How to use Lambda to automatically download files uploaded to S3 to EC2 (Windows)

Question

I want to use Lambda to automatically transfer files uploaded to S3 to EC2 (Windows).
To do this, I have configured the following:
Set s3:ObjectCreated:* as a trigger to invoke Lambda (Python).
Start windows server 2022 and set IAM role to AdministratorAccess.
Set IAM role of Lambda to AdministratorAccess.

These were implemented.
However, when I execute the following in Python 3.7 and store the file in S3, it starts without error, but the file is not transferred to EC2.

Please give me some advice.

```
import logging
import boto3

LOGGER = logging.getLogger()
LOGGER.setLevel(logging.INFO)
ec2 = boto3.client('ec2')
ssm = boto3.client('ssm')
INSTANCE_ID = 'i-***'

def lambda_handler(event, context):
    try:
		#Get EC2 State
        ec2_resp = ec2.describe_instances(InstanceIds=[INSTANCE_ID]),
        ec2_state = ec2_resp['Reservations'][0]['Instances'][0]['State']['Name']
        if not ec2_state == "running":
            LOGGER.info('No EC2 is running')
            return "END"
		# RunPowerShellScript
        command = r"aws s3 sync s3://***/ C:/Users/Administrator/Desktop/***/"
        ssm.send_command(
            InstanceIds=[INSTANCE_ID],
            DocumentName="AWS-RunPowerShellScript",
            Parameters={
                "commands":[command],
                "executionTimeout":["3600"]
            },
        )
    
    except Exception as error:
        LOGGER.error(error)
        raise error
```

Uri · Answer

Why are you using Lambda in this case? I would send the S3 notification to SQS and have a process polling the queue on the EC2 instance. When it receives a new message, it download the file and process it.

Edward_S · Answer

I implemented similar solution in the past using S3 --> EventBridge --> Lambda function which invoked a SSM command

Example:
```
    bucket_name = event['bucket_name']
    s3_object = event['object_key']
    instance_id = event['instance_id']
    destination_path = event['destination']

command_string = f"Copy-S3Object -BucketName {bucket_name} -Key {s3_object} -LocalFile {destination_path}\{s3_object}"
    cmd_id = ssm_client.send_command(
         InstanceIds=[instance_id],
         DocumentName="AWS-RunPowerShellScript",
         Parameters={"commands": [command_string]},
         CloudWatchOutputConfig={"CloudWatchOutputEnabled": True}
     )
```

You will also need to verify that the EC2 instance has the proper IAM permissions assigned to access the S3 bucket and objects as well as the proper permissions for SSM management.

Lasantha Sanjeewa Silva · Answer

Try Mountpoint for Amazon S3 - https://aws.amazon.com/blogs/aws/mountpoint-for-amazon-s3-generally-available-and-ready-for-production-workloads/

How to use Lambda to automatically download files uploaded to S3 to EC2 (Windows)

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