Multicontainer Update

Product support
1

We just switched over to multicontainer builds (amazing work on this all btw), and we have generally positive feelings.

There is one slightly annoying thing that I wanted to report, specifically for us the two running containers are functionally identical, but have different entry points within the application. This works great in practice, but when it is time to update, it downloads two separate images for the update, which is a little bit funny to think about.

Is there any way to work around this? In practice it takes us 2x the time to update now because we have to wait for a duplicitave download…

3

Hi @mattyg, Do these two container differ in their entry point script and other layers are same? If it is such a case you can extract the command out to use the same image. Example below:

version: '2'
services:
  web:
      build: ./docker    # common Dockerfile
      image: IMAGENAME
      ports:
          - "8090:8090"
      command: ["serve"]

  worker:
      build: ./docker    # common Dockerfile
      image: IMAGENAME   # reuse image
      ports:
          - "8091:8090"
      command: ["work"]
5

Ah ha. I wasn’t specifying the image name. I will give that a go, then report back.

7

Sounds good! Looking forward to hearing if this resolves the problem :+1: