hilscher NIOT-E-TPI51-EN-RE User Manual page 216

Isolated application execution with Docker
Edge Gateway | NIOT-E-TPI51-EN-RE (Connect)
DOC170502UM07EN | Revision 7 | English | 2019-07 | Released | Public
Image
An image is the basis for a container and includes only its program code
and basic settings.
It does not include information the program code generates on a storage
medium or RAM while it is running.
Moreover, it does not include any information on the environment the image
is to be executed in, i.e. it is platform-neutral.
An image always relates to the defined processor architecture it is compiled
for, e.g. x86, x64 or ARM. If a container is generated from an image, make
sure that the image is suitable for the hardware platform used.
Note:
For more information on images, see the Docker documentation
https://docs.docker.com/engine/
https://docs.docker.com/glossary/?term=image.
Container
A container is a runtime instance of an image.
A container represents an image being executed within an individual
runtime environment of its own, comparable to a running process. Running
an image in a container is commonly denominated as "starting" the
container. The term "starting" implies that Docker transfers the image to an
individual runtime environment to execute it there. This runtime
environment is isolated both against the host machine and against the
other containers present on this host machine. Access to resources of the
host system as e.g. host files and ports only occurs, if explicitly configured.
A container consists of:
a Docker image,
·
a runtime environment, and
·
a standard command architecture.
·
The runtime environment contains e.g. current information on configuration
and status. For storing this information, Docker generates a virtual drive in
the container, a so-called "volume"
Docker can start several containers, even containers originating from the
same image.
Note:
For more information on containers, see the Docker documentation
(https://docs.docker.com/get-started/#prerequisites) and, in
particular, its glossary
term=container).
and, in particular, its glossary
(https://docs.docker.com/glossary/?
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