Docker images are basically a collection of filesystems One copy of an image of gets mounted to each container Images can be stored in a repository for use by other orgs Docker images can contain one or more filesystems Each filesystem in a docker image is called a layer The base layer is always the root filesystem When multiple layers exist in a docker image, the top layer will get priority When we create a container, all layers get merged

Docker Update The docker update command dynamically updates container configuration. We can use this command to prevent containers from consuming too many resources from their Docker host. With this command, we can place limits on a single container or on many. Before update cpu shares option – After update cpu shares option – Docker Wait Block until one or more containers stop, then print their exit codes Example of running docker wait – Start a container in the background. Run

What is the difference between docker pause and docker unpause? The command “docker pause” suspends all processes in the specified containers. Usually the SIGSTOP signal is sent to the process, which is observable by the process being suspended. However, the command “docker unpause” automatically un-suspends the processes in the specified containers. Usually this is accomplished via the SIGCONT signal. What is the difference between docker stop and docker kill? The command “docker stop” sends a SIGTERM signal to the main