44_update_container_config.md

Update a Container Configuration

Docker Documentation References:

docker update

docker run

docker stop

docker rm

Intent

The intent of this kata is to understand how to update a containers configuration.

Overview

In this exercise we will create a container, show the containers stats at runtime, modify its settings, then show the containers stats again. Finally, we will stop and remove the container.

Kata Steps

Create a Container

Command

docker run -p 80:80 -d nginx:alpine

Output

/ # docker run -p 80:80 -d nginx:alpine
19d948bb72d5984ae6f167a784bc661fc9ada8bf3706b73d0c52b9c609f85e71

Show Stats

Command

docker stats --no-stream

Output

/ # docker stats --no-stream
CONTAINER           CPU %               MEM USAGE / LIMIT       MEM %               NET I/O             BLOCK I/O           PIDS
19d948bb72d5        0.00%               1.676 MiB / 1.952 GiB   0.08%               578 B / 578 B       0 B / 0 B           2

Update the Container Configuration

Command

docker update --memory 1Gb --memory-swap 1Gb $(docker ps -aq)

Output

/ # docker update --memory 1Gb --memory-swap 1Gb $(docker ps -aq)
19d948bb72d5

Show Stats

Command

docker stats --no-stream

Output

/ # docker stats --no-stream
CONTAINER           CPU %               MEM USAGE / LIMIT   MEM %               NET I/O             BLOCK I/O           PIDS
19d948bb72d5        0.00%               1.656 MiB / 1 GiB   0.16%               648 B / 648 B       0 B / 0 B           2

Stop the Container

Command

docker stop $(docker ps -aq)

Output

/ # docker stop $(docker ps -aq)
19d948bb72d5

Remove the Container

Command

docker rm $(docker ps -aq)

Output

/ # docker rm $(docker ps -aq)
19d948bb72d5

Previous | Index | Next