While docker is all the rave, and for good reason, it is not without its drawbacks. One of the primary reasons we use Docker is to get more done with less work, but there are times when the boxed solution you have found does not work. Fortunately, we can easily take a broken Docker image and fix it up into shape.

Fix a Bad Image

Dockerfile to the rescue!

Use a Dockerfile to create a new image as an extension of the original:

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# extend the broken image with your patches
FROM broken/image
# patch up the original
RUN touch /that/missing/file
RUN chmod -R user:user /home/user

Build a replacement image!

% docker build -t <tag> .
Sending build context to Docker daemon  2.56 kB
Sending build context to Docker daemon
Step 0 : FROM broken/image
 ---> 78ee0694f929
Step 1 : RUN touch /that/missing/file
 ---> Running in 78ee0694f929
 ---> ade3d87907de
Step 2 : RUN chown -R user:user /home/user/
 ---> Running in ade3d87907de
 ---> f1cdcfa9ffb8
Removing intermediate container ade3d87907de
Successfully built f1cdcfa9ffb8

Run with your new image!

% docker run -p 8080:8080 <tag>