based on Moving docker-compose containersets
I have loaded the images :
$ docker images -a
REPOSITORY TAG IMAGE ID CREATED SIZE
br/irc latest 3203cf074c6b 23 hours ago 377MB
openjdk 8u131-jdk-alpine a2a00e606b82 5 days ago 101MB
nginx 1.13.3-alpine ba60b24dbad5 4 months ago 15.5MB
but now i want to run them, as they would run with docker-compose, but i cannot find any example.
here is the docker-compose.yml
version: '3'
services:
irc:
build: irc
hostname: irc
image: br/irc:latest
command: |
-Djava.net.preferIPv4Stack=true
-Djava.net.preferIPv4Addresses
run-app
volumes:
- ./br/assets/br.properties:/opt/br/src/java/br.properties
nginx:
hostname: nginx
image: nginx:1.13.3-alpine
ports:
- "80:80"
links:
- irc:irc
volumes:
- ./nginx/assets/default.conf:/etc/nginx/conf.d/default.conf
so how can i run the container, and attach to it, to see if its running, and in what order do i run these three images. Just started with docker, so not sure of the typical workflow ( build, run, attach etc )
so even though i do have docker-compose yml file, but since i have the build images from another host, can i possibly run docker commands to run and execute the images ? making sure that the local images are being referenced, and not the ones from docker registry.
Thanks #tgogos, this does give me a general overview, but specifically i was looking for:
$ docker run -dit openjdk:8u131-jdk-alpine
then:
$ docker ps -a
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
cc6ceb8a82f8 openjdk:8u131-jdk-alpine "/bin/sh" 52 seconds ago Up 51 seconds vibrant_hodgkin
shows its running
2nd:
$ docker run -dit nginx:1.13.3-alpine
3437cf295f1c7f1c27bc27e46fd46f5649eda460fc839d2d6a2a1367f190cedc
$ docker ps -a
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
3437cf295f1c nginx:1.13.3-alpine "nginx -g 'daemon ..." 20 seconds ago Up 19 seconds 80/tcp vigilant_kare
cc6ceb8a82f8 openjdk:8u131-jdk-alpine "/bin/sh" 2 minutes ago Up 2 minutes vibrant_hodgkin
then: finally:
[ec2-user#ip-10-193-206-13 DOCKERLOCAL]$ docker run -dit br/irc
9f72d331beb8dc8ccccee3ff56156202eb548d0fb70c5b5b28629ccee6332bb0
$ docker ps -a
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
9f72d331beb8 br/irc "/opt/irc/grailsw" 8 seconds ago Up 7 seconds 8080/tcp cocky_fermi
3437cf295f1c nginx:1.13.3-alpine "nginx -g 'daemon ..." 56 seconds ago Up 55 seconds 80/tcp vigilant_kare
cc6ceb8a82f8 openjdk:8u131-jdk-alpine "/bin/sh" 2 minutes ago Up 2 minutes vibrant_hodgkin
All three UP !!!!
Your question is about docker-compose but you also ask things about run, build, attach which makes me think I should try to help you with some basic information (which wasn't so easy for me to cope with a couple of months ago :-)
images
Images are somehow the base from which containers are created. Docker pulls images from http://hub.docker.com and stores them in your host to be used every time you create a new container. Changes in the container do not affect the base image.
To pull images from docker hub, use docker pull .... To build your own images start reading about Dockerfiles. A simple Dockerfile (in an abstract way) would look like this:
FROM ubuntu # base image
ADD my_super_web_app_files # adds files for your app
CMD run_my_app.sh # starts serving requests
To create the above image to your host, you use docker build ... and this is a very good way to build your images, because you know the steps taken to be created.
If this procedure takes long, you might consider later to store the image in a docker registry like http://hub.docker.com, so that you can pull it from any other machine easily. I had to do this, when dealing with ffmpeg on a Raspberry Pi (the compilation took hours, I needed to pull the already created image, not build it from scratch again in every Raspberry).
containers
Containers are based on images, you can have many different containers from the same image on the same host. docker run [image] creates a new container based on that image and starts it. Many people here start thinking containers are like mini-VMs. They are not!
Consider a container as a process. Every container has a CMD and when started, executes it. If this command finishes, or fails, the container stops, exits. A good example for this is nginx: go check the official Dockerfile, the command is:
CMD ["nginx"]
If you want to see the logs from the CMD, you can docker attach ... to your container. You can also docker stop ... a running container or docker start ... an already stopped one. You can "get inside" to type commands by:
docker exec -it [container_name] /bin/bash
This opens a new tty for you to type commands, while the CMD continues to run.
To read more about the above topics (I've only scratched the surface) I suggest you also read:
Is it possible to start a shell session in a running container (without ssh)
Docker - Enter Running Container with new TTY
How do you attach and detach from Docker's process?
Why docker container exits immediately
~jpetazzo: If you run SSHD in your Docker containers, you're doing it wrong!
docker-compose
After you feel comfortable with these, docker-compose will be your handy tool which will help you manipulate many containers with single line commands. For example:
docker compose up
Builds, (re)creates, starts, and attaches to containers for a service.
Unless they are already running, this command also starts any linked services.
The docker-compose up command aggregates the output of each container (essentially running docker-compose logs -f). When the command exits, all containers are stopped. Running docker-compose up -d starts the containers in the background and leaves them running
To run your docker-compose file you would have to execute:
docker-compose up -d
Then to see if your containers are running you would have to run:
docker ps
This command will display all the running containers
Then you could run the exec command which will allow you to enter inside a running container:
docker-compose exec irc
More about docker-compose up here: https://docs.docker.com/compose/reference/up/
Related
This question already has answers here:
Docker container will automatically stop after "docker run -d"
(22 answers)
Closed 10 days ago.
Given this simple Docker compose.yaml file:
services:
test:
image: node:18
website:
image: nginx
After running:
docker compose up
docker ps
I expected to see two running containers/images. Instead I got just the one:
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
c970ef47fb93 nginx "/docker-entrypoint.…" 51 seconds ago Up 48 seconds 80/tcp myid-website-1
What is happening here? Does Docker expect that a persistent process is kept running within the container image? How does it decide which services persist?
I also noticed that adding restart: always caused the Node image to perpetually restart. What would be a good way to get the Node image to start via Docker Compose, such that I could log into it via docker exec?
My instinct is that this has to do with the distinction between services and images/containers.
For a container to persist, it needs to run a program. When the program ends, the container is stopped.
The Nginx image runs the command nginx -g daemon off; which starts Nginx and then waits for requests to come in. It doesn't end.
The Node image runs the command node. When there's no arguments passed to it, it runs in interactive mode. But when you run it like you do, there's no TTY attached to the container, so node sees that there's no way to get any input. So node exits and the container is stopped.
If you run the command docker ps -a, you'll also see stopped containers. You'll then see that your node container has exited.
I am trying to run a container based on the debian:stretch image, but this does not work:
docker container run --detach debian:stretch
outputs:
7976eb7074289a741a2b183634345fc8519359cba4d543c03b0a6d4e5d7e0d53
And
docker ps -a
outputs:
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
7976eb707428 debian:stretch "bash" 3 seconds ago Exited (0) 2 seconds ago vigorous_lumiere
Whereas it works well with the latest nginx image:
docker run --detach nginx:latest
53ed18b5d1a7c72aa92bab0ca679269514db79f31a1d3759c2e25c7fdb1e82ff
docker ps -a
outputs:
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
53ed18b5d1a7 nginx:latest "nginx -g 'daemon of…" 2 seconds ago Up 2 seconds 80/tcp admiring_hawking
7976eb707428 debian:stretch "bash" About a minute ago Exited (0) About a minute ago vigorous_lumiere
Why does the container based on the debian:stretch image that I am instantiating does not work?
Does this come from the debian image?
I am running Docker version 18.09.1, build 4c52b90 on Ubuntu 16.04 LTS
Your container literally doesn’t do anything: it starts a shell, but since it’s running as a background process and doesn’t have anything on its stdin, it immediately exits.
You should read the official Docker tutorial on building and running custom images. Generally you should work by building your application into a custom image, setting up that image’s default CMD to run your application, and using docker build and docker run (or a tool like Docker Compose) to run the assembly. There’s not much point in running a plain Linux distribution container.
(Also remember that it’s extremely routine to docker rm containers, and so anything you do in an interactive shell in a container is very likely to get lost.)
(sorry using the term "kill" with quotes is not about docker-compose kill, is about "UNIX ps kill" after what the process really go out of the "UNIX ps list")
Usual docker run can be "killed" by usual docker stop, because after stop I not see the container at docker ps -a... If it is correct, there are a semantic bug with docker-compose because I can't "kill" the containers, they stay at docker ps.
After my simple docker-compose up (without &) I do ^C and the containers stay there at docker ps -a... Impossible to kill by docker compose stop.
NOTE: when I use ordinary docker run and after it docker stop there are nothing at docker ps -a, so I can say "I killed it".
Usual docker run can be "killed" by usual docker stop, because after stop I not see the container at docker ps.
No. docker stop just stops a running container, it doesn' t remove the container. This happens only in case you've used docker run --rm .... This --rm option means that when the container is stopped, it will be removed/deleted.
Docker
docker run ... creates and runs a container
docker stop ... stops a running container
docker start ... starts a stopped container
docker rm ... removes a stopped container
Docker Compose
docker-compose up creates and runs a collection of containers
docker-compose stop stops the containers
docker-compose start starts the containers
docker-compose down stops and removes the containers
Be careful...
As it discussed in the comments section, by using docker-compose down other things can also take place regarding volumes, networks. Keep in mind that you might lose data (if your container is a database for example) and make sure you have saved them or you are somehow able to create them again.
Check out running containers:
docker ps
Example output:
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
e86521d81a96 app_php "docker-php-entrypoi…" 2 hours ago Up About an hour 0.0.0.0:8080->80/tcp app_php_1
7a30681b6255 mysql:5.6 "docker-entrypoint.s…" 3 hours ago Up About an hour 0.0.0.0:3306->3306/tcp app_db_1
21aa3eef5f42 phpmyadmin/phpmyadmin "/run.sh supervisord…" 4 hours ago Up About an hour 9000/tcp, 0.0.0.0:8081->80/tcp app_phpmyadmin_1
9afc52b3f82f mailhog/mailhog "MailHog" 4 hours ago Up About an hour 1025/tcp, 0.0.0.0:8082->8025/tcp app_mailhog_1
then stop one by the container id:
docker kill part_of_the_id/name
For instance:
docker kill e86 or docker kill app_php_1
Docker-compose is just a script to help you manage one or multiple containers running in a group and is absolutely not required to manage your containers.
To remove the container completely you have to remove the container docker rm container_id_or_name
To stop all running containers:
docker stop $(docker ps -q)
You can use docker rm <container-name> to do that. This command will stop and remove service container. Anonymous volumes attached to the container will not be removed.
I'm new to docker.
I have an image that I want to run, but I want docker to see if that image is already running from another terminal...if it is running I don't want it to load another one...
is this something that can be done with docker?
if it helps, I'm running the docker with a privileged mode.
I've tried to search for singleton docker or something like that, but no luck.
updates-
1.working from ubuntu.
My scenario- from terminal X I run docker run Image_a
from terminal Y I run docker run Image_a
when trying to run from terminal Y, I want docker to check if there is already a docker running with Image_a, and the answer is true - I want docker not to run in terminal Y
You can use the following docker command to get all containers that running from specific image:
docker ps --filter ancestor="imagename:tag"
Example:
docker ps --filter ancestor="drone/drone:0.5"
Example Output:
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
3fb00087d4c1 drone/drone:0.5 "/drone agent" 6 days ago Up 26 minutes 8000/tcp drone_drone-agent_1
This approach uses docker api and docker daemon, so it doesnt matter if the run command executed in background or other terminal.
Aother approach:
If you have a single container form a single image:
Try naming your containers, You cant have 2 containers with the same name:
docker run --name uniquecontainer Image_a
Next time you run the above command you will get an error. Btw consider using -d so you dont have to switch terminals.
docker run -d --name uniquecontainer Image_a
By default docker leaves a bunch of dead volumes around.
$ docker ps -a
61e99f563834 jolly_swanson user/name:version "command" 52 seconds ago Exited (130) 51 seconds ago
Why doesn't docker run jolly_swanson restart that container with its old data? I feel like I must be missing something from the documentation.
You seem to be confusing images and containers. Docker leaves dead containers around, not images (and not volumes either).
docker run creates a new container from an existing image. So docker run jolly_swanson does not work because jolly_swanson is the name of a container, not an image.
To start an existing container, use start, e.g. docker start jolly_swanson.