Finding all Amazon AWS Instances That Do Not Have a Certain Tag

Question

I\'m trying to use the Amazon AWS Command Line Tools to find all instances that do not have a specified tag.

Finding all instances WITH a tag is simple enough, e.g.<

Answer 1

I use this python3 / boto script for very large inverse tag filtering operations:

import boto3
from botocore.config import Config

# Attempts
config = Config(
  retries = dict(
    max_attempts = 3
  )
)

# Tag(s)
my_tags = [
  {
    "Key": "backup",
    "Value": "true"
  }
]

# Owner ID Filter
owner_id = 'SOME_OWNER_ID'

# Connection
ec2 = boto3.client("ec2", config=config)

# Instances
def tag_instances():
  # All Reservations [instances] (tagged or untagged)
  all_reservations = ec2.describe_instances(Filters = [{'Name': 'owner-id', 'Values':[owner_id]}])

  # Append each InstanceId in all_reservations to all_instances
  all_instances = []
  for all_reservation in all_reservations['Reservations']:
    for all_instance in all_reservation['Instances']:
      all_instances.append(all_instance['InstanceId'])

  # Append each InstanceId with backup:true or backup:false to tagged_instances
  tagged_reservations = ec2.describe_instances(Filters = [{'Name': 'owner-id', 'Values':[owner_id]},{'Name': 'tag:backup', 'Values':['true','false']}])
  tagged_instances = []
  for tagged_reservation in tagged_reservations['Reservations']:
    for tagged_instance in tagged_reservation['Instances']:
      tagged_instances.append(tagged_instance['InstanceId'])

  # Append each InstanceId in all_instances and not in tagged_instances to untagged_instances
  untagged_instances = [all_instance for all_instance in all_instances if all_instance not in tagged_instances]

  # Print untagged InstanceId
  print("untagged_instanceids:",untagged_instances)