CODEWITHSUNDEEP
docker
gremo
gremo

Reputation: 48439

When I push a image to Docker Hub... does the image is a "snapshot" of all customizations.. or is created again when you pull/run it?

Learning Docker here... I have a simple question. I can't figure out the following.

Today, Alice build and push her custom image to Docker Hub:

FROM alpine

RUN apk add --update --no-cache mysoftware

When Alice build the image, mysoftware (say version 1.0) will be added to the image.

Next week, Bob pull the image. In the meanwhile, mysoftware has bumped to 1.1 version. Does bob gets the updated version of mysoftware... or the apk add mysoftware command is "freezed" at the time that Alice build/push the image?

Upvotes: 0

Views: 142

Answers (1)

ISanych
ISanych

Reputation: 22710

When you build your image docker is using sha256 code of base image, so even if tag of your base image (alpine:latest in your case) will point on different image - your container will still be using exactly the same image it was using during creation. Only docker build is creating new image, push and pull will only transfer earlier built image.

If you want to update your image you'll have to do docker build and docker push again

Upvotes: 2

Related Questions