Cloud-init per-boot script doing nothing

Question

I am new to cloud-init, my final goal is to run an R script each time an EC2 Spot Instance becomes active, but in order to test it I created an on-demand Ubuntu 12.04 instance and created a simple script but nothing happens after reboot. Here are the steps I took:

• Launched the new Ubunut 12.04 instance
• Navigate to /var/lib/cloud/scripts/per-boot
• sudo vi script.sh
• Added the following code:

#!/bin/sh
echo "test"

• sudo reboot

At this point I thought I should see a "test" print when the instance reboots, but there is nothing there. I went to take a look at /var/log/cloud-init.log but there is no error or anything out of the ordinary.

I am clearly missing something so any tip in the right direction will be much appreciated!

Thanks!

Answer 1

It won't run unless the scripts user is set to always run. See this answer for more details (and for instructions on how to get scripts to run on reboot, generally).

Answer 2

If we want to debug the user-data in cloud-init, we can try the following steps:

1. rm -rf /var/lib/cloud/*
2. cloud-init init
3. cloud-init modules -m final

With above commands, the cloud-init is re-run. And we can check the cloud-init.log under /var/log/cloud-init.log to check if it is successfully exec.

Answer 3

Looked at the source code, the script must be executable. This'll make it work

sudo chmod 744 script.sh