1. Home
  2. Knowledge Base
  3. Zero Downtime Migration
  4. Oracle database 12c to 21c online migration using ZDM (Zero Downtime Migration) – Part 2

Oracle database 12c to 21c online migration using ZDM (Zero Downtime Migration) – Part 2

Oracle Zero Downtime Migration (ZDM) is the free-to-use Oracle Maximum Availability Architecture (MAA)-recommended solution to migrate Oracle Databases to the Oracle Cloud Infrastructure.

ZDM provides a number of migration options – Physical offline,Physical online, Logical offline, Logical online.

In a Logical Online migration, users are still connected to a live database while ZDM is executing in the background. Internally ZDM uses Oracle GoldenGate technology to enable the ‘zero-downtime’ migration as well as Oracle Data Pump.

These series of posts provide a step-by-step procedure of how to do an Online Logical Migration of an Oracle Database 12c to Oracle Database 21c.

In this example both the source 12c and target 21c databases are hosted in OCI – but the same procedure can easily be adopted to migrate (and upgrade) an on-premises Oracle database to OCI.

In Part 1, we discussed how to create and configure the ZDM hub.

In the second part of the series, we will create and configure the GoldenGate hub.

From the OCI Console, Marketplace, All Applications menu, enter GoldenGate in the search box.

Select Oracle GoldenGate – Database Migrations.

Select the appropriate compartment and click on Launch Stack.

Note the stack information – Oracle GoldenGate 21.8 Microservices.

Enter a name and description for the GoldenGate hub and click on Next.

A compute node will be provisioned in the stack creation process. Provide the appropriate OCI VCN and subnet information as well as the host name for the compute node. Click on Next.

Select the appropriate Availability Domain and Compute Shape for the compute node which will be provisioned. Provide the name for the GoldenGate deployment and provide the SSH key details for connectivity to the compute node after stack creation.

Click on Next.

Monitor the resource manager job and after the status of the job shows as “SUCCEEDED”, we can also view the resource manager log file.

At the end of the log file we will obtain the IP address information of the newly created compute node which will serve as the GoldenGate hub. The same IP address information can also be obtained via the OCI console from the Compute Instances page.

SSH via putty to the GoldenGate hub compute node as the opc user.

Open the ogg-credentials.json file and make a note of the credential. We will need this at a later stage in the ZDM deployment procedure.

-bash-4.2$ pwd


-bash-4.2$ cat  ogg-credentials.json

{"username": "oggadmin", "credential": "QIJACUH4hLqCq_.o"}

Updated on May 8, 2023

Was this article helpful?

Related Articles

Leave a Comment