This post is part of the “Database Migration to Oracle Cloud Infrastructure blog series", which includes the posts related to database migration. Use these posts as building blocks for various migration approaches.
For more information on Oracle Database and Exadata Cloud Services, review the details at Oracle Cloud Infrastructure - Database
Use the following checklist to help you evaluate and plan for the migration of your databases to Oracle Cloud Infrastructure, based on the unique requirements of your source and target databases.
Work with your database admins, network admins, and system admins as necessary to determine all of the required information for your migration.
- Downtime: Determine from your business what the downtime service level agreements (SLAs) are and how much downtime, if any, the business can accommodate. You can also review Recovery Time Objective (RTO) and Recovery Point Objective (RPO) SLAs to see how much downtime is acceptable according to your disaster recovery (DR) and business continuity (BC) guidelines.
- Database Size: Determine the data volume. Typically, the size of the database is based on two factors: whether the physical or logical migration method is considered, and whether all or part of the data will be migrated to the target database.
- Network Bandwidth: Determine the available network bandwidth between the source and target databases. In addition to available bandwidth, network reliability is also important. Based on the data transfer method, network interruption might require you to restart the data transfer job.
- Cross-Platform Migration: Determine the endianness of the source and target platforms. Oracle Cloud Infrastructure databases are little-endian. If your source database is big-endian, you can either select the logical migration method, which is typically slower, or use Oracle Data Guard or RMAN cross-platform features for the cross-platform migrations.
- Database Character Set: Determine the database character set for the source and target databases. For most migration methods, the target database character set must be a superset of the source database character set. Some methods might need the exact same character set to avoid data loss.
- Data Encryption: Determine whether the source database uses Transparent Data Encryption (TDE). TDE is mandatory for all Oracle Cloud Infrastructure databases. If TDE not used at the source, enable it either at the source or at the target. Be sure to back up and restore the required TDE wallets from the source to the target.
- Database Version, Edition, and Options: Determine the database version, edition, and options for the source and target databases. Based on the migration method, the target and source database version and edition must be compatible. For the Oracle Cloud Infrastructure 12c database target, the multitenant architecture is mandatory, so ensure that the selected migration method can accomplish the migration into the CDB/PDB, as needed.
- Databases Patches: Determine the patch level for the source and target databases. Ensure that the source and target are at the same or compatible Patch Set and Release Upgrade level. Apply any required patches at the source to minimize any discrepancies during or after the migration. Also, as necessary, apply any one-off patches at the target.
- DB Name: Determine the database name used at the source database. For full database restore methods, it is mandatory to create the target database by using the same database name as used at the source database. However, use the DB Unique Name of the target as created by the Oracle Cloud Infrastructure tooling.
- DB Block Size: Determine the database block size used at the source database. For partial restore methods like transportable tablespaces, it might be necessary to adjust the cache size parameters based on the target database.
- DB Time Zone: Determine the database time zone used at the source database. It might be necessary to adjust the database time zone at the target database.
- DB Users, Privileges, and Objects: Determine the database users, privileges, and objects, like DB Links, from the source database that might also need to be created at the target database.
- Sizing: Determine the source database sizing and consider future growth to size the target database. In addition to CPU and Memory, ensure the sizing meets your IOPS and Network Bandwidth requirements.
- Target Database: To ensure the target database will have all the required metadata for OCI tooling to work, create the target database using one of the supported methods like OCI Console, OCI CLI or Terraform OCI provider. This target database will be cleaned to be used as a shell for the migration, as needed.