In the previous blog we presented our analysis of image update frequency for official DockerHub images and the implications for application images built on top of these base images. It was pointed out in a Reddit reply by /u/AskOnDock29 that users can update the operating system packages in the images themselves, independently of the official image and so the frequency, or infrequency, of base image updates is not a concern since this is easily manageable by end-users.
In our last blog, we reported on operating systems usage on DockerHub, focusing on official base images.
Most users do not build their container image from scratch they built on top of these base images, for example extending an image such as library/alpine:latest with their own application content.
Whenever one of these base OS images is updated, images built on top are typically rebuilt in order to inherit the fixes included in the base image. In this blog, we will be looking at the update frequency of base images: frequency of updates, changes made and how that impacts end users.