Docker is a platform that allows developers to easily create, deploy, and run applications in containers. Containers are a way to package software so that it can run consistently across different environments, like your computer, a server, or even the cloud.

Containers are lightweight, efficient, use less resources than traditional VMs and shares the host system’s kernel and libraries.

To update a docker container or a docker compose stack, you need to pull the new version (image) from Docker Hub or any other container registery and re-create the container using the new image. Container data found in volumes will not be lost during container re-creation. Follow these steps to update any docker container or stack.

Update single Docker container

1. Pull the new image using docker pull. You can download specific version by adding its tag to the image name mysql:8.1.0, or don’t specify a version to download latest:

docker pull louislam/uptime-kuma

2. Stop then remove the existing running container:

docker container stop uptime-kuma
docker container rm uptime-kuma

3. Re-create the container:

docker run -d --restart=always -p 3001:3001 -v uptime-kuma:/app/data --name uptime-kuma louislam/uptime-kuma

• If you forgot the docker run command you used to create the original container, search for it in the terminal history:

history | grep "docker run"

Update Docker compose stack

1. Navigate to the directory where the stack .yaml file is located:

cd /home/elastic/docker

2. Pull the new images from the yaml file. By default this command will use docker-compose.yaml:

docker compose pull

3. Re-create the containers using the up command, in detached mode:

docker compose up -d

• If you are using a yaml file with a different name than docker-compose.yaml, make sure to specify the file name using the -f flag:

docker compose -f pi.yaml pull

[+] Pulling 1/1
 ✔ pihole Pulled                                                                                                   0.5s

docker compose -f pi.yaml up -d

[+] Running 1/1
 ✔ Container pihole  Started                                                                                       5.3s

• If you want to force Compose to stop and recreate all containers, use the --force-recreate flag:

docker compose up -d --force-recreate

From July 2023 Compose V1 stopped receiving updates. It’s also no longer available in new releases of Docker Desktop.

Optional: delete old images to free disk space

1. List docker images:

docker image ls

REPOSITORY             TAG       IMAGE ID       CREATED        SIZE
louislam/uptime-kuma   latest    fb3a3565b2da   5 days ago     431MB
louislam/uptime-kuma   1         c75c443c4b9a   7 weeks ago    484MB
pihole/pihole          latest    566a5a3d4773   2 months ago   301MB
pihole/pihole          <none>    4d6ef5c6684a   5 months ago   324MB

2. Delete one or multiple images using the first few unique letters of the IMAGE ID:

docker image rm c75 4d

Untagged: louislam/uptime-kuma:1
Untagged: louislam/uptime-kuma@sha256:0b55bcb83a1c46c6f08bcc0329fc6c1d86039581102ec8db896976a9d46de01d
Deleted: sha256:c75c443c4b9afc5b3bed698692c96318e45413c8ab866b5864432ae7e522185b
Untagged: pihole/pihole@sha256:a74dde4800f54d3c0b0839babbac9f2cc7e4b8239ab4a5bc2c25c7328ec1c019
Deleted: sha256:4d6ef5c6684a8f5ce05e684dd1b92d75dfb1bbfeec2b8cf9a475fdbe71de2f07

3. Verify unused images are deleted:

docker image ls
REPOSITORY             TAG       IMAGE ID       CREATED        SIZE
louislam/uptime-kuma   latest    fb3a3565b2da   5 days ago     431MB
pihole/pihole          latest    566a5a3d4773   2 months ago   301MB

Video Guide

Further reads

• Docker run documentation
• Docker compose documentation
• Difference between “docker compose” and “docker-compose”
• Migrate compose to v2