Create an image from a Dockerfile

Question

I am looking at a Docerfile like this:

FROM microsoft/aspnetcore:2.0 AS base

# Install the SSHD server
RUN apt-get update \
  && apt-get install -y --no-install-recommends openssh-server \
  && mkdir -p /run/sshd \
  && echo "root:Docker!" | chpasswd
#Copy settings file. See elsewhere to find them. 
COPY sshd_config /etc/ssh/sshd_config
COPY authorized_keys  root/.ssh/authorized_keys

# Install Visual Studio Remote Debugger
RUN apt-get install zip unzip
RUN curl -sSL https://aka.ms/getvsdbgsh | bash /dev/stdin -v latest -l ~/vsdbg

EXPOSE 2222

I am trying to create an image using this dockerfile. How can I do this? I have read many webpages over the last few hours eg this one https://odewahn.github.io/docker-jumpstart/building-images-with-dockerfiles.html , however they all seem to overcomplicate it as my research is telling me that there is only one command needed.

Answer 1

If Dockerfile is in your current directory, this command will build image and store it locally:

docker build -t "app:latest" .

Here is documentation for build command

Then you can run it in background with:

docker run -d -p 2222:2222 app

This command will create container and start it. Here is documentation for run command .

Answer 2

I'm not really sure what you consider 'overcomplicated' on that website?

There's one command on that site that says docker build -t "simple_flask:dockerfile" . . The only complication is that it adds a tag, which is explained directly underneath it

The only thing that might be simpler is not tagging it. so you do

docker build .

which means: build me an image. from the current directory.

Answer 3

Since you have a Docker file, you are required to do 4 additional steps:

1. docker build -t <app-name> . : Building your image

2. docker images : Check your image

3. docker run -d -p 2222:8080 myapp : Run your image

4. docker ps : Check running docker image

Refer Docker doc. for more detials