persist changes to container

How to persist changes to a container If I were to modify files in say zenmodeler, then they are not visible to other containers and is lost after service restart. This needs to be saved to the original image, or somehow a snapshot of this container filesystem had to be synced to all other containers. Is there a method to do this Can you please provide details of how it can be done

I manually create a docker container based on the zenoss core image and try updating.
But zenoss settings are different while being spawned by serviced, so for example, python files go to /usr/lib/python2.7 path, which is not visible from within zenoss which looks at /opt/zenoss. That was one example though.

So, it is being tedious to sync changes on filesystem to all containers and error prone currently.
Can someone please detail the method to this madness.

Your help much appreciated.

Thanks,
LN