i have a running Mongo DB Container called xyz from offical Mongo Image. i created the container with docker run -d -p 21707:21707 mongo
In this container i created 2 collections with sample data.
Now i want to extract this container in a new image on dockerhub.
I used docker commit and created a new image, pushed it on the docker hub. If i pull the image on a other system and create a new container from this image, there are no data like in my origin container xyz.
After research i found out that the mongo image could used with a volume, but i missed this step in the past... I think the container use /data/db as standard volume(docker inspect), on commit this volume is not attached to the new image?!
Also i tried docker export/import with the same problem mentioned above!
Now my Question, how could i reach to migrate this "xyz" running container with my sample data in a new image/container?
Thanks a lot!
I used docker commit and created a new image, pushed it on the docker hub. If i pull the image on a other system and create a new container from this image, there are no data like in my origin container xyz.
The mongo docker image writes its data into a volume. As a result, those data won't be saved to a new docker image created with docker commit. docker export won't produce your data for the same reason.
how could i reach to migrate this "xyz" running container with my sample data in a new image/container?
What you want is either:
- create a new container re-using the first container's volume → see
--volumes-from
- save the first container's volume data into a directory on your docker host, and create a new container mounting this directory into the container → the
docker run -v option
Also, this SO question might help you figure out volumes.
I wanted to make an image to test things around authentication and I has the same issue. I solved it this way:
Dockerfile
FROM mongo
COPY setup.sh /
RUN chmod +x /setup.sh
RUN /setup.sh
ENTRYPOINT ["/usr/bin/mongod"]
CMD ["--auth", "--dbpath=/containerdb"]
setup.sh
#!/bin/bash
mkdir containerdb
mongod --auth --dbpath=/containerdb &
until mongo admin --eval 'db.createUser({"user":"root", "pwd":"password", "roles": [ "root" ] })'
do
echo 'Mongo not yet ready, waiting 1 sec until retry'
sleep 1
done
mongod --shutdown --dbpath=/containerdb
Bim! When you run this image you have a mongodb with authentication activated and a root user.
The key is to workaround the VOLUME in the base Dockerfile by storing the data somewhere else.
