How to dynamically add ports to Docker without rebuilding the image

Sometimes you may need to modify or add exposed ports to a Docker container during operation, but sometimes you don't want to create a new image for the running container. At this time, you can find the storage location of the docker container and then modify the configuration file directly.

Our containers are all stored in /var/lib/docker/containers下.

My container is at /var/lib/docker/containers/797f3d0cb82aec7d1c355c7461b5bc5a050c1c0cbbe5d813ede0edad061e6632

Each container ID corresponds to a hash_id. You can see that the nginx container exposes two ports. Next, let's add another port 9999.

Enter the directory corresponding to the container:

cd /var/lib/docker/containers/797f3d0cb82aec7d1c355c7461b5bc5a050c1c0cbbe5d813ede0edad061e6632

We see:

Copy hostconfig.json and use the json conversion tool to find the "PortBindings" node

Next we will add one on top by following the same pattern.

As shown in the figure:

Modify hostconfig.json and save.

Then modify config.v2.json的ExposedPorts , as shown in the figure:

Save and exit.

Restart Docker,

Restart the container.

As you can see, port 9999 has been exposed.

Summarize

The above is the method that I introduced to you to dynamically add ports to Docker without re-building the image. I hope it will be helpful to you. If you have any questions, please leave me a message and I will reply to you in time. I would also like to thank everyone for their support of the 123WORDPRESS.COM website!
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