Lab 3.4 in CKAD class ask to find multi container pod yaml in the official documentation

alexanderlvov1

Is there really a clean working example of that? i mean i found one with shared volume, that use nginx and debian and that probably belong in a later chapter. Then i found one with sidecars but i believe that too belongs in a later chapter. Then i found one with custom images but it doesnt work unless created custom images. Which one is that i am supposed to have found and bookmarked?

chrispokorni

Hi @alexanderlvov1,

Multi-container pods have various use cases.
The example pod with nginx and debian containers is a working use case for situations when one container (debian) is used as an update interface to control content and/or the environment of the second container (nginx).
Sidecars have many use cases as well. In exercise 2.4 a simple working example is presented with nginx and fluentd containers. As shown, it only runs the two distinct containers in the pod, however, in a later chapter the fluentd container is fully configured to manage the logs of the nginx container.
Metrics collection is another use of the sidecar multi-container pattern.
Whether predefined container images or custom container images are used in a multi-container pod, their purpose is to allow the containers to interact with each other, either through a shared process namespace, the shared network namespace, shared volume device, etc.

Regards,
-Chris

alexanderlvov1

Hi Chris. Thanks you for answering the question, but my question is rather an applied or practical question concerning the course material. I would like to follow course material diligently and i was just not able to find an simple multicontainer definition that works on my GKS. So i was wondering if there is a discrepancy between material and official documentatiton.

chrispokorni

Hi @alexanderlvov1,

Have you tried running the simple two-container pod from lab 2.4? What was the outcome of that exercise?

Regards,
-Chris