I need to start two services/commands in docker, from google I got that I can use ENTRYPOINT and CMD to pass different commands. but when I start the container only ENTRYPOINT script runs and CMD seems not running. since I am a new docker can you help me on how to run two commands.
Dockerfile :
FROM registry.suse.com/suse/sle15
ADD repolist/*.repo /etc/zypp/repos.d/
RUN zypper refs && zypper refresh
RUN zypper in -y bind
COPY docker-entrypoint.d/* /docker-entrypoint.d/
COPY --chown=named:named named /var/lib/named
COPY --chown=named:named named.conf /etc/named.conf
COPY --chown=named:named forwarders.conf /etc/named.d/forwarders.conf
ENTRYPOINT [ "./docker-entrypoint.d/startbind.sh" ]
CMD ["/usr/sbin/named","-g","-t","/var/lib/named","-u","named"]
startbind.sh:
#! /bin/bash
/usr/sbin/named.init start
Thanks & Regards,
Mohamed Naveen
You can use supervisor tools for managing multiple services inside a single docker container.
Check out the below example(running Redis and Django server using single CMD):
Dockerfile:
# Base Image
FROM alpine
# Installing required tools
RUN apk --update add nano supervisor python3 redis
# Adding Django Source code to container
ADD /django_app /src/django_app
# Adding supervisor configuration file to container
ADD /supervisor /src/supervisor
# Installing required python modules for app
RUN pip3 install -r /src/django_app/requirements.txt
# Exposing container port for binding with host
EXPOSE 8000
# Using Django app directory as home
WORKDIR /src/django_app
# Initializing Redis server and Gunicorn server from supervisors
CMD ["supervisord","-c","/src/supervisor/service_script.conf"]
service_script.conf file
## service_script.conf
[supervisord] ## This is the main process for the Supervisor
nodaemon=true ## This setting is to specify that we are not running in daemon mode
[program:redis_script] ## This is the part where we give the name and add config for our 1st service
command=redis-server ## This is the main command to run our 1st service
autorestart=true ## This setting specifies that the supervisor will restart the service in case of failure
stderr_logfile=/dev/stdout ## This setting specifies that the supervisor will log the errors in the standard output
stderr_logfile_maxbytes = 0
stdout_logfile=/dev/stdout ## This setting specifies that the supervisor will log the output in the standard output
stdout_logfile_maxbytes = 0
## same setting for 2nd service
[program:django_service]
command=gunicorn --bind 0.0.0.0:8000 django_app.wsgi
autostart=true
autorestart=true
stderr_logfile=/dev/stdout
stderr_logfile_maxbytes = 0
stdout_logfile=/dev/stdout
stdout_logfile_maxbytes = 0
Final output:
Redis and Gunicorn service in same docker container
You can read my complete article on this, the link is given below:
Link for complete article
Options to run more than one service within the container described really well in this official docker article:
multi-service_container.
I'd recommend reviewing why you need two services in one container(shared data volume, init, etc) cause by properly separating the services you'll have ready to scale architecture, more useful logs, easier lifecycle/resource management, and easier testing.
Within startbind.sh
you can do:
#! /bin/bash
#start second servvice here, and push it to background:
/usr/sbin/secondesrvice.init start &
#then run the last commands:
/usr/sbin/named.init start
your /usr/sbin/named.init start (the last command on the entry point) command must NOT go into background, you need to keep it on the foreground.
If this last command is not kept in foreground, Docker will exit.
You can add to startbind.sh the two service start. You can use RUN command also. RUN execute commands in docker container. If dont work, you can ask me to keep helping you.
Related
I have a project which I had previously successfully deployed to Google Cloud Run, and set up with a trigger such that upon pushing to the repo's main branch on Github, it would automatically deploy. It worked great.
Then I tried to rename the github repo, which meant deleting and creating a new trigger, and now I cannot get it working again.
Everytime, the build succeeds but deployment fails with this error in Cloud Build:
Step #2 - "Deploy": ERROR: (gcloud.run.services.update) Cloud Run error: Container failed to start. Failed to start and then listen on the port defined by the PORT environment variable. Logs for this revision might contain more information.
I have not changed anything other than the repo name, leading me to believe the fix is not with my code, but I tried some changes there anyway.
I have looked into the solutions set forth in this post. However, I believe I am listening on the correct port.
My app is using Python and Flask, and contains this:
if __name__ == "__main__":
app.run(debug=False, host="0.0.0.0", port=int(os.environ.get("PORT", 8080)))
Which should use the ENV var Port (8080) and otherwise default to 8080. I also tried just using port=8080.
I tried explicitly exposing the port in the Dockerfile, which also did not work:
FROM python:3.7
#Copy files into docker image dir, and make that the current working dir
COPY . /docker-image
WORKDIR /docker-image
RUN pip install -r requirements.txt
CMD ["flask", "run", "--host", "0.0.0.0"]
EXPOSE 8080
Cloud Run does seem to be using port 8080 - if I dig into the response, I see this nested under Response.spec.container.0 :
ports: [
0: {
containerPort: 8080
name: "http1"
}
]
All that said, if I look at the logs, it shows "Now running on Port 5000".
I have no idea where that Port 5000 is coming from or being set, but trying to change the ports in Python/Flask and the Dockerfile to 5000 leads to the same errors.
How do I get it to run on Port 8080? It's very strange to me that this was working FINE prior to renaming the repo and creating a new trigger. How is this setup different? The Trigger does not give an option to set the port so I'm not sure how that caused this error.
You have mixed things. Flask command default port is effectively 5000. If you want to change it, you need to change your flask run command with the --port= parameter
CMD ["flask", "run", "--host", "0.0.0.0","--port","8080"]
In addition, your flask run command, is a flask runtime and totally ignore the standard python entrypoint if __name__ == "__main__":. If you want to use this entrypoint, use the Python runtime
CMD ["python", "<main file>.py"]
I am trying to deploy a Python App using Docker on Google Cloud
After typing the command gcloud run deploy --image gcr.io/id/name, I get this error:
ERROR: (gcloud.run.deploy) Cloud Run error: Container failed to start. Failed to start and then listen on the port defined by the PORT environment variable. Logs for this revision might contain more information.
Logs explorer:
TEST_MODE = input()
EOFError: EOF when reading a line
I know with error is caused by trying to take in user input, and with Dockers this command solves the error:
docker run -t -i
Any idea how to run this with gcloud?
Your example does not run a server and so it's not accepted by Cloud Run.
Cloud Run expects a server to be running on PORT (generally this evaluates to 8080 but you should not assume this).
While it's reasonable to want to run arbitrary containers on Cloud Run, the service expects to something to respond via HTTP.
One option would be to simply jam an HTTP server into your container that listens on PORT and then run your Python app alongside it but, Python is single-threaded and so it's less easy to do this. Plus, it's considered an anti-pattern to run multiple processes in a single container.
Therefore I propose the following:
Rewrite your app to return the input as an HTTP GET:
main.py:
from flask import Flask
app = Flask(__name__)
#app.route('/hello/<name>')
def hello(name):
return "Hello {name}".format(name=name)
if __name__ == '__main__':
app.run(host='127.0.0.1', port=8080, debug=True)
Test it:
python3 main.py
* Running on http://127.0.0.1:8080/ (Press CTRL+C to quit)
NOTE Flask is running on localhost (127.0.0.1). We need to change this when we run it in a container. It's running on 8080
NAME="Freddie"
curl http://localhost:8080/hello/${NAME}
Hello Freddie
Or browse: http://localhost:8080/hello/Freddie
Containerize this:
Dockerfile:
FROM python:3.10-rc-slim
WORKDIR /app
RUN pip install flask gunicorn
COPY main.py .
ENV PORT 8080
CMD exec gunicorn --bind 0.0.0.0:$PORT main:app
NOTE ENV PORT 8080 sets the environment variable PORT to a value of 8080 unless we specify otherwise (we'll do that next)
NOTE The image uses gunicorn as a runtime host for Flask. This time the Flask service is bound to 0.0.0.0 which permits it to accessible from outside the container (which we need) and it uses the value of PORT
Then:
# Build
docker build --tag=66458821 --file=./Dockerfile .
# Run
PORT="9999"
docker run \
--rm --interactive --tty \
--env=PORT=${PORT} \
--publish=8080:${PORT} \
66458821
[INFO] Starting gunicorn 20.0.4
[INFO] Listening at: http://0.0.0.0:9999 (1)
NOTE Because --env=${PORT}, Flask now runs on 0.0.0.0:9999 but, we remap this port to 8080 on the host. This is just to show how the PORT variable is now used by the container
Test it (using the commands as before)!
Publish it and gcloud run deploy ...
Test it!
I am trying to spin up a webapp using docker build. For generating certs, I want to use certbot. However, if I just put
RUN certbot --nginx,
I get
Enter email address (used for urgent renewal and security notices) (Enter 'c' to
cancel): Plugins selected: Authenticator nginx, Installer nginx
An unexpected error occurred:
EOFError.
Is there a way to provide this information in the Dockerfile or ignore it ?
RUN certbot -n -m ${EMAIL} -d ${DOMAINS} --nginx
My one suggestion is not to do this during docker build, but instead generate the cert when the container starts up. This is because letsencrypt will attempt to connect to your server at the domains you're specifying, which probably is not where you're building the image.
To decrease startup time though, you'll want to skip bootstrapping dependencies (but you will need these installed). For this purpose, I would use the following command in your Dockerfile to list certificates (this will ensure dependencies are properly installed) and then alter the CMD (assuming you're using the nginx image)
Dockerfile:
ARG EMAIL_ARG=defaultemail#example.com
ARG DOMAINS_ARG=example.com
ENV EMAIL=${EMAIL_ARG}
ENV DOMAINS=${DOMAINS_ARG}
RUN certbot --help
...
CMD ["sh", "-c", "certbot --no-bootstrap -n -m ${EMAIL} -d ${DOMAINS} --nginx", "&&", "nginx", "-g", "daemon off;"]
The -n is for non-interactive mode
The --no-bootstrap is to skip the bootstrapping of dependencies (installing python and such)
The -m is to specify the email used for important notifications
The -d is to specify a comma separated list of domains
Using "sh", "-c" will invoke a shell when the command is executed, so you'll get the shell like behavior of replacing your environment variables with their values. Passing the values in to the build as build args doesn't expose them at startup time of your container, which is why they are then being placed into environment variables. The added benefit of them being used from environment variables is you can override these values in different environments (dev, test, stage, prod, etc...).
I've been working in a sample ruby-on-rails application and deploying docker image in a linux server (ubuntu 14.04).
Here is my Dockerfile:
FROM ruby:2.1.5
RUN apt-get update -qq && apt-get install -y build-essential libpq-dev nodejs
RUN mkdir /rails_docker_demo
WORKDIR /rails_docker_demo
ADD Gemfile /rails_docker_demo/Gemfile
ADD Gemfile.lock /rails_docker_demo/Gemfile.lock
RUN bundle install
ADD . /rails_docker_demo
# CMD bundle exec rails s -p 3000 -b 0.0.0.0
# EXPOSE 3000
docker-compose.yml:
version: '2'
services:
db:
image: postgres
web:
build: .
command: bundle exec rails s -p 3000 -b '0.0.0.0'
image: atulkhanduri/rails_docker_demos
volumes:
- .:/rails_docker_demo
ports:
- "3000:3000"
depends_on:
- db
deploy.sh:
#!/bin/bash
docker build -t atulkhanduri/rails_docker_demo .
docker push atulkhanduri/rails_docker_demo
ssh username#ip-address << EOF
docker pull atulkhanduri/rails_docker_demo:latest
docker stop web || true
docker rm web || true
docker rmi atulkhanduri/rails_docker_demo:current || true
docker tag atulkhanduri/rails_docker_demo:latest atulkhanduri/rails_docker_demo:current
docker run -d --restart always --name web -p 3000:3000 atulkhanduri/rails_docker_demo:current
EOF
Now my problem is that I'm not able to use docker-compose commands like docker-compose up, to run the application server.
When I uncomment the last two lines fromDockerfile i.e,
CMD bundle exec rails s -p 3000 -b 0.0.0.0
EXPOSE 3000
then I'm able to run the server on port 3000 but getting error could not translate host name "db" to address: Name or service not known. (my database.yml has "db" as host.) This is because postgres image is not used as I'm not using docker-compose file is not.
EDIT:
Output of docker network ls:
NETWORK ID NAME DRIVER SCOPE
b466c9f566a4 bridge bridge local
7cce2e53ee5b host host local
bfa28a6fe173 none null local
P.S: I've searched a lot in the internet but not yet able to use the docker-compose file.
Assumptions
If I am reading what you've done here correctly, my answer assumes the following two things.
You are using docker-compose to run the database container.
You are using plain docker commands (not docker-compose) to start the application server ("web").
First, I would suggest not doing that, it is a lot simpler to use docker-compose for both. However, I'll answer based on the above, assuming that there is some valid reason you cannot use docker-compose to run the "web" container.
About container and network names
When you run the docker-compose command to start the db container, among other things, two things happen.
The container is given a new name, composed of the directory you run the compose setup from, the static name in compose (db), and a number. So let's say you have this all in a directory name myapp, you would have a new container named myapp_db_1. You can see what it is named using docker ps.
A network bridge is created if it didn't already exist, named something like myapp_default - again, named after the directory that the compose setup is inside of.
Connecting to the right network
The problem is that your non-compose container is attached to the default network (probably docker_default), but your db container is attached to myapp_default. The two networks do not know about each other. You need to connect them. It probably makes more sense to tell the web app container to attach to the compose network.
First, get the correct network name. You can see all networks using docker network ls. It might look like this:
$ docker network ls
NETWORK ID NAME DRIVER SCOPE
c1f5764a112b bridge bridge local
175efb89adef docker_default bridge local
5185ff0e1054 myapp_default bridge local
Once you have the correct name, update your run command to know about the network using the --network option.
docker run -d --restart always --name web \
-p 3000:3000 --network myapp_default \
atulkhanduri/rails_docker_demo:current
Once it is attached to the proper network, the name "db" should resolve correctly.
If you used docker-compose to start both of them, this would not be necessary (this is one of the things docker-compose just takes care of for you silently).
Getting this to run on your server
In the comments, you mention that you are having some issues with compose on the server. Specifically you said:
Do I need to copy my complete project on the server? Can't I run the application from docker image only? Actually, I've copied docker-compose in server and it throws errors for Gemfile, then I copied Gemfile, then it says it should be a rails app. So I guess I need to copy my complete folder in server. Can you please confirm?
Let's look at some parts of your Dockerfile. I'll add some comments inline.
## Make a new directory, and then make it the current directory
RUN mkdir /rails_docker_demo
WORKDIR /rails_docker_demo
## Copy Gemfile and Gemfile.lock into this directory from outside
ADD Gemfile /rails_docker_demo/Gemfile
ADD Gemfile.lock /rails_docker_demo/Gemfile.lock
## Run the bundle installer, which will install to this directory
RUN bundle install
## Finally, copy everything from the outside local dir to here
ADD . /rails_docker_demo
So, clearly, /rails_docker_demo is your application directory within the container. You've installed a bunch of stuff here, and this will become a part of your image. When you push your image to the registry, then pull it down on the server (as you do in the deploy script), this will all come with it.
Now let's look at (some of) docker-compose.yml.
services:
web:
volumes:
- .:/rails_docker_demo
Here you have defined a volume mount, mounting the current directory (wherever docker-compose.yml lives) as /rails_docker_demo. When you do that, whatever happens to exist on the server is now available in /rails_docker_demo, but this mount undoes all the work from Dockerfile that I just mentioned above. Instead of having the resources you installed when you built the image, you have only whatever is on the server in the . directory. The mount is on top of the image's existing /rails_docker_demo directory, hiding its contents and replacing them with whatever is on the server at the moment.
Unless there is a reason you put this mount here, you probably just need to remove that volume mount from docker-compose.yml. You will still need docker-compose.yml on the server, but you should not need the rest of it (aside from the image, of course).
This mount you have done is a useful thing - for development purposes. It would let you use the container to run the application and quickly have code changes show up (without rebuilding the image). But in the case of your deployment, it is just causing trouble.
Try moving the EXPOSE above CMD, .e.g.
FROM ruby:2.1.5
RUN apt-get update -qq && apt-get install -y build-essential libpq-dev nodejs
RUN mkdir /rails_docker_demo
WORKDIR /rails_docker_demo
ADD Gemfile /rails_docker_demo/Gemfile
ADD Gemfile.lock /rails_docker_demo/Gemfile.lock
RUN bundle install
ADD . /rails_docker_demo
EXPOSE 3000
CMD bundle exec rails s -p 3000 -b 0.0.0.0
I want to install linode/lamp container to work on some wordpress project locally without messing up my machine with all the lamp dependencies.
I followed this tutorial which worked great (it's actually super simple).
Now I'd like to use docker-compose because I find it more convenient to simply having to type docker-compose up and being good to go.
Here what I have done:
Dockerfile:
FROM linode/lamp
RUN service apache2 start
RUN service mysql start
docker-compose.yml:
web:
build: .
ports:
- "80:80"
volumes:
- .:/var/www/example.com/public_html/
When I do docker-compose up, I get:
▶ docker-compose up
Recreating gitewordpress_web_1...
Attaching to gitewordpress_web_1
gitewordpress_web_1 exited with code 0
Gracefully stopping... (press Ctrl+C again to force)
I'm guessing I need a command argument in my docker-compose.yml but I have no idea what I should set.
Any idea what I am doing wrong?
You cannot start those two processes in the Dockerfile.
The Dockerfile determines what commands are to be run when building the image.
In fact many base images like the Debian ones are specifically designed to not allow starting any services during build.
What you can do is create a file called run.sh in the same folder that contains your Dockerfile.
Put this inside:
#!/usr/bin/env bash
service apache2 start
service mysql start
tail -f /dev/null
This script just starts both services and forces the console to stay open.
You need to put it inside of your container though, this you do via two lines in the Dockerfile. Overall I'd use this Dockerfile then:
FROM linode/lamp
COPY run.sh /run.sh
RUN chmod +x /run.sh
CMD ["/bin/bash", "-lc", "/run.sh"]
This ensures that the file is properly ran when firing up the container so that it stays running and also that those services actually get started.
What you should also look out for is that your port 80 is actually available on your host machine. If you have anything bound to it already this composer file will not work.
Should this be the case for you ( or you're not sure ) try changing the port line to like 81:80 or so and try again.
I would like to point you to another resource where LAMP server is already configured for you and you might find it handy for your local development environment.
You can find it mentioned below:
https://github.com/sprintcube/docker-compose-lamp