadata

Answer: (A)

Containers use a shared host OS kernel while keeping each application in its own isolated user space. This isolation is built with kernel features like namespaces, which separate processes, networks, and file systems, and control groups (cgroups), which limit resource usage. Because the container packages the application and its dependencies but doesn't run a separate OS, it’s lightweight and starts quickly while still keeping things isolated from other containers and the host. This is why this approach is described as container-based virtualization. Emulation would involve running code intended for one architecture on another, or otherwise simulating hardware, which isn’t about sharing a kernel. Bare-metal Type I virtualization runs full virtual machines with their own kernels on hardware managed by a hypervisor, not sharing the host kernel. Metadata is simply data about data, not a virtualization method.

Containers use a shared host OS kernel while keeping each application in its own isolated user space. This isolation is built with kernel features like namespaces, which separate processes, networks, and file systems, and control groups (cgroups), which limit resource usage. Because the container packages the application and its dependencies but doesn't run a separate OS, it’s lightweight and starts quickly while still keeping things isolated from other containers and the host. This is why this approach is described as container-based virtualization.

Emulation would involve running code intended for one architecture on another, or otherwise simulating hardware, which isn’t about sharing a kernel. Bare-metal Type I virtualization runs full virtual machines with their own kernels on hardware managed by a hypervisor, not sharing the host kernel. Metadata is simply data about data, not a virtualization method.