How to check if the docker engine and a docker container are running?

If you are looking for a specific container, you can run:

if [ "$( docker container inspect -f '{{.State.Running}}' $container_name )" == "true" ]; then ...

To avoid issues with a container that is in a crash loop and constantly restarting from showing that it's up, the above can be improved by checking the Status field:

if [ "$( docker container inspect -f '{{.State.Status}}' $container_name )" == "running" ]; then ...

If you want to know if dockerd is running itself on the local machine and you have systemd installed, you can run:

systemctl show --property ActiveState docker

You can also connect to docker with docker info or docker version and they will error out if the daemon is unavailable.

I ended up using

docker info

to check with a bash script if docker engine is running.

EDIT: which can be used to fail your script if docker isn't running, like so:

#!/usr/bin/env bashif ! docker info > /dev/null 2>&1; then  echo "This script uses docker, and it isn't running - please start docker and try again!"  exit 1fi

you can check docker state using: systemctl is-active docker

➜  ~  systemctl is-active dockeractive

you can use it as:

➜  ~  if [ "$(systemctl is-active docker)" = "active" ]; then echo "is alive :)" ; fiis alive :)➜  ~  sudo systemctl stop docker➜  ~  if [ "$(systemctl is-active docker)" = "active" ]; then echo "is alive :)" ; fi * empty response *