Thanks to the bitcoin.stack community I have successfully launched a bitcoind docker with an external volume which has the block data
Currently its in 100% sync but I am facing an issue to get information using bitcoin-cli I need to run bitcoind -reindex and then add txindex=1 into bitcoin.conf
As I pulled the docker image from docker hub I do not have any control over its docker file and I have 140GB+ blockchain data that I do not wanna discard and start over
How do I run --reindex on an docker container ?
While your container is running you can run docker exec -it <mybitcoindcontainer> /bin/sh. This should give you a shell inside your running container. You can then run your choice of commands at the shell prompt.
Related
I'm building an app that makes api calls to run code inside docker containers
I want to run a docker container that has docker running inside it.
I want to create a docker file that pulls other docker images inside it and then waits for api calls (on port 2376) to create, run and delete containers based on the docker images that i pulled into the dockerfile
This is the dockerfile I'm trying to create right now.
FROM docker:stable
RUN docker pull python
EXPOSE 23788
CMD tail -f /dev/null
However when the RUN command is issued i get this error message:
docker: Cannot connect to the Docker daemon at unix:///var/run/docker.sock. Is the docker daemon running?
I don't really know how to start docker inside a docker container.
The reason i need this kind of a docker file is so that i can then use kubernetes to scale this part of my application
There's a special image for this, docker:dind. See the bit about "Docker in Docker" in https://hub.docker.com/_/docker.
I created a task definition on Amazon ECS and want to run in with Fargate. I set up my task, network mode is awsvpc. I created a new container with a docker image (simple "Hello world" project) on Amazon ECR. Run the task - everything works fine. Now I need to run a docker container from hub.docker.com as a part of the task
Dockerfile
FROM ubuntu
RUN apt-get update && apt-install ...
ADD script.sh /script.sh
RUN chmod +x /script.sh
ENTRYPOINT ["/script.sh"]
script.sh
#!/bin/bash
...prepare data
docker run -rm some_container_from_docker_hub
...continue process data
Initially, I got "command not found" error. OK, I installed docker into my image. Now I've got "Cannot connect to the Docker daemon".
My question: is there any way to run a docker container inside of another docker container on Amazon Fargate?
You can't run a container from another container using Fargate.
Running a container from another one, like in your case, would mean that you could have access to the docker daemon. Accessing the docker daemon means root access to the host machine. This breaks the docker container isolation and is unsafe.
Depending on your usage, I suggest you use an EC2 instance, use CodeBuild or build an operator that is able to talk with the api to span containers.
[Edit]: It seems that there is an open issue on this topic [ECS,Fargate]: Support for building Docker containers #95
If command "docker run ubuntu bash" the container won't last.
but if I command "docker run -it ubuntu bash"
the container will make a pseudo-tty and keep this container alive.
my question is
is there any way I can make a Dockerfile for building an image based on ubuntu/centos then I just need to command "docker run my-image" and
the container will last.
apologize for my poor english, I don't know if my question is clear enough.
thanks for any response
There are three ways to run containers:
task containers - do one thing and then exit, like docker run ubuntu ls /
interactive containers - open a connection to the container with -it, like docker run -it ubuntu bash
background containers - keep a container running detached in the background with -d, like docker run -d ubuntu:14.04 ping localhost
Docker keeps the container running as long as there is an active process in the container. The first container exits when the ls command completes. The second container will exit when you exit the bash session. The third container will stay running as long as the ping process keeps running (note that ping has been removed from the recent Ubuntu images, which is why the example specifies 14.04).
In practice to start a container I do:
docker run a8asd8f9asdf0
If thats the case, what does:
docker start
do?
In the manual it says
Start one or more stopped containers
This is a very important question and the answer is very simple, but fundamental:
Run: create a new container of an image, and execute the container. You can create N clones of the same image. The command is:
docker run IMAGE_ID and not docker run CONTAINER_ID
Start: Launch a container previously stopped. For example, if you had stopped a database with the command docker stop CONTAINER_ID, you can relaunch the same container with the command docker start CONTAINER_ID, and the data and settings will be the same.
run runs an image
start starts a container.
The docker run doc does mention:
The docker run command first creates a writeable container layer over the specified image, and then starts it using the specified command.
That is, docker run is equivalent to the API /containers/create then /containers/(id)/start.
You do not run an existing container, you docker exec to it (since docker 1.3).
You can restart an exited container.
Explanation with an example:
Consider you have a game (iso) image in your computer.
When you run (mount your image as a virtual drive), a virtual drive is created with all the game contents in the virtual drive and the game installation file is automatically launched. [Running your docker image - creating a container and then starting it.]
But when you stop (similar to docker stop) it, the virtual drive still exists but stopping all the processes. [As the container exists till it is not deleted]
And when you do start (similar to docker start), from the virtual drive the games files start its execution. [starting the existing container]
In this example - The game image is your Docker image and virtual drive is your container.
run command creates a container from the image and then starts the root process on this container. Running it with run --rm flag would save you the trouble of removing the useless dead container afterward and would allow you to ignore the existence of docker start and docker remove altogether.
run command does a few different things:
docker run --name dname image_name bash -c "whoami"
Creates a Container from the image. At this point container would have an id, might have a name if one is given, will show up in docker ps
Starts/executes the root process of the container. In the code above that would execute bash -c "whoami". If one runs docker run --name dname image_name without a command to execute container would go into stopped state immediately.
Once the root process is finished, the container is stopped. At this point, it is pretty much useless. One can not execute anything anymore or resurrect the container. There are basically 2 ways out of stopped state: remove the container or create a checkpoint (i.e. an image) out of stopped container to run something else. One has to run docker remove before launching container under the same name.
How to remove container once it is stopped automatically? Add an --rm flag to run command:
docker run --rm --name dname image_name bash -c "whoami"
How to execute multiple commands in a single container? By preventing that root process from dying. This can be done by running some useless command at start with --detached flag and then using "execute" to run actual commands:
docker run --rm -d --name dname image_name tail -f /dev/null
docker exec dname bash -c "whoami"
docker exec dname bash -c "echo 'Nnice'"
Why do we need docker stop then? To stop this lingering container that we launched in the previous snippet with the endless command tail -f /dev/null.
daniele3004's answer is already pretty good.
Just a quick and dirty formula for people like me who mixes up run and start from time to time:
docker run [...] = docker pull [...] + docker start [...]
It would have been wiser to name the command "new" instead of "run".
Run creates a container instance of an existing (or downloadable) image and starts it.
I'm trying to run Docker inside a Jenkins container that is also running in Docker (i.e. Docker in Docker). What I want to know is how to properly start the Docker service when booting Jenkins. The only solution I've found today is to build my own Jenkins image based on the official Jenkins image but change the jenkins script loaded by the entry point to also start up Docker:
# I've added this line just before Jenkins is started from the script:
sudo service docker start
# I've also removed "exec" from the original file which used "exec java $JAVA_TOPS ..." but that didn't work
java $JAVA_OPTS -jar /usr/share/jenkins/jenkins.war $JENKINS_OPTS "$#"
This works when I run (using docker run) a new container but the problem is that if I do (docker start) on stopped container the Docker service is not started.
I strongly suspect that this is not the right way to start my Docker service. My plan is to perhaps use supervisord to start Jenkins and Docker separately (I suppose container linking is out of the question since Docker should be executed as a service on the same container that Jenkins is running on?). My concern with this approach is that I'm going to lose the EntryPoint specified in the Jenkins Dockerfile which allows me to pass arguments to the Jenkins container when starting the container, for example:
docker run -p 8080:8080 -v /your/home:/var/jenkins_home jenkins -- <jenkins_arguments>
Does anyone have any recommendations on a good way to solve this preferably by not forking the official Jenkins image?
I'm pretty you cannot do that.
Docker in Docker doesn't mean you have to run docker inside docker with 3 level : host > First level container > Second Level Container
In fact, you just need to share docker with host, and this is your host who will run others containers.
To do that, you have to mount volume with -v parameter
-v /var/run/docker.sock:/var/run/docker.sock
with this command, when you will docker run inside you jenkins container, the docker client will communicate with docker deamon from your host in order to run new container.
To do that, you should run your jenkins container with privileged
--privileged
To resume, here is the full command line
docker run -d -v /var/run/docker.sock:/var/run/docker.sock --privileged myimage
And you you don't need to create a new jenkins image for that.
Hoping to have helped you
http://container-solutions.com/running-docker-in-jenkins-in-docker/