Fedora 38
Sponsored Link

Podman : Use Dockerfile2023/04/26

 
Use Dockerfile and create Container images automatically.
It is also useful for configuration management for Container images.
[1] For example, Create a Dockerfile that Nginx is installed and started.
[root@dlp ~]#
vi Dockerfile
# create new

FROM fedora
MAINTAINER ServerWorld <admin@srv.world>

RUN dnf -y install nginx
RUN echo "Dockerfile Test on Nginx" > /usr/share/nginx/html/index.html

EXPOSE 80
CMD ["/usr/sbin/nginx", "-g", "daemon off;"]

# build image ⇒ docker build -t [image name]:[tag] .

[root@dlp ~]#
podman build -t srv.world/fedora-nginx:latest .

STEP 1/6: FROM fedora
STEP 2/6: MAINTAINER ServerWorld <admin@srv.world>
--> c58442ef01dd
STEP 3/6: RUN dnf -y install nginx
.....
.....
Successfully tagged srv.world/fedora-nginx:latest
97533117cdc8b313bf8111deff1ca483fdc82632e5451abe12160749c9b443c1

[root@dlp ~]#
podman images

REPOSITORY                         TAG         IMAGE ID      CREATED         SIZE
srv.world/fedora-nginx             latest      97533117cdc8  18 seconds ago  420 MB
srv.world/fedora-httpd             latest      51d32e13e2f4  6 minutes ago   477 MB
registry.fedoraproject.org/fedora  latest      c9bfca6d0ac2  6 days ago      196 MB

# run container

[root@dlp ~]#
podman run -d -p 80:80 srv.world/fedora-nginx

bd054731f6829a78c9df98645881358b774e3ac55a3e99cce64ce76daab65ff5

[root@dlp ~]#
podman ps

CONTAINER ID  IMAGE                          COMMAND               CREATED         STATUS         PORTS               NAMES
bd054731f682  srv.world/fedora-nginx:latest  /usr/sbin/nginx -...  10 seconds ago  Up 10 seconds  0.0.0.0:80->80/tcp  keen_jemison

# verify accesses

[root@dlp ~]#
curl localhost

Dockerfile Test on Nginx
# also possible to access via container network

[root@dlp ~]#
podman inspect -l | grep \"IPAddress

               "IPAddress": "10.88.0.10",
                         "IPAddress": "10.88.0.10",

[root@dlp ~]#
curl 10.88.0.10

Dockerfile Test on Nginx
The format of Dockerfile is [INSTRUCTION arguments] .
Refer to the following description for INSTRUCTION.
INSTRUCTION Description
FROM It sets the Base Image for subsequent instructions.
MAINTAINER It sets the Author field of the generated images.
RUN It will execute any commands when Docker image will be created.
CMD It will execute any commands when Docker container will be executed.
ENTRYPOINT It will execute any commands when Docker container will be executed.
LABEL It adds metadata to an image.
EXPOSE It informs Docker that the container will listen on the specified network ports at runtime.
ENV It sets the environment variable.
ADD It copies new files, directories or remote file URLs.
COPY It copies new files or directories.
The differences of [ADD] are that it's impossible to specify remote URL and also it will not extract archive files automatically.
VOLUME It creates a mount point with the specified name and marks it as holding externally mounted volumes from native host or other containers
USER It sets the user name or UID.
WORKDIR It sets the working directory.

Matched Content