Hello folks, I am trying to run the user_data while provisioning the instance, but it doesn’t run anything. The format i am using is

user_data = """
#!/bin/bash
set -eux
sudo aws s3 cp s3://<bucket-name>/<script>.sh /tmp/
"""

Instances = aws.ec2.Instance(
                instance_name,
                ami=ami,
                instance_type=size,
                subnet_id=subnets[1],
                user_data_base64=user_data,
                security_groups=[securitygroup]
            )

If anyone can help to review!

You seem to be passing a simple UTF string in to the base64 version of the parameter?

I tried to use

user_data

parameter as well, but it’s the same thing

And the AMI you're using has bash installed at /bin?

Yes it does have bash preinstalled into the image.

i'm with tenwit, you need to base64 encoded your

user_data

string

Yes i logged into the instance and check but no data available.

You mean http://169.254.169.254/latest/user-data was empty?

No when i do curl to http://169.254.169.254/latest/user-data, it shows the userdata as of the userdata format. but doesn’t run anything.

Hmmm.. as far as I know, there's nothing extra you need for user-data to be run. Can you run /bin/bash?

Well, i tried to search the contents using

find

but seems to be nowhere.

Search what contents?

contents of what i am installing through userdata

No afaik it's magic, and always accessible.. you can access it via curl, that's what happens on startup.

Ah interesting,

I'd try using no shebang, or use /bin/sh. Have you tried running

/bin/bash

from the command line?

No well i am finding the script which is being copied from s3,

user_data = """
#!/bin/bash
set -eux
sudo aws s3 cp s3://<bucket-name>/<script>.sh /tmp/
"""

it’s appearing nowhere.

But you did the

curl

from the instance, right?

Also in this example, it should create

index.html

however i am seeing it using curl metadata but can’t see

index.htmml

being created anywhere.

user_data = """
#!/bin/bash
echo "Hello, World!" > index.html
nohup python -m SimpleHTTPServer 80 &
"""

And one possibility is that

/bin/bash

is failing to run.

Yes, i am able to invoke it from the instance. I checked that earlier.

Ok that's good to know.

Everything looks fine when i run the same script from within in instance, it just doesn’t work with userdata script.

Have you had a look in /var/log/cloud-init.log?

Sure, checking in.

I had the same problem when using the Ubuntu AMI. When you write

user_data

like this:

user_data = """
...
"""

it leaves a leading new line which for some reason doesn't work with Ubuntu (at least 20.04). It works with Amazon Linux, though. I had to remove the empty new line by writing the

user_data

like:

user_data = """\
...
"""

(note the trailing

\

backslash).

@proud-art-41399 That seems interesting, I should try that way.