Migrate from Oracle to Amazon DocumentDB using AWS DMS
Created by Sashikanta Pattanayak (AWS) and Munesh Siddappa (AWS)
Environment: PoC or pilot | Source: Databases: Relational | Target: Amazon DocumentDB |
R Type: Re-architect | Workload: Oracle | Technologies: Migration; Databases |
AWS services: Amazon DocumentDB |
Summary
This pattern provides guidance for migrating an Oracle database to an Amazon DocumentDB (with MongoDB compatibility) database by using AWS Database Migration Service (AWS DMS). This approach can be applied to an on-premises Oracle source database as well as an Amazon Relational Database Service (Amazon RDS) for Oracle DB instance. This pattern uses an Amazon RDS Oracle DB source instance as an example.
Amazon DocumentDB (with MongoDB compatibility) is a fully managed, MongoDB-compatible document database service that makes it easy to store, query, and index JSON data.
The use case for this pattern is one-to-one replication of an Oracle database table to an Amazon DocumentDB collection. The pattern uses AWS DMS replication tasks to read the table structure of the Oracle database, create the corresponding collection in Amazon DocumentDB, and perform a full load migration. You can view and query your data in Amazon DocumentDB, the same as you would in MongoDB.
Prerequisites and limitations
Prerequisites
An active AWS account
Familiarity with using Oracle databases
Familiarity with using Amazon DocumentDB
For the Oracle user,
SELECT ANY TABLEprivilegeFor the Amazon DocumentDB use, the privilege required to dump data
Limitations
The following limitations apply when using Amazon DocumentDB as a target for AWS DMS:
In Amazon DocumentDB, collection names can't contain the dollar symbol ($). In addition, database names can't contain any Unicode characters.
AWS DMS doesn't support merging of multiple source tables into a single Amazon DocumentDB collection.
When AWS DMS processes changes from a source table that doesn't have a primary key, any large binary object (LOB) columns in that table are ignored.
If the Change table option is enabled and AWS DMS encounters a source column named "_id", that column appears as "__id" (two underscores) in the change table.
If you choose Oracle as a source endpoint, the Oracle source must have full supplemental logging enabled. Otherwise, if there are columns at the source that weren't changed, the data is loaded into Amazon DocumentDB as null values.
Product versions
Amazon RDS for Oracle version 11.2.0.3 or later
AWS DMS version 3.1.3 or later (for the latest version information, see Using Amazon DocumentDB as a Target for AWS DMS in the AWS DMS documentation)
Architecture
Source technology stack
Amazon RDS for Oracle DB instance
Target technology stack
Amazon DocumentDB
Source and target architecture
Tools
AWS DMS – AWS Database Migration Service (AWS DMS) is a web service that you can use to migrate data from a source data store to a target data store. The AWS DMS User Guide specifies the Oracle source database versions and editions that are supported for use with AWS DMS. For additional information relevant to this pattern, see Using Amazon DocumentDB as a Target for AWS DMS.
Amazon EC2 – Amazon Elastic Compute Cloud (Amazon EC2) provides scalable computing capacity in the AWS cloud. Your Amazon DocumentDB cluster should be running in your default virtual private cloud (VPC). To interact with your Amazon DocumentDB cluster, you must launch an EC2 instance into your default VPC, in the same AWS Region where you created your Amazon DocumentDB cluster. For details, refer to Launch an Amazon EC2 instance in the Amazon DocumentDB documentation.
Epics
| Task | Description | Skills required |
|---|---|---|
Validate the source and target database versions and engines. | AWS Admin | |
Choose the proper instance type (capacity, storage features, network features). | AWS Admin | |
Identify network/host access security requirements for the source and target databases. | AWS Admin | |
Create an outbound security group to the source and target databases. | AWS Admin | |
Create and configure an EC2 instance for Amazon DocumentDB. | AWS Admin |
| Task | Description | Skills required |
|---|---|---|
Create a VPC and subnets. | AWS Admin | |
Create security groups and network access control lists (ACLs). | AWS Admin | |
Configure and start the source Amazon RDS for Oracle instance. | AWS Admin | |
Configure and start the Amazon DocumentDB instance. | AWS Admin |
| Task | Description | Skills required |
|---|---|---|
Verify that the Oracle database can be connected using the connection details. | AWS Admin | |
Verify that the Oracle user has the SELECT ANY TABLE privilege. | AWS Admin |
| Task | Description | Skills required |
|---|---|---|
Create the Amazon DocumentDB cluster by choosing the proper instance class and number of instances. | AWS Admin |
| Task | Description | Skills required |
|---|---|---|
Configure the EC2 instance. | To interact with your Amazon DocumentDB cluster, you must launch an EC2 instance into your default VPC, in the same AWS Region where you created your Amazon DocumentDB cluster. Configure the AWS Region, VPCs, Availability Zones, and subnets for the EC2 instance. | AWS Admin |
Configure the key pair. | A public/private key pair allows you to connect securely to the EC2 instance after it launches. | AWS Admin |
Set the bastion host CIDR ranges (optional). | Set the CIDR IP range that is allowed for external Secure Shell (SSH) access to the bastion host instances. | AWS Admin |
| Task | Description | Skills required |
|---|---|---|
Create an AWS DMS replication instance. | AWS Admin | |
Create source and target endpoints. | AWS Admin | |
Create AWS DMS replication tasks for a full load. | AWS Admin |
| Task | Description | Skills required |
|---|---|---|
Connect to the Amazon DocumentDB cluster through the EC2 instance. | AWS Admin | |
Connect to the cluster using the mongo shell. | For instructions, see the Amazon DocumentDB links in the References and Help section. | AWS Admin |
Verify the results of the migration. | AWS Admin |
Related resources
