AWS DMS stands for Amazon Web Services Database Migration Service. It is a fully managed database migration service that helps you migrate databases to AWS quickly and securely. AWS DMS supports both homogeneous migrations, where the source and target databases are of the same engine (e.g., Oracle to Oracle), and heterogeneous migrations, where the source and target databases are of different engines (e.g., Microsoft SQL Server to Amazon Aurora).
Key features of AWS DMS include:
1. Data Replication: AWS DMS can continuously replicate data changes from the source database to the target database, ensuring that the target remains up to date with changes made in the source.
2. Schema Conversion: For heterogeneous migrations, AWS DMS can help convert schema and data types from the source to the target database to ensure compatibility.
3. Minimized Downtime: It allows you to migrate data with minimal downtime by performing an initial data load and then continually synchronizing changes.
4. Database Cloning: You can use DMS to create a clone of your production database for testing and development purposes.
5. Change Data Capture: AWS DMS can capture changes from popular database engines, such as Oracle, SQL Server, MySQL, PostgreSQL, and more, in real-time.
6. Data Filtering and Transformation: You can configure data filtering and transformation rules to control what data gets migrated and how it's transformed during the migration process.
7. Security and Encryption: AWS DMS provides encryption options to ensure the security of your data during migration.
8. Integration with AWS Services: AWS DMS can be integrated with other AWS services, such as AWS Schema Conversion Tool (SCT), AWS Database Assessment Tool (DAT), and AWS Database Query Tool (DQT), to facilitate the migration process.
Overall, AWS DMS is a versatile tool for simplifying and automating database migrations to AWS, making it easier for organizations to move their databases to the cloud while minimizing disruptions to their applications.
Deployment using AWS CDK
To create an AWS Cloud Development Kit (CDK) stack for AWS Database Migration Service (DMS) in Python, you'll need to define the necessary resources, such as replication instances, endpoints, and migration tasks. Below is a basic example of how to create a DMS stack using AWS CDK. Note that you'll need to have the AWS CDK and AWS CLI configured on your system and also install the necessary CDK modules.
from aws_cdk import core
from aws_cdk import aws_dms as dms
from aws_cdk import aws_secretsmanager as secrets_manager
class DMSStack(core.Stack):
def init(self, scope: core.Construct, id: str, **kwargs) -> None:
super().__init__(scope, id, **kwargs)
# Create a secret to store credentials for the source and target databases
source_secret = secrets_manager.Secret(
self, "SourceDatabaseSecret",
description="Secret for source database connection",
generate_secret_string=secrets_manager.SecretStringGenerator(
secret_string_template={"username": "source_username"},
generate_string_key="password",
password_length=12,
exclude_characters='"@/',
),
)
target_secret = secrets_manager.Secret(
self, "TargetDatabaseSecret",
description="Secret for target database connection",
generate_secret_string=secrets_manager.SecretStringGenerator(
secret_string_template={"username": "target_username"},
generate_string_key="password",
password_length=12,
exclude_characters='"@/',
),
)
# Define a replication instance
replication_instance = dms.CfnReplicationInstance(
self, "ReplicationInstance",
replication_instance_class="dms.r5.large",
allocated_storage=100,
)
# Define source and target endpoints
source_endpoint = dms.CfnEndpoint(
self, "SourceEndpoint",
endpoint_identifier="source-endpoint",
endpoint_type="source",
engine_name="mysql",
username=source_secret.secret_value_from_json("username").to_string(),
password=source_secret.secret_value_from_json("password").to_string(),
server_name="source-database-server",
port=3306,
database_name="source_database",
)
target_endpoint = dms.CfnEndpoint(
self, "TargetEndpoint",
endpoint_identifier="target-endpoint",
endpoint_type="target",
engine_name="aurora",
username=target_secret.secret_value_from_json("username").to_string(),
password=target_secret.secret_value_from_json("password").to_string(),
server_name="target-database-cluster",
port=3306,
database_name="target_database",
)
# Create a migration task
migration_task = dms.CfnReplicationTask(
self, "MigrationTask",
migration_task_identifier="my-migration-task",
migration_type="full-load",
source_endpoint_arn=source_endpoint.attr_endpoint_arn,
target_endpoint_arn=target_endpoint.attr_endpoint_arn,
table_mappings="...custom table mapping...",
)
app = core.App()
DMSStack(app, "DMSStack")
app.synth()
In this code, we create a CDK stack that includes:
1. Secrets for storing database credentials.
2. A replication instance for DMS.
3. Source and target endpoints for the source and target databases.
4. A migration task that specifies the type of migration (full-load) and the endpoints to use.
You'll need to customize this code by providing the actual database connection details and table mappings in the migration task. Additionally, you may need to install the required CDK modules and configure AWS CDK on your system before deploying the stack.
