Types of containers:
System containers (as run by LXD) are similar to virtual or physical machines.
- They run a full operating system inside them, you can run any type of workload, and you manage them exactly as you would a virtual or a physical machine.
- System containers could host several applications within a single system container.
- System containers run a full operating system giving them flexibility for the workload types they support.
Application containers (such as Docker), also known as process containers, as it runs a single process or a service per container.
- These containers are temporary, and you can create, delete and replace containers easily as needed.
- Application containers run a single app/process.
Both application and system containers share a kernel with the host operating system:
LXC vs LXD vs Docker
LXC is the technology allowing the segmentation of your system into independent containers.
LXD is a daemon running on top of LXC for running system containers. When it comes to storage, networking, and logging, LXD supports a variety of interfaces and features. Functionality-wise, LXD is similar to VMWare or KVM hypervisors, but is much lighter on resources and removes the usual virtualization overhead.
Docker is a containerization platform, specifically designed for microservice architecture, providing a way to decompose and isolate individual processes, which can then be scaled independently from the rest of the application or system they are a part of.
Running Docker in LXD
You can use LXD to create your virtual systems running inside the containers, segment them as you like, and easily use Docker to get the actual service running inside the container.
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