Acquire interactive shell in Packer?

Question

I'm trying to create a Packer AMI image for EC2 based off of CentOS 7. I'm able to get provisioning working just fine, I can upgrade and install packages without a hitch.

The problem I'm having is that the Docker daemon won't start, and I need it running at build time to be able to bake some Docker images onto the machine.

Is there a way to acquire an interactive shell to the EC2 build instance during the Packer build so I can debug what is going wrong with it? Until I figure out what is failing, I can't finish my work on this AMI.

I've never had the need to do so, but can't you just add one sleep 1200 into provision script, and ssh into instance while it is waiting? — Dusan Bajic

Naftuli Kay Naftuli Kay · Accepted Answer · 2015-12-31T00:23:12

Pass the -debug option to packer build:

packer build -debug something.json

This will cause packer to pause between steps, emit an IP address and a generated PEM certificate.

You can then do ssh -i ec2_generated_key.pem centos@IP and get into the box.

Acquire interactive shell in Packer?

1 Answers