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How can i access through ssh spring shell cli

I am trying to implement a simple cli application ( executable jar file running in linux docker image) using spring-shell library. After i started the Docker image with "docker run -it -p 8080:8080 springshelldemo" command my spring-shell app starts and the cli is available in cmd. How can i access this spring-shell cli from a second cmd using docker exec command (or some other better way) ?
I need this in order to make my app available to more than 1 users at the same time.

I found the answer to this problem. There is this great library on top of spring shell https://github.com/fonimus/ that gives you ssh functionality and with proper docker run file command you can access the spring shell through ssh with all features present.

Docker Springboot not running

I am new to docker,
I have pre cooked a docker image(updated and installed Java and other dependancies) and stored it on my GitHub repo,
I have stored a simple hello world Spring Boot application on an AWS S3 bucket,
I want to my DockerFile -
1. Get the docker image from my GitHub repo
2. Do an update patch
3. Set my working to directory to /home/ubuntu
4. Download application from S3 bucket using wget(it's publicly accessible)
5. run the application inside the container
After which I will run the image.
Command to build -
docker build -t someTag .
Command to run -
docker run -p 9090:8090 someTag
My java application jar that will be downloded is - docker.jar
And the application runs on port 8080
I have the following Dockerfile -
FROM someRepoHere
WORKDIR /home/ubuntu
RUN apt-get update
RUN cd /home/ubuntu
VOLUME /home/ubuntu
RUN wget S3BucketLocationHere
#RUN nohup java -jar docker.jar &
# Expose the default port
EXPOSE 8080
#Old command - CMD nohup java -jar docker.jar &
CMD ["java", "-jar", "docker.jar"]
The DockerFile is able to successfully build the image but,
My application is unreachable, It did not run inside the container.
Locally if I wget my application and run the nohup command, the application responds successfully.

Your command being run is what controls the existence of the container, when it exits/returns, the container exits and stops. Therefore you need to run your command in the foreground. When you are in an interactive shell in a container, that command is your shell. The command you've listed uses a shell, but that shell exits when it runs out of commands to process and nothing is running in the foreground:
CMD nohup java -jar docker.jar &
The string syntax will run the command with /bin/sh -c "nohup java ...".
A better option is to run with json syntax if you don't need a shell, and run your java app in the foreground, avoid the nohup and background syntax:
CMD ["java", "-jar", "docker.jar"]
A few more comments on the provided Dockerfile:
WORKDIR /home/ubuntu
RUN apt-get update
That only creates a cache inside your container that will become stale and result in cache misses if you try to use it in the future. This doesn't upgrade any packages if that's what you intended. That line should be removed.
RUN cd /home/ubuntu
This makes no filesystem changes, and will have no impact on the resulting image. The current shell state is lost after the RUN line exits, including the current directory and any variables you set. This line should be removed.
VOLUME /home/ubuntu
From this line forward, changes to /home/ubuntu will be lost. You'll only see anonymous volumes created as a result unless you specify a volume at runtime at the same location. You likely don't want the above volume line because it will break things like the next line.
RUN wget S3BucketLocationHere
This line has been obfuscated but I suspect you are outputting in /home/ubuntu because of the value of WORKDIR. Anything created here will be lost because of the VOLUME line above.

Cannot see Java Maven Tomcat-plugin web application in web browser

I want to build and run my Java Maven web app in a docker container. I tried with a following command:
docker run -it --name my_project -v "$PWD":/usr/src/my_project -w /usr/src/my_project maven:3.5.0-jdk-8 mvn clean install tomcat7:run
It correctly copies the resources, run maven clean install (successful build) and run with tomcat7-maven-plugin that is included in my pom.xml.
Everything works fine and logs are really similar to build and run locally on my windows machine:
Unfortunately on a web browser there is information "connection refused".
What could potentially cause the problem?:
- my application is windows specific and cannot run on linux?
- app is fully app and running but something wrong is with proxy configuration or port is not configured?
How can i proceed further - investigate the logs? Try to build on windows docker container?
P.S. I check IP of a container with Kitematic app for windows docker.

Possibly three issues. Once your used -w instead of -v
docker run -it --name my_project -v "$PWD":/usr/src/my_project -w /usr/src/my_project maven:3.5.0-jdk-8 mvn clean install tomcat7:run
Which I assumed was a Typo while posting. Next you didn't publish the port on your machine
docker run -p 9998:9998 -it --name my_project -v "$PWD":/usr/src/my_project -w /usr/src/my_project maven:3.5.0-jdk-8 mvn clean install tomcat7:run
This would map the port 9998 (right side) from your container to the port 9998 on your localhost.
Third and last one, your INFO log says listening on localhost:9998. This is not good. Because that means your war is listening from traffic generated inside the the container only and not from outside the container. You need to configure your war so it listens on all interfaces inside the container and bind should be 0.0.0.0:9998

How to keep springboot application alive after exiting putty

I am running my spring boot application on my server using putty via command
mvn spring-boot:run and it runs only when I have open ssh session. Is it possible to keep application alive after I disconnect session?
Or do I have to make executable war file and deploy to installed tomcat server on my ubunntu 14.04.
I know others ways to deploy boot apps but I want to know if it is possible in my approach.

You can run the command in the background and with nohup like so
nohup mvn spring-boot:run &
When you do this, the application runs in background even after you close ssh session.

In putty, you need to use nohup mvn spring-boot:run > spring-log.txt & to run the command in the background and this generates the spring-log.txt file.

If you don't want console logs to be written (you have logging frameworks which handles the application logs) then use this command
nohup mvn spring-boot:run </dev/null >/dev/null 2>&1 &
BTW, just curious, why are you using mvn spring-boot:run to run your program in your server? doesn't that require you to have maven runtime installed in your server as well?

If you are deploying your executable jar
nohup java -jar <your jar name>

Docker build hangs during downloads

Mac 10.10.5 here, using docker-machine to create a VirtualBox host VM for my local Docker. I have a project that builds an executable JVM located at build/libs/myapp-SNAPSHOT.jar. My Dockerfile, which is located in the root of the project, looks like:
FROM frolvlad/alpine-oraclejdk8:slim
VOLUME /tmp
ADD build/libs/myapp-SNAPSHOT.jar myapp.jar
RUN sh -c 'touch /myapp.jar'
ENTRYPOINT ["java","-jar","/myapp.jar"]
Please note, I don't wish to push my images to any registry, just keep/run them locally (for now). When I run:
docker build -t myorg/myapp .
I get the following console output:
myuser#mymachine:~/sandbox/myapp$docker build -t myorg/myapp .
Sending build context to Docker daemon 42.69 MB
Step 1 : FROM frolvlad/alpine-oraclejdk8:slim
slim: Pulling from frolvlad/alpine-oraclejdk8
d0ca440e8637: Downloading [=================================================> ] 2.295 MB/2.32 MB
0f86278f6be1: Downloading [=================================================> ] 3.149 MB/3.172 MB
c704a6161dca: Download complete
And then the command-line just hangs after printing that "Download complete" message. I've waited for as long as 30 minutes (!!!) and nothing happens.
Any ideas where I'm going awry?

The VM is probably hanging. Try the following: https://github.com/docker/machine/issues/1819#issuecomment-138981139
docker-machine rm -f default
rm -fv ~/.docker/machine
docker-machine -D create -d virtualbox default
There are more issues about this on OSX.
I think the best practice is to setup a Linux native build box if you are doing any serious development. That way you can run docker without any VM overhead(which is ironically one of the major pain points docker is trying to solve)
There's also a Docker Beta program which runs on libcontainer natively on OSX and Windows.