Adaface Sample Docker Questions

Check the following Dockerfile used for a project (STAGE 1):

We created an image from this Dockerfile on Dec 14 2021. A couple of weeks after Dec 14 2021, Ubuntu released new security updates to their repository. After 2 months, we modified the file (STAGE 2):

Couple of weeks later, we further modified the file to add a local file ada.txt to /ada.txt (STAGE 3): (Note that ada.txt exists in /home/adaface and the dockerfile exists in /home/code folders)

Pick correct statements:
            
            A: If we run “docker build .” at STAGE 2, new Ubuntu updates will be fetched because apt-get update will be run again since cache is invalidated for all lines/layers of Dockerfile when a new line is added.
            B: If we run “docker build .” at STAGE 2, new Ubuntu updates will not be fetched since cache is invalidated only for last two lines of the updated Dockerfile. Since the first two commands remain the same, cached layers are re-used skipping apt get update.
            C: To skip Cache, “docker build -no-cache .” can be used at STAGE 2. This will ensure new Ubuntu updates are picked up.
            D: Docker command “docker build .” at STAGE 3 works as expected and adds local file ada.txt to the image.
            E: Docker command “docker build .” at STAGE 3 gives an error “no such file or directory” since /home/adaface/ada.txt is not part of the Dockerfile context.

Review the following Dockerfiles that work on two projects (project and project2):

All Docker files have the same end result:
            
            - ‘project’ is cloned from git. After running few commands, ‘project’ code is removed.
            - ‘project2’ is copied from file system and permissions to the folder is changed.

Pick the correct statements:
            
            A: File 1 is the most efficient of all.
            B: File 2 is the most efficient of all.
            C: File 3 is the most efficient of all.
            D: File 4 is the most efficient of all.
            E: Merging multiple RUN commands into a single RUN command is efficient for ‘project’ since each RUN command creates a new layer with changed files and folders. Deleting files with RUN only marks these files as deleted but does not reclaim disk space. 
            F: Copying ‘project2’ files and changing ownership in two separate commands will result in two layers since Docker duplicates all the files twice.