Migrating Databases to the Cloud

You can migrate your on-premises Oracle Database to an Oracle Cloud Infrastructure Database service database using a number of different methods that use several different tools. The method that applies to a given migration scenario depends on several factors, including the version, character set, and platform endian format of the source and target databases.


Oracle now offers the Zero Downtime Migration service, a quick and easy way to move on-premises Oracle Databases and Oracle Cloud Infrastructure Classic databases to Oracle Cloud Infrastructure. You can migrate databases to the following types of Oracle Cloud Infrastructure systems: Exadata, Exadata Cloud@Customer, bare metal, and virtual machine.

Zero Downtime Migration leverages Oracle Active Data Guard to create a standby instance of your database in an Oracle Cloud Infrastructure system. You switch over only when you are ready, and your source database remains available as a standby. Use the Zero Downtime Migration service to migrate databases individually or at the fleet level. See Move to Oracle Cloud Using Zero Downtime Migration for more information.

Choosing a Migration Method

Not all migration methods apply to all migration scenarios. Many of the migration methods apply only if specific characteristics of the source and destination databases match or are compatible. Moreover, additional factors can affect which method you choose for your migration from among the methods that are technically applicable to your migration scenario.

Some of the characteristics and factors to consider when choosing a migration method are:

  • On-premises database version
  • Database service database version
  • On-premises host operating system and version
  • On-premises database character set
  • Quantity of data, including indexes
  • Data types used in the on-premises database
  • Storage for data staging
  • Acceptable length of system outage
  • Network bandwidth

To determine which migration methods are applicable to your migration scenario, gather the following information.

  1. Database version of your on-premises database:

    • Oracle Database 12c Release 2 version
    • Oracle Database 12c Release 1 version or higher
    • Oracle Database 12c Release 1 version lower than
    • Oracle Database 11g Release 2 version or higher
    • Oracle Database 11g Release 2 version lower than
  2. For on-premises Oracle Database 12c Release 2 and Oracle Database 12c Release 1 databases, the architecture of the database:

    • Multitenant container database (CDB)
    • Non-CDB
  3. Endian format (byte ordering) of your on-premises database’s host platform

    Some platforms are little endian and others are big endian. Query V$TRANSPORTABLE_PLATFORM to identify the endian format, and to determine whether cross-platform tablespace transport is supported.

    The Oracle Cloud Infrastructure Database uses the Linux platform, which is little endian.

  4. Database character set of your on-premises database and the Oracle Cloud Infrastructure Database database.

    Some migration methods require that the source and target databases use compatible database character sets.

  5. Database version of the Oracle Cloud Infrastructure Database database you are migrating to:

    • Oracle Database 12c Release 2
    • Oracle Database 12c Release 1
    • Oracle Database 11g Release 2

    Oracle Database 12c Release 2 and Oracle Database 12c Release 1 databases created on the Database service use CDB architecture. Databases created using the Enterprise Edition software edition are single-tenant, and databases created using the High Performance or Extreme Performance software editions are multitenant.

After gathering this information, use the “source” and “destination” database versions as your guide to see which migration methods apply to your migration scenario:

Migration Connectivity Options

You have several connectivity options when migrating your on-premises databases to the Oracle Cloud Infrastructure. The options are listed below in order of preference.

  1. FastConnect: Provides a secure connection between your existing network and your virtual cloud network (VCN) over a private physical network instead of the internet. For more information, see FastConnect.
  2. Site-to-Site VPN: Provides a secure connection between a dynamic routing gateway (DRG) and customer-premise equipment (CPE), consisting of multiple IPSec tunnels. The IPSec connection is one of the components forming a Site-to-Site VPN between a VCN and your on-premises network. For more information, see Site-to-Site VPN.
  3. Internet gateway: Provides a path for network traffic between your VCN and the internet. For more information, see Internet Gateway.

Migration Methods