Related: DBMS, RDS, Amazon Aurora,
No downtime migration service.
Consists of
- Source Endpoint
- EC2 Replication instance
- Target Endpoint
Replication instance performs the migration between Source and Destination endpoints which store connection information for source and target databases
Has 3 types of jobs.
- Full Job - one-off migration of all data
- Full Job + CDC (Change data capture) - migrates existing data + ongoing changes (full load migration)
- CDC only - migrates only data changes (when you used other tool migrate full DB)
Also goes along with SCT
Schema Conversion Tool (SCT)
Related: AWS Snow Family
Helps to convert/change DB schema. Mostly used when migrating to another DB engine.
SCT is not used when migrating between DB's of the same type like MySQL to RDS MySQL.
Works with:
- OLTP DB Types (MySQL, MSSQL, Oracle)
- OLAP (Teradata, Oracle, Vertica, Greenplum..
Used in cases like: - e.g. On-Premises MSSQL → RDS MySQL
- e.g. On-premises ORACLE → Aurora
If DB is multi-TB it maybe impractical to transfer data over network. AWS Snow Family is a solution, DMS can utilise snowball …
- Step 1 : Use SCT to extract data locally and move to a snowball device
- Step 2: Ship the device back to AWS. They load onto an S3 bucket.
- Step 3: DMS migrates from S3 into the target store
- Step 4: Change Data Capture (CDC) can capture changes, and via S3 intermediary they are also written to the target database