Docker image of 32 bit Ubuntu

Question

1. I am looking a lightweight docker image with Ubuntu 32 bit. Where can I find it?

2. When I put a command docker build . in my directory with Dockerfile I get output like:

ending build context to Docker daemon 10.21 MB
 Step 1 : FROM ubuntu
  ---> 104bec311bcd
 Step 2 : ENV x /home/
  ---> Using cache
  ---> e38b022c91f8
 Step 3 : COPY ./x /home
  ---> Using cache
  ---> c4558c94236f

What does those "hashes" means? I mean for example c4558c94236f. And what about when it comes to cache?

Answer 1

You can find in the Docker Hub various 32 bits docker images, for example

https://hub.docker.com/r/32bit/ubuntu/

You can learn how to do it yourself with

http://mwhiteley.com/linux-containers/2013/08/31/docker-on-i386.html

About the hashes, you should read

https://docs.docker.com/engine/userguide/storagedriver/imagesandcontainers/