RDS Sufficient Backup Retention Period

Risk Level: Medium (should be achieved)

Rule ID: RDS-003

Ensure that your Amazon RDS database instances have set a minimum backup retention period in order to achieve compliance requirements. Trend Cloud One™ – Conformity recommends a minimum (default) retention period of 7 (seven) days but you can adjust the minimumRetentionPeriod parameter value to narrow or extend the default retention period (Amazon RDS allows a maximum retention period of 35 days).

This rule can help you with the following compliance standards:

NIST4

For further details on compliance standards supported by Conformity, see here.

This rule can help you work with the AWS Well-Architected Framework.

This rule resolution is part of the Conformity Security & Compliance tool for AWS.

Reliability

Having a minimum retention period set for your database instances will enforce your backup strategy to follow best practices as specified in the compliance regulations. Retaining point-in-time database snapshots for a longer period of time will allow you to handle more efficiently your data restoration process in the event of failure.

Note: This guide will use 7 days (recommended) as the threshold for the minimum backup retention period. However, you can adjust anytime the number of days to suit your requirements.

Audit

To determine if your Amazon RDS database instances have a sufficient backup retention period configured for automated backups, perform the following actions:

Using AWS Console

01 Sign in to the AWS Management Console.

02 Navigate to Amazon RDS console at https://console.aws.amazon.com/rds/.

03 In the navigation panel, under Amazon RDS, choose Databases.

04 Click on the name of the Amazon RDS database instance that you want to examine. To identify RDS database instances, check the resource role available in the Role column (i.e. Instance).

05 Select the Maintenance & backups tab and check the Automated backups configuration attribute value. If the attribute value is set to Disabled, automated backups are not enabled for the selected database instance, therefore the Audit process ends here. If the Automated backups attribute value is set to Enabled, check the retention period (in days) included in the configuration status, i.e. Enabled (<retention-period-in-days>), where <retention-period-in-days> represents the backup retention period configured for the selected instance. If the <retention-period-in-days> is less than 7 (seven) days, the backup configuration available for the selected Amazon RDS database instance is not compliant.

06 Repeat steps no. 4 and 5 for each Amazon RDS database instance available within the current AWS region.

07 Change the AWS cloud region from the navigation bar and repeat the Audit process for other regions.

Using AWS CLI

01 Run describe-db-instances command (OSX/Linux/UNIX) with custom query filters to list the names of the Amazon RDS database instances provisioned in the selected AWS region:

aws rds describe-db-instances
  --region us-east-1
  --output table
  --query 'DBInstances[*].DBInstanceIdentifier'

02 The command output should return a table with the requested database instance names:

--------------------------------
|     DescribeDBInstances      |
+------------------------------+
|  cc-project5-mysql-database  |
|  cc-main-postgres-database   |
+------------------------------+

03 Run describe-db-instances command (OSX/Linux/UNIX) using the name of the Amazon RDS database instance that you want to examine as the identifier parameter and custom query filters to determine the retention period configured for the automated backups, for the selected database instance:

aws rds describe-db-instances
  --region us-east-1
  --db-instance-identifier cc-project5-mysql-database
  --query 'DBInstances[*].BackupRetentionPeriod'

04 The command output should return the retention period (number of days) configured for the selected database instance:

[
    2
]

If the describe-db-instances command output returns 0, automated backups are not enabled for the selected Amazon RDS database instance, therefore the Audit process ends here. If the number returned by the describe-db-instances command output is less than 7 (seven days), the backup configuration available for the selected Amazon RDS database instance is not compliant.

05 Repeat steps no. 3 and 4 for each Amazon RDS database instance available in the selected AWS region.

06 Change the AWS cloud region by updating the --region command parameter value and repeat the Audit process for other regions.

Remediation / Resolution

To update your Amazon RDS database instance backup configuration in order to extend the backup retention period for compliance, perform the following actions:

Using AWS CloudFormation

01 CloudFormation template (JSON):

{
	"AWSTemplateFormatVersion": "2010-09-09",
	"Description": "Configure Backup Retention Period for Automated Backups",
	"Parameters": {
		"DBInstanceName": {
			"Default": "mysql-database-instance",
			"Description": "RDS database instance name",
			"Type": "String",
			"MinLength": "1",
			"MaxLength": "63",
			"AllowedPattern": "^[0-9a-zA-Z-/]*$",
			"ConstraintDescription": "Must begin with a letter and must not end with a hyphen or contain two consecutive hyphens."
		},
		"DBInstanceClass": {
				"Default": "db.t2.micro",
				"Description": "DB instance class/type",
				"Type": "String",
				"ConstraintDescription": "Must provide a valid DB instance type."
		},
		"DBAllocatedStorage": {
			"Default": "20",
			"Description": "The size of the database (GiB)",
			"Type": "Number",
			"MinValue": "20",
			"MaxValue": "65536",
			"ConstraintDescription": "Must be between 20 and 65536 GiB."
		},
		"DBName": {
			"Default": "mysqldb",
			"Description": "Database name",
			"Type": "String",
			"MinLength": "1",
			"MaxLength": "64",
			"AllowedPattern": "[a-zA-Z][a-zA-Z0-9]*",
			"ConstraintDescription": "Must begin with a letter and contain only alphanumeric characters."
		},
		"DBUsername": {
			"Description": "Master username for database access",
			"Type": "String",
			"MinLength": "1",
			"MaxLength": "16",
			"AllowedPattern": "[a-zA-Z][a-zA-Z0-9]*",
			"ConstraintDescription": "Must begin with a letter and contain only alphanumeric characters."
		},
		"DBPassword": {
			"NoEcho": "true",
			"Description": "Password for database access",
			"Type": "String",
			"MinLength": "8",
			"MaxLength": "41",
			"AllowedPattern": "[a-zA-Z0-9]*",
			"ConstraintDescription": "Must contain only alphanumeric characters."
		}
	},
	"Resources": {
		"RDSInstance": {
			"Type": "AWS::RDS::DBInstance",
			"Properties": {
				"DBInstanceIdentifier": {
					"Ref": "DBInstanceName"
				},
				"DBName": {
					"Ref": "DBName"
				},
				"MasterUsername": {
					"Ref": "DBUsername"
				},
				"MasterUserPassword": {
					"Ref": "DBPassword"
				},
				"DBInstanceClass": {
					"Ref": "DBInstanceClass"
				},
				"AllocatedStorage": {
					"Ref": "DBAllocatedStorage"
				},
				"Engine": "MySQL",
				"EngineVersion": "5.7.36",
				"BackupRetentionPeriod": 7
			}
		}
	}
}

02 CloudFormation template (YAML):

AWSTemplateFormatVersion: '2010-09-09'
	Description: Configure Backup Retention Period for Automated Backups
	Parameters:
		DBInstanceName:
		Default: mysql-database-instance
		Description: RDS database instance name
		Type: String
		MinLength: '1'
		MaxLength: '63'
		AllowedPattern: ^[0-9a-zA-Z-/]*$
		ConstraintDescription: Must begin with a letter and must not end with a hyphen
			or contain two consecutive hyphens.
		DBInstanceClass:
		Default: db.t2.micro
		Description: DB instance class/type
		Type: String
		ConstraintDescription: Must provide a valid DB instance type.
		DBAllocatedStorage:
		Default: '20'
		Description: The size of the database (GiB)
		Type: Number
		MinValue: '20'
		MaxValue: '65536'
		ConstraintDescription: Must be between 20 and 65536 GiB.
		DBName:
		Default: mysqldb
		Description: Database name
		Type: String
		MinLength: '1'
		MaxLength: '64'
		AllowedPattern: '[a-zA-Z][a-zA-Z0-9]*'
		ConstraintDescription: Must begin with a letter and contain only alphanumeric
			characters.
		DBUsername:
		Description: Master username for database access
		Type: String
		MinLength: '1'
		MaxLength: '16'
		AllowedPattern: '[a-zA-Z][a-zA-Z0-9]*'
		ConstraintDescription: Must begin with a letter and contain only alphanumeric
			characters.
		DBPassword:
		NoEcho: 'true'
		Description: Password for database access
		Type: String
		MinLength: '8'
		MaxLength: '41'
		AllowedPattern: '[a-zA-Z0-9]*'
		ConstraintDescription: Must contain only alphanumeric characters.
	Resources:
		RDSInstance:
		Type: AWS::RDS::DBInstance
		Properties:
			DBInstanceIdentifier: !Ref 'DBInstanceName'
			DBName: !Ref 'DBName'
			MasterUsername: !Ref 'DBUsername'
			MasterUserPassword: !Ref 'DBPassword'
			DBInstanceClass: !Ref 'DBInstanceClass'
			AllocatedStorage: !Ref 'DBAllocatedStorage'
			Engine: MySQL
			EngineVersion: 5.7.36
			BackupRetentionPeriod: 7

Using Terraform

01 Terraform configuration file (.tf):

terraform {
	required_providers {
		aws = {
			source  = "hashicorp/aws"
			version = "~> 3.27"
		}
	}

	required_version = ">= 0.14.9"
}

provider "aws" {
	profile = "default"
	region  = "us-east-1"
}

resource "aws_db_instance" "rds-database-instance" {
	allocated_storage     = 20
	engine                = "mysql"
	engine_version        = "5.7"
	instance_class        = "db.t2.micro"
	name                  = "mysqldb"
	username              = "ccmysqluser01"
	password              = "ccmysqluserpwd"
	parameter_group_name  = "default.mysql5.7"

	# Configure Backup Retention Period for Automated Backups
	backup_retention_period = 7

	apply_immediately = true
}

Using AWS Console

01 Sign in to the AWS Management Console.

02 Navigate to Amazon RDS console at https://console.aws.amazon.com/rds/.

03 In the navigation panel, under Amazon RDS, choose Databases.

04 Select the Amazon RDS database instance that you want to reconfigure and choose Modify.

05 On the Modify DB instance: <instance-name> configuration page, perform the following actions:

In the Additional configuration section, under Backup, choose a number between 7 and 35 from the Backup retention period dropdown list to set the number of days for which database backups (snapshots) are retained.
Choose Continue and review the configuration changes that you want to apply, available in the Summary of modifications section.
In the Scheduling of modifications section, perform one of the following actions based on your workload requirements:
- Select Apply during the next scheduled maintenance window to apply the changes automatically during the next scheduled maintenance window.
- Select Apply immediately to apply the changes right away. With this option any pending modifications will be asynchronously applied as soon as possible, regardless of the maintenance window configured for the selected RDS database instance. Note that any changes available in the pending modifications queue are also applied. If any of the pending modifications require downtime, choosing this option can cause unexpected downtime for your database application.
Choose Modify DB instance to apply the configuration changes.

06 Repeat steps no. 4 and 5 for each Amazon RDS database instance available in the selected AWS region.

07 Change the AWS cloud region from the navigation bar and repeat the Remediation process for other regions.

Using AWS CLI

01 Run modify-db-instance command (OSX/Linux/UNIX) to extend the backup retention period (in days) for automated backups, for the selected Amazon RDS database instance. The following command request example sets the backup retention period to 7 days and makes use of --apply-immediately parameter to apply the configuration changes asynchronously and as soon as possible. Any changes available in the pending modifications queue are also applied with this request. If any of the pending modifications require downtime, choosing this option can cause unexpected downtime for your database application. If you skip adding the --apply-immediately parameter to the command request, Amazon RDS will apply your changes during the next maintenance window:

aws rds modify-db-instance
  --region us-east-1
  --db-instance-identifier cc-project5-mysql-database
  --backup-retention-period 7
  --apply-immediately

02 The command output should return the configuration metadata for the modified database instance:

{
	"DBInstance": {
		"PubliclyAccessible": true,
		"MasterUsername": "ccadmin",
		"MonitoringInterval": 0,
		"LicenseModel": "general-public-license",
		"VpcSecurityGroups": [
			{
				"Status": "active",
				"VpcSecurityGroupId": "sg-0abcd1234abcd1234"
			},
			{
				"Status": "active",
				"VpcSecurityGroupId": "sg-abcd1234"
			}
		],
		"InstanceCreateTime": "2021-05-12T08:00:00.677Z",
		"CopyTagsToSnapshot": true,
		"OptionGroupMemberships": [
			{
				"Status": "in-sync",
				"OptionGroupName": "default:mysql-5-7"
			}
		],
		"PendingModifiedValues": {
			"BackupRetentionPeriod": 7
		},        
		"Engine": "mysql",
		"MultiAZ": false,
		"DBSecurityGroups": [],
		"DBParameterGroups": [
			{
				"DBParameterGroupName": "default.mysql5.7",
				"ParameterApplyStatus": "in-sync"
			}
		],
		"PerformanceInsightsEnabled": true,
		"AutoMinorVersionUpgrade": true,
		"PreferredBackupWindow": "06:02-06:32",
		"DBSubnetGroup": {
			"Subnets": [
				{
					"SubnetStatus": "Active",
					"SubnetIdentifier": "subnet-abcd1234",
					"SubnetOutpost": {},
					"SubnetAvailabilityZone": {
						"Name": "us-east-1d"
					}
				},
				{
					"SubnetStatus": "Active",
					"SubnetIdentifier": "subnet-1234abcd",
					"SubnetOutpost": {},
					"SubnetAvailabilityZone": {
						"Name": "us-east-1e"
					}
				},
				{
					"SubnetStatus": "Active",
					"SubnetIdentifier": "subnet-abcdabcd",
					"SubnetOutpost": {},
					"SubnetAvailabilityZone": {
						"Name": "us-east-1b"
					}
				},
				{
					"SubnetStatus": "Active",
					"SubnetIdentifier": "subnet-12341234",
					"SubnetOutpost": {},
					"SubnetAvailabilityZone": {
						"Name": "us-east-1a"
					}
				},
				{
					"SubnetStatus": "Active",
					"SubnetIdentifier": "subnet-abcd1234",
					"SubnetOutpost": {},
					"SubnetAvailabilityZone": {
						"Name": "us-east-1f"
					}
				},
				{
					"SubnetStatus": "Active",
					"SubnetIdentifier": "subnet-1234abcd",
					"SubnetOutpost": {},
					"SubnetAvailabilityZone": {
						"Name": "us-east-1c"
					}
				}
			],
			"DBSubnetGroupName": "default-vpc-abcdabcd",
			"VpcId": "vpc-abcdabcd",
			"DBSubnetGroupDescription": "Created from the AWS Management Console",
			"SubnetGroupStatus": "Complete"
		},
		"ReadReplicaDBInstanceIdentifiers": [],
		"AllocatedStorage": 70,
		"DBInstanceArn": "arn:aws:rds:us-east-1:123456789012:db:cc-project5-mysql-database",
		"BackupRetentionPeriod": 2,
		"PreferredMaintenanceWindow": "thu:03:27-thu:03:57",
		"Endpoint": {
			"HostedZoneId": "ABCDABCDABCD",
			"Port": 3306,
			"Address": "cc-project5-mysql-database.abcdabcdabcd.us-east-1.rds.amazonaws.com"
		},
		"DBInstanceStatus": "available",
		"IAMDatabaseAuthenticationEnabled": true,
		"EngineVersion": "5.7.30",
		"DeletionProtection": true,
		"AvailabilityZone": "us-east-1a",
		"DomainMemberships": [],
		"StorageType": "gp2",
		"DbiResourceId": "db-ABCDABCDABCDABCDABCDABCDAB",
		"CACertificateIdentifier": "rds-ca-2019",
		"StorageEncrypted": true,
		"AssociatedRoles": [],
		"DBInstanceClass": "db.t3.medium",
		"DbInstancePort": 0,
		"DBInstanceIdentifier": "cc-project5-mysql-database"
	}
}

03 Repeat steps no. 1 and 2 for each Amazon RDS database instance available in the selected AWS region.

04 Change the AWS cloud region by updating the --region command parameter value and repeat the Remediation process for other regions.

References

AWS Command Line Interface (CLI) Documentation
rds
describe-db-instances
modify-db-instance

CloudFormation Documentation
Amazon Relational Database Service resource type reference

Terraform Documentation
AWS Provider

Publication date May 4, 2016

Audit

Using AWS Console

Using AWS CLI

Remediation / Resolution

Using AWS CloudFormation

Using Terraform

Using AWS Console

Using AWS CLI

References

Related RDS rules