Docker

Installation

https://docs.docker.com/engine/getstarted/step_one/

Examples

Run nginx container

docker run -d -p 80:80 --name webserver nginx

You should be able to access it by going to http://localhost
List all docker images

docker images

List running containers

docker ps

Copy file to a docker container

docker cp html.tar 213389b682d6:/tmp/

Connect to a running container

docker exec -it 213389b682d6 /bin/bash

Saving new container after the changes

docker commit -m "Adding ops runbook" -a "Igor" 213389b682d6 runbook

Run your new container

docker run -d -p 80:80 -it runbook /bin/bash

Login to the container shell

docker exec -it 7e7d9c35a216 bash

Exit from the container shell
Ctrl + p , Ctrl + q
Restart nginx inside your container

docker exec -it 213389b682d6 /etc/init.d/nginx restart

After docker service restart - make sure ecs-agent is running

root@ecs00-us-west-2b:~# docker start ecs-agent

Logging

It seems like docker puts logs in two places:

1.  Actual container logs

   /var/lib/docker/containers

2. docker system log

   /var/log/docker.log

The following options should take care of log rotation:
/etc/default/docker

DOCKER_OPTS="--pidfile=/var/run/docker.pid --log-level=warning --log-opt max-size=1g --storage-driver=zfs --storage-opt=zfs.fsname=zd0/containers"

log-level makes docker.log file less verbose.  log-opt makes container logs no bigger than 1GB