# Amazon EC2 example two
<a name="ct-ec2two"></a>

In the following example, an IAM principal running an Amazon EC2 instance creates and mounts a data volume that is encrypted under a KMS key. This action generates multiple CloudTrail log records. For more information on Amazon EBS and encryption, see [Requirements for Amazon EBS encryption](https://docs.aws.amazon.com/ebs/latest/userguide/ebs-encryption-requirements.html#ebs-encryption-instance-permissions).

When the volume is created, Amazon EC2, acting on behalf of the customer, gets an encrypted data key from AWS KMS (`GenerateDataKeyWithoutPlaintext`). Then it creates a grant (`CreateGrant`) that allows it to decrypt the data key. When the volume is mounted, Amazon EC2 calls AWS KMS to decrypt the data key (`Decrypt`).

The `instanceId` of the Amazon EC2 instance, `"i-81e2f56c"`, appears in the `RunInstances` event. The same instance ID qualifies the `granteePrincipal` of the grant that is created (`"111122223333:aws:ec2-infrastructure:i-81e2f56c"`) and the assumed role that is the principal in the `Decrypt` call (`"arn:aws:sts::111122223333:assumed-role/aws:ec2-infrastructure/i-81e2f56c"`). 

The [key ARN](concepts.md#key-id-key-ARN) of the KMS key that protects the data volume, `arn:aws:kms:us-west-2:111122223333:key/1234abcd-12ab-34cd-56ef-1234567890ab`, appears in all three AWS KMS calls (`CreateGrant`, `GenerateDataKeyWithoutPlaintext`, and `Decrypt`).

```
{
  "Records": [
    {
      "eventVersion": "1.02",
      "userIdentity": {
            "type": "IAMUser",
            "principalId": "EX_PRINCIPAL_ID",
            "arn": "arn:aws:iam::111122223333:user/Alice",
            "accountId": "111122223333",
            "accessKeyId": "EXAMPLE_KEY_ID",
            "userName": "Alice"
      },
      "eventTime": "2014-11-05T21:35:27Z",
      "eventSource": "ec2.amazonaws.com",
      "eventName": "RunInstances",
      "awsRegion": "us-west-2",
      "sourceIPAddress": "192.0.2.0",
      "userAgent": "AWS Internal",
      "requestParameters": {
        "instancesSet": {
          "items": [
            {
              "imageId": "ami-b66ed3de",
              "minCount": 1,
              "maxCount": 1
            }
          ]
        },
        "groupSet": {
          "items": [
            {
              "groupId": "sg-98b6e0f2"
            }
          ]
        },
        "instanceType": "m3.medium",
        "blockDeviceMapping": {
          "items": [
            {
              "deviceName": "/dev/xvda",
              "ebs": {
                "volumeSize": 8,
                "deleteOnTermination": true,
                "volumeType": "gp2"
              }
            },
            {
              "deviceName": "/dev/sdb",
              "ebs": {
                "volumeSize": 8,
                "deleteOnTermination": false,
                "volumeType": "gp2",
                "encrypted": true
              }
            }
          ]
        },
        "monitoring": {
          "enabled": false
        },
        "disableApiTermination": false,
        "instanceInitiatedShutdownBehavior": "stop",
        "clientToken": "XdKUT141516171819",
        "ebsOptimized": false
      },
      "responseElements": {
        "reservationId": "r-5ebc9f74",
        "ownerId": "111122223333",
        "groupSet": {
          "items": [
            {
              "groupId": "sg-98b6e0f2",
              "groupName": "launch-wizard-2"
            }
          ]
        },
        "instancesSet": {
          "items": [
            {
              "instanceId": "i-81e2f56c",
              "imageId": "ami-b66ed3de",
              "instanceState": {
                "code": 0,
                "name": "pending"
              },
              "amiLaunchIndex": 0,
              "productCodes": {
                
              },
              "instanceType": "m3.medium",
              "launchTime": 1415223328000,
              "placement": {
                "availabilityZone": "us-east-1a",
                "tenancy": "default"
              },
              "monitoring": {
                "state": "disabled"
              },
              "stateReason": {
                "code": "pending",
                "message": "pending"
              },
              "architecture": "x86_64",
              "rootDeviceType": "ebs",
              "rootDeviceName": "/dev/xvda",
              "blockDeviceMapping": {
                
              },
              "virtualizationType": "hvm",
              "hypervisor": "xen",
              "clientToken": "XdKUT1415223327917",
              "groupSet": {
                "items": [
                  {
                    "groupId": "sg-98b6e0f2",
                    "groupName": "launch-wizard-2"
                  }
                ]
              },
              "networkInterfaceSet": {
                
              },
              "ebsOptimized": false
            }
          ]
        }
      },
      "requestID": "41c4b4f7-8bce-4773-bf0e-5ae3bb5cbce2",
      "eventID": "cd75a605-2fee-4fda-b847-9c3d330ebaae",
      "eventType": "AwsApiCall",
      "recipientAccountId": "111122223333"
    },
    {
      "eventVersion": "1.02",
      "userIdentity": {
            "type": "IAMUser",
            "principalId": "EX_PRINCIPAL_ID",
            "arn": "arn:aws:iam::111122223333:user/Alice",
            "accountId": "111122223333",
            "accessKeyId": "EXAMPLE_KEY_ID",
            "userName": "Alice"
      },
      "eventTime": "2014-11-05T21:35:35Z",
      "eventSource": "kms.amazonaws.com",
      "eventName": "CreateGrant",
      "awsRegion": "us-east-1",
      "sourceIPAddress": "192.0.2.0",
      "userAgent": "AWS Internal",
      "requestParameters": {
        "constraints": {
          "encryptionContextSubset": {
            "aws:ebs:id": "vol-f67bafb2"
          }
        },
        "granteePrincipal": "111122223333:aws:ec2-infrastructure:i-81e2f56c",
        "keyId": "arn:aws:kms:us-west-2:111122223333:key/1234abcd-12ab-34cd-56ef-1234567890ab"
      },
      "responseElements": {
        "grantId": "abcde1237f76e4ba7987489ac329fbfba6ad343d6f7075dbd1ef191f0120514a"
      },
      "requestID": "41c4b4f7-8bce-4773-bf0e-5ae3bb5cbce2",
      "eventID": "c1ad79e3-0d3f-402a-b119-d5c31d7c6a6c",
      "readOnly": false,
      "resources": [
        {
          "ARN": "arn:aws:kms:us-west-2:111122223333:key/1234abcd-12ab-34cd-56ef-1234567890ab",
          "accountId": "111122223333"
        }
      ],
      "eventType": "AwsApiCall",
      "recipientAccountId": "111122223333"
    },
    {
      "eventVersion": "1.02",
      "userIdentity": {
          "type": "IAMUser",
          "principalId": "EX_PRINCIPAL_ID",
          "arn": "arn:aws:iam::111122223333:user/Alice",
          "accountId": "111122223333",
          "accessKeyId": "EXAMPLE_KEY_ID",
          "userName": "Alice"
      },
      "eventTime": "2014-11-05T21:35:32Z",
      "eventSource": "kms.amazonaws.com",
      "eventName": "GenerateDataKeyWithoutPlaintext",
      "awsRegion": "us-east-1",
      "sourceIPAddress": "192.0.2.0",
      "userAgent": "AWS Internal",
      "requestParameters": {
        "encryptionContext": {
          "aws:ebs:id": "vol-f67bafb2"
        },
        "numberOfBytes": 64,
        "keyId": "alias/aws/ebs"
      },
      "responseElements": null,
      "requestID": "create-111122223333-758247346-1415223332",
      "eventID": "ac3cab10-ce93-4953-9d62-0b6e5cba651d",
      "readOnly": true,
      "resources": [
        {
          "ARN": "arn:aws:kms:us-west-2:111122223333:key/1234abcd-12ab-34cd-56ef-1234567890ab",
          "accountId": "111122223333"
        }
      ],
      "eventType": "AwsApiCall",
      "recipientAccountId": "111122223333"
    },
    {
      "eventVersion": "1.02",
      "userIdentity": {
        "type": "AssumedRole",
        "principalId": "111122223333:aws:ec2-infrastructure:i-81e2f56c",
        "arn": "arn:aws:sts::111122223333:assumed-role/aws:ec2-infrastructure/i-81e2f56c",
        "accountId": "111122223333",
        "accessKeyId": "",
        "sessionContext": {
          "attributes": {
            "mfaAuthenticated": "false",
            "creationDate": "2014-11-05T21:35:38Z"
          },
          "sessionIssuer": {
            "type": "Role",
            "principalId": "111122223333:aws:ec2-infrastructure",
            "arn": "arn:aws:iam::111122223333:role/aws:ec2-infrastructure",
            "accountId": "111122223333",
            "userName": "aws:ec2-infrastructure"
          }
        }
      },
      "eventTime": "2014-11-05T21:35:47Z",
      "eventSource": "kms.amazonaws.com",
      "eventName": "Decrypt",
      "awsRegion": "us-east-1",
      "sourceIPAddress": "192.0.2.0",
      "requestParameters": {
        "encryptionContext": {
          "aws:ebs:id": "vol-f67bafb2"
        }
      },
      "responseElements": null,
      "requestID": "b4b27883-6533-11e4-b4d9-751f1761e9e5",
      "eventID": "edb65380-0a3e-4123-bbc8-3d1b7cff49b0",
      "readOnly": true,
      "resources": [
        {
          "ARN": "arn:aws:kms:us-west-2:111122223333:key/1234abcd-12ab-34cd-56ef-1234567890ab",
          "accountId": "111122223333"
        }
      ],
      "eventType": "AwsApiCall",
      "recipientAccountId": "111122223333"
    }
  ]
}
```