I use google deployment manager to create:

• an instance template
• an instance group manager
• an autoscaler

This works like a charm (I used this tutorial). However, I fail to define an instance template that runs a docker container (fwiw: the google cloud web console looks as that when one creates such an instance template).

I tried several things (some might be dumb):

1. Take a look at the description of the working instance template and try to reproduce it.

   • use command gcloud compute instance-templates describe <working-template> to get an extensive definition of the working instance template
   • Define an instance template that matches the working instance template
   • Do a test deploy
   • SSH into spawned instance, confirm that target image is not pulled

2. Do not use Container-Optimized OS (aka. copy this example )

   • In the yaml replace spec containers image by my gcr.io hosted docker image.
   • Do a test deploy.
   • SSH into spawned instance, confirm that target image is not pulled.

3. Confirm that something is wrong with previous approaches: get the gcloud console util command, duplicate the working instance template. Update the deployment so that the instance group uses this manually copied instance template.

   • Do a test deploy.
   • SSH into spawned instance, confirm that target image is not pulled.

4. Confirm that the google deployment manager is not messing around.

   • Update the deployment so that the instance group uses the working instance template.
   • Do a test deploy.
   • SSH into spawned instance, confirm all works as expected.

Am I going in the wrong direction here ?