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Need help in understanding how docker communication happens - via logs

Need help in understanding how docker communication happens - via logs

Is there any doc/article describes about how we can trace a user activity in docker infra.
Lets say i have run “docker run ubuntu”.
docker service talks to registry -> then download image -> run container -> exit container
There are many backend calls gets triggered for this operation and travels through multiple services
cli -> dockerd -> containerd -> runc etc
Now , how/where can i find these Rest API/grpc calls .
This way i can trace all details

I am using centos and checked in “journalctl -f” and “journalctl -u docker -f” , however dont have much info.

Anyone to help?

Your “Title” is a bit misleading … as this is more a “user management” topic rather than a intercommunication issue :wink:

However, to answer your question: Afaik It’s almost impossible to do this with the CE (Community Edition) as all docker operations are ment to be executed as “root”. Of course you can “brew” some user and rights management on your own … but you’ve to decide if it’s worth the effort.

So maybe you’re better off with the “Docker Enterprise” solution which offers a full user management -> https://docs.docker.com/ee/ & https://docs.docker.com/ee/ucp/

I think the emphesis is on “how to trace how docker tigger the apis” and not the user management per se.
As a slimed down information, you can check the docker events to see when an image is pulled, a container is created or deleted and more. If you realy want to act on the events, you will need to use a docker-api sdk for the programming language of your choice and develop it. Though, this will not result in a tracable sequence with all api calls to endpoints and the content they send to them.