Explanation
The Kubernetes object definition file is in YAML format789. Kubernetes objects are represented in the Kubernetes API, and you can express them in .yaml format7. You can execute kubectl get deployment
<deployment-name> -o yaml to get the deployment definition in a yaml format8.

Explanation
Virtual networks are logical networks that are decoupled from the underlying network hardware. This decoupling allows network administrators to manage their networks independently of the physical network topology. As such, virtual networks can span multiple devices, allowing for a high degree of flexibility and scalability. Furthermore, virtual networks are available on common Linux distributions, allowing for easy deployment and management.

Explanation
OS-level virtualization requires less duplication of hardware resources. This method allows multiple instances of an operating system or multiple different operating systems to run on a single physical server, sharing the same hardware resources. This results in more efficient use of hardware resources compared to other virtualization methods such as full virtualization or paravirtualization

Explanation
The SDN overlay model provisions tunnels between the virtual endpoints within and across data centers2. This model uses network overlays to support private communication between instances3. References from Juniper site: Microsoft Learn, Red Hat Customer Portal

Explanation
Docker containers are designed to be ephemeral, meaning they run based on their current configuration. When a Docker container is stopped, it does not automatically save changes made during its runtime. When you execute docker run, it starts a new instance of the container, not an existing version with its changes[14-16]. If you want to persist changes between runs, you need to commit changes to a new Docker image or use Docker volumes for data persistence[14-16]. References from Juniper site: Stack Overflow, Docker Docs