What is the architecture and components of Kubernetes? Kubernetes is deployment and management platforms. It offers container orchestration, a container runtime, container-centric infrastructure orchestration, load balancing, self-healing mechanisms. It is used to compose, scale, deploy, and manage application containers across host clusters. An environment running Kubernetes consists of the following basic components: a control plane (master), a distributed key-value storage system for keeping the cluster state consistent (etcd), and cluster nodes Kubernetes architecture components or K8s components include the Kubernetes control

What is the benefit of using CMD? CMD instruction can be used to set default command to execute when we run docker container. It allows the user to execute some particular command while running docker container. What is the benefit of using ENTRYPOINT? ENTRYPOINT instruction allows you to configure a container that will run as an executable. It has two forms – exec and shell Exec form allows to set commands and parameters and then use either form of CMD

Docker image is template used to build the docker containers Docker image contains application code, tools, dependencies and other files needed to make an application run Docker images are store in docker registry Docker images have multiple layers(base image, parent image, Layers), each one originates from the previous layer but is different from it The layered file systems are identified using UUID which are created using SHA256 algorithm. When we create a container – all layers are merged into 1

Docker update Update command is used to update the CPU and memory configuration of the container. Available options can be checked with docker update –help command docker wait docker wait command waits for one or more container to exit and provides the return status of the docker exit In the above example docker wait command gives the output when container 95d0f2b4f8cf was stopped

Advantages Return on Investment and Cost SavingsRapid DeploymentSecuritySimplicity and Faster ConfigurationsContinuous Integration Disadvantages Data in the containerThere are times when a container goes down, so after that, it needs a backup and recovery strategy Provide cross-platform compatibilityThe one major issue is if an application designed to run in a Docker container on Windows, then it can’t run on Linux or vice versa Run applications with graphical interfacesIn general, Docker is designed for hosting applications which run on the command line.

What is the diff between docker pause and docker unpause? The docker pause command suspends all processes in the specified containers. When suspending a process the SIGSTOP signal is used, which is observable by the process being suspended. With container pause we cannot execute any commands which will throw an error root@ip-172-31-7-71 centos]# docker exec b5358234e052 lsError response from daemon: Container b5358234e052 is paused, unpause the container before exec Docker unpause command is used to resume the suspended container to