A lambda function that will copy EC2 tags to all related Volumes and Network Interfaces. A full writeup can be found on my site http://mlapida.com/thoughts/tagging-and-snapshotting-with-lambda

EC2-Tag-Assets-Lambda.py

import boto3

def lambda_handler(event, context):
    is_test = context.function_name == 'test'  # this value is injected by SAM local
    instances = boto3.resource('ec2').instances.all()

    copyable_tag_keys = ["Team", "Billing", "BillingTag", "Env", "Project"]

    for instance in instances:
        copyable_tags = [t for t in instance.tags
                         if t["Key"] in copyable_tag_keys] if instance.tags else []
        if not copyable_tags:
            continue

        # Tag the EBS Volumes
        print(f"{instance.instance_id}: {instance.tags}")
        for vol in instance.volumes.all():
            print(f"{vol.attachments[0]['Device']}: {copyable_tags}")
            if not is_test:
                vol.create_tags(Tags=copyable_tags)

        # Tag the Elastic Network Interfaces
        for eni in instance.network_interfaces:
            print(f"eth{str(eni.attachment['DeviceIndex'])}: {copyable_tags}")
            if not is_test:
                eni.create_tags(Tags=copyable_tags)

lambda-role-iam-policy.json

{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Effect": "Allow",
            "Action": [
                "logs:CreateLogGroup",
                "logs:CreateLogStream",
                "logs:PutLogEvents"
            ],
            "Resource": "arn:aws:logs:*:*:*"
        },
        {
            "Effect": "Allow",
            "Action": [
                "ec2:DescribeInstances",
                "ec2:DescribeVolumes",
                "ec2:CreateTags"
            ],
            "Resource": "*"
        }
    ]
}