Day2

# To search for particular image
$ docker search <image name>
$ docker search centos

# To pull a particular image
$ docker image pull <image name>
$ docker image pull centos

# Run a container(Combination of image pull + run)
docker container run -d centos bash

# Show the history of an image
$ docker image history centos

# Dockerfile reference
https://docs.docker.com/engine/reference/builder/

# Dockerfile
FROM ubuntu
RUN apt-get update
RUN apt-get -y install nginx
CMD ["nginx","-g","daemon off;"]

# To build the image out from Dockerfile (without tag)
docker build .

# To build the image out from Dockerfile
docker build -t <tag name> .

# Dockefile copy
FROM busybox
COPY test.txt /tmp
CMD ["sh"]

# Dockerfile add
FROM busybox
ADD https://github.com/100daysofdevops/100daysofdevops/blob/master/README.md /tmp
CMD ["sh"]

# Dockerfile cmd
FROM busybox
CMD ["sh"]

# Dockerfile entrypoint
FROM busybox
ENTRYPOINT ["/bin/ping"]

# To check the image
docker image ls

# Display detailed information on one or more images
$ docker image inspect centos

# Dockerignore
$ cat .dockerignore 
*/*.txt

# Containers, Images, Local Volume and Cache Size
docker system df

# For verbose output
docker system df -v

# To test the layer 
FROM busybox
RUN dd if=/dev/zero of=/tmp/test1 bs=1M count=50
RUN dd if=/dev/zero of=/tmp/test2 bs=1M count=50
RUN rm -rf /tmp/test1
RUN rm -rf /tmp/test2

# To cleanup images
docker image prune

# To create a new image from a container change

docker container commit <container id> <image name>