user-data (cloud-init) script not executing on EC2

Question

my user-data script

#!
set -e -x
echo `whoami`
su root
yum update -y
touch ~/PLEASE_WORK.txt

which is fed in from the command:

ec2-run-instances ami-05355a6c -n 1 -g mongo-group -k mykey -f myscript.sh -t t1.micro -z us-east-1a

but when I check the file /var/log/cloud-init.log, the tail -n 5 is:

[CLOUDINIT] 2013-07-22 16:02:29,566 - cloud-init-cfg[INFO]: cloud-init-cfg ['runcmd']
[CLOUDINIT] 2013-07-22 16:02:29,583 - __init__.py[DEBUG]: restored from cache type DataSourceEc2
[CLOUDINIT] 2013-07-22 16:02:29,686 - cloud-init-cfg[DEBUG]: handling runcmd with freq=None and args=[]
[CLOUDINIT] 2013-07-22 16:02:33,691 - cloud-init-run-module[INFO]: cloud-init-run-module ['once-per-instance', 'user-scripts', 'execute', 'run-parts', '/var/lib/cloud/data/scripts']
[CLOUDINIT] 2013-07-22 16:02:33,699 - __init__.py[DEBUG]: restored from cache type DataSourceEc2

I've also verified that curl http://169.254.169.254/latest/user-data returns my file as intended.

and no other errors or the output of my script happens. how do I get the user-data scrip to execute on boot up correctly?

Answer 1

Cloud-init does not accept plain bash scripts, just like that. It's a beast that eats YAML file that defines your instance (packages, ssh keys and other stuff).

Using MIME you can also send arbitrary shell scripts, but you have to MIME-encode them.

$ cat my-boothook.txt
#!/bin/sh
echo "Hello World!"
echo "This will run as soon as possible in the boot sequence"

$ cat my-user-script.txt
#!/usr/bin/perl
print "This is a user script (rc.local)\n"

$ cat my-include.txt
# these urls will be read pulled in if they were part of user-data
# comments are allowed.  The format is one url per line
http://www.ubuntu.com/robots.txt
http://www.w3schools.com/html/lastpage.htm

$ cat my-upstart-job.txt
description "a test upstart job"
start on stopped rc RUNLEVEL=[2345]
console output
task
script
echo "====BEGIN======="
echo "HELLO From an Upstart Job"
echo "=====END========"
end script

$ cat my-cloudconfig.txt
#cloud-config
ssh_import_id: [smoser]
apt_sources:
 - source: "ppa:smoser/ppa"

$ ls
my-boothook.txt     my-include.txt      my-user-script.txt
my-cloudconfig.txt  my-upstart-job.txt

$ write-mime-multipart --output=combined-userdata.txt \
   my-boothook.txt:text/cloud-boothook \
   my-include.txt:text/x-include-url \
   my-upstart-job.txt:text/upstart-job \
   my-user-script.txt:text/x-shellscript \
   my-cloudconfig.txt

$ ls -l combined-userdata.txt 
-rw-r--r-- 1 smoser smoser 1782 2010-07-01 16:08 combined-userdata.txt

The combined-userdata.txt is the file you want to paste there.

More info here:

https://help.ubuntu.com/community/CloudInit

Also note, this highly depends on the image you are using. But you say it is really cloud-init based image, so this applies. There are other cloud initiators which are not named cloud-init - then it could be different.