Docker is awesome #
There is something in containerization and virtualization that attracts me very much. I think it’s the ultimate separation of concerns, the break down of complexity and declouping of system components.
Running a container exposing a port: #
Exposes the container 80 port as a local/host 8080:
docker run -p 8080:80 edpichler/nginx
Entering inside a running docker container #
docker exec -it e4383e55958d /bin/bash
Listeing all containers: #
docker ps -a
Deleting forcevily all the containers: #
docker rm -f $(docker ps -a -q)
Deleting all images that are not being used by running containers #
The additional filter is to do not delete images downloaded less than 2 days ago.
docker system prune -a --filter "until=$((2*24))h"
If you want to add on crontab, the -f flag will just prevent of the confirmation prompt be showed during the cron job running:
docker system prune -af --filter "until=$((2*24))h"
Docker Swarm #
Make a node inactive/active #
It will stops imediatelly all running containers in that node. They will be balanced to other nodes, though (if its configuration allows it).
docker node ls docker node update --availability drain 15wkcqw42fjzb1aqoavyfkk13 docker node update --availability active 15wkcqw42fjzb1aqoavyfkk13