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Query EC2 Instances

Now that you have an introduction to querying your AWS account with cnquery, let's dive deeper and explore EC2 instances.

We'll continue working in the cnquery shell, which makes running individual queries easy. If it's not already open, enter cnquery shell aws in your terminal. To learn about accessing your AWS account with cnquery, read Query AWS Infrastructure.

EC2 resources​

cnquery provides answers to any question about your EC2 instances. To discover all the resources and fields you can query, read aws.ec2. You can also use the help command in the shell:

help aws.ec2

In this tutorial we'll explore just a few of the possibilities.

Run simple queries on EC2 instances​

This query gathers all your EC2 instances:

aws.ec2.instances

It returns each instance's ARN and current state:

aws.ec2.instances: [
  0: aws.ec2.instance arn="arn:aws:ec2:us-east-1:921877552404:instance/i-06e2eaa19a4fa883e" state="stopped"
  1: aws.ec2.instance arn="arn:aws:ec2:us-east-1:921877552404:instance/i-0facc86d89af823af" state="stopped"
  2: aws.ec2.instance arn="arn:aws:ec2:us-east-1:921877552404:instance/i-0b24443c8d18fdbab" state="running"
  3: aws.ec2.instance arn="arn:aws:ec2:us-west-1:921877552404:instance/i-020eed3b1e4965d8d" state="running"
  4: aws.ec2.instance arn="arn:aws:ec2:us-west-1:921877552404:instance/i-08f2ba2424027454a" state="running"
]

Specify fields to include in results​

You can request specific data by including the field names. For example, this query collects the ARN and any assigned tags for each instance:

aws.ec2.instances { arn tags }

It returns a list with only the information you asked for:

aws.ec2.instances: [
  0: {
    tags: {
      Name: "k8s-operator01"
      owner: "suki@lunalectric.com"
    }
    arn: "arn:aws:ec2:us-east-1:921877552404:instance/i-06e2eaa19a4fa883e"
  }
  1: {
    tags: {
      Name: "vm-with-ebs-iam-role"
    }
    arn: "arn:aws:ec2:us-east-1:921877552404:instance/i-0facc86d89af823af"
  }
  2: {
    tags: {
      Name: "amazonlinux2-for-ebs-volume-scan"
      owner: "kembe@lunalectric.com"
    }
    arn: "arn:aws:ec2:us-east-1:921877552404:instance/i-0b24443c8d18fdbab"
  }
  3: {
    tags: {}
    arn: "arn:aws:ec2:us-west-1:921877552404:instance/i-020eed3b1e4965d8d"
  }
  4: {
    tags: {
      Name: "amos-linux"
    }
    arn: "arn:aws:ec2:us-west-1:921877552404:instance/i-08f2ba2424027454a"
  }
]

Filter results​

You can filter results based on any fields. Specify the criteria using the where function and standard boolean operators.

For example, this query requests only EC2 instances that do not have an owner tag:

aws.ec2.instances.where(tags['owner'] == null)

It lists each instance's ARN and status:

aws.ec2.instances.where: [
  0: aws.ec2.instance arn="arn:aws:ec2:us-east-1:921877552404:instance/i-06e2eaa19a4fa883e" state="stopped"
  1: aws.ec2.instance arn="arn:aws:ec2:us-east-1:921877552404:instance/i-0facc86d89af823af" state="stopped"
  2: aws.ec2.instance arn="arn:aws:ec2:us-west-1:921877552404:instance/i-020eed3b1e4965d8d" state="running"
  3: aws.ec2.instance arn="arn:aws:ec2:us-west-1:921877552404:instance/i-08f2ba2424027454a" state="running"
]

This finds large (more expensive) EC2 instances:

aws.ec2.instances.where(instanceType == /^.*.large$/) { arn instanceType }

It returns a list of all instances that have an instanceType with large in the name.

This similar query finds T-type instances (such as T2, or T4g):

aws.ec2.instances.where(instanceType == /^[t].*/) { instanceType }

Learn more about querying EC2 instances​

  • To learn more about how the MQL query language works, read Write Effective MQL.
  • For a list of all the AWS resources and fields you can query, read aws.ec2.

Next step​

To discover more of cnquery's AWS capabilities, query your EKS clusters.