Question

I am attempting to load user data into an Ubuntu 12.04 LTS AMI (ami-a29943cb, but I’ve tried a few others to no avail) via boto’s ec2.run_instances(…, user_data=USER_DATA). Similarly, I have had no success with manually supplying the user data while launching the instances via the AWS console. There are no results or messages in /var/logs/syslog for any of the methods I’ve tried.

USER_DATA looks something like the following, read in as a string from a file:

#!/usr/bin/env python

import boto

AWS_BOOTSTRAP_BUCKET  = ''
AWS_ACCESS_KEY_ID     = ''
AWS_SECRET_ACCESS_KEY = ''

# Pull processing script from S3.
print 'Bootstrapping started.....'
print 'Connecting to S3...'
s3     = boto.connect_s3(AWS_ACCESS_KEY_ID, AWS_SECRET_ACCESS_KEY)
bucket = s3.get_bucket(AWS_BOOTSTRAP_BUCKET)
print 'Downloading bootstrap file...'
key    = bucket.get_key('xxx')
key.get_contents_to_filename('xxx')

print 'Importing Bootstrap file...'
import xxx
xxx.process()

# Shut down the EC2 instance running this process.
print 'Shutting down this instance...'
import socket
desired_hostname = socket.gethostname()
ec2 = boto.connect_ec2(AWS_ACCESS_KEY_ID, AWS_SECRET_ACCESS_KEY)
reservations = ec2.get_all_instances()
for reservation in reservations:
    for instance in reservation.instances:
        if desired_hostname in instance.private_dns_name:
            instance.terminate()

I have furthermore tried uploading the file to a public S3 bucket and loading it in this manner, once again to no avail:

#include
https://s3.amazonaws.com/bucket/file.py

Does anyone have any advice in this regard? Am I completely misunderstanding the purpose of user-data/cloud-init or is the technology merely broken in the AMI I am trying to utilize?

Answer 1

It’s hard to know what happened without an error message, but there are a few places you can look:

1. The file /var/log/cloud-init.log will usually contain any errors (e.g. boto import failure) that occurred during instance bootstrapping.
2. The directory /var/lib/cloud/instance will contain the raw scripts and user-data downloaded to the instance
3. You can View/Edit USER_DATA inside the AWS console by right-clicking the instance, to see if boto populated it correctly.

Looking in those places should help provide clarity.

I know Ubuntu 12.04 comes with boto 2.2.2:

root@vanilla-562c:/var/lib/cloud/instance# python
Python 2.7.3 (default, Apr 20 2012, 22:44:07) 
[GCC 4.6.3] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> import boto
>>> boto.__version__
'2.2.2'

..but I wonder if it’s actually accessible in your PYTHONPATH at runtime.