dockerでこのエラーでた ERROR: Couldn't connect to Docker daemon at http+docker://localhost - is it running? If it's at a non-standard location specify the URL with the DOCKER_HOST environment variable. docker

単純にdockerデーモンが起動してない状況でした

# /usr/local/bin/docker-compose build
ERROR: Couldn t connect to Docker daemon at http+docker://localhost - is it running?

If it s at a non-standard location specify the URL with the DOCKER_HOST environment variable.
#

# service docker start
Redirecting to /bin/systemctl start docker.service
#