Must Know Things about Data Guard In Oracle Cloud Infrastructure

This post, cover things every DBA, Cloud DBA or Apps DBA must know about Data Guard in Oracle Cloud Infrastructure (OCI). If you are new to Oracle Cloud Infrastructure or just started learning it, I would suggest you check my previous post where I have covered core terminologies & basic concepts related to Oracle Cloud Infrastructure (OCI)

Introduction To Data Guard

Oracle Data Guard enables & ensure high availability, data protection, and disaster recovery for your enterprise database.

Oracle Data Guard provides an extensive set of services that create, maintain, manage, and monitor one or more standby databases to enable production Oracle databases to survive disasters (such as natural calamities) and data corruptions.

Oracle Data Guard maintains these standby databases as a cloned version of the production database and regularly apply changes from Primary Database to Standby Database. Then, If the production database becomes unavailable because of a planned or an unplanned outage, Oracle Data Guard can switch any standby database to the production role, minimizing the downtime associated with the outage.

You Can Configure Two Type of Data Guard based on our requirement

Active Data Guard: Active Data Guard enables read-only access to a physical standby database for queries, sorting, reporting, Web-based access, and so on, while continuously applying changes received from the production database.

Normal Data Guard: Normal Data Guard enables you to switch to the Standby Database when your primary database is down due to some outage or natural calamities. In normal Data guard, you can still the open the standby database in read-mode but changes not applied while in read only mode.

Data Guard in Oracle Cloud

We can configure Data Guard in Oracle Cloud in two different Database offerings from Oracle Cloud which is Compute know as OCI and second is Compute-Classic also known as OCI-C. If you want to know more about OCI and OCI-C check our previous post on OCI vs OCI Classic: IaaS from Oracle.

In this post, we will be seeing Data Guard Configurations in Oracle Cloud Infrastructure (OCI), wherein please stay tuned for the part -2 of this blog where I will be going to cover Data Guard in OCI-C

Data Guard in Oracle Cloud Infrastructure (OCI)

To design and implement DR solutions on Oracle Cloud Infrastructure, it’s important to know which Oracle Cloud Infrastructure features and services have built-in capabilities for a reliable, secure, and cost-effective DR.

Regions and Availability Domains: Oracle Cloud Infrastructure is hosted in regions and availability domains. A region is a localized geographic area, and an availability domain is one or more data centers located within a region, to know more about Regions & Availability Domains click here
Compute: Oracle Cloud Infrastructure Compute lets you provision and manage to compute hosts, known as instances You can launch instances as needed to meet your compute and application requirements. to know more about Compute check here
Storage: Oracle Cloud Infrastructure has a wide range of offerings in storage and you can choose any one of them based on your requirements, these are Object Storage service, Storage Gateway, Block Volumes service & File Storage service to more various Storage click here
Networking: Networking Plays a key component while designing DR. Oracle Cloud Infrastructure provides several network-related services and features to meet your application DR requirements, to know about Networking in OCI click here
Database: The Oracle Cloud Infrastructure Database service offers several types of Oracle databases, enabling you to quickly launch a database system that meets your needs & requirements. You have full access to the Database features and operations available with the database wherein Oracle owns and manages the infrastructure, to know more about Database in OCI click here

Common Scenarios of Failure in Oracle Cloud Infrastructure (OCI)

Application Failure: An application can fail because of its own exceptions, changes in underlying resources, and so on. It’s important to include monitoring capability in your DR solution design so that your application failures are detected and alerts are sent.
Network Failure: For DR, consider potential network outage in your cloud environment. For example, if you use an IPSec VPN to connect your on-premises data centers to Oracle Cloud Infrastructure, you could encounter potential network performance or outage issues for this IPSec VPN connection. We recommend setting up multiple IPSec VPN connections or using both FastConnect and IPSec VPN connections so that you have sufficient redundancy for your network connections.
Data Center Impact in Region Failure: An unexpected event could affect an entire data center (availability domain). In your DR solution design, plan for this kind of failure. This potential is one of the reasons that each Oracle Cloud Infrastructure region consists of three availability domains. We recommend deploying your applications across multiple availability domains to accommodate potential issues for a particular data center.
Whole Region Failure (Natural Disaster): Although it would be rare, a natural disaster could cause an entire Oracle Cloud Infrastructure region to be out of service. This scenario could be one of the most severe cases in your DR design. In this scenario, we recommend using multiple Oracle Cloud Infrastructure regions for your DR solution.

DR Deployment Strategies in Oracle Cloud Infrastructure (OCI)

Single Region with Multiple Availability Domains: Depending on the criticality of your applications, you could deploy the applications in a single region. Because each region has multiple availability domains, you can deploy your applications across multiple availability domains to accommodate potential failures in a single availability domain.

Cross Region: For your mission-critical applications, consider a cross-region design for your DR solution. Oracle Cloud Infrastructure provides robust and high-performance backbones between Oracle Cloud Infrastructure regions. You can use remote VCN peering to establish secure and reliable connections between different VCNs across regions.

Things Need to be Taken Care of Before Deploying Data Guard on OCI

Both Primary & Standby DB systems must be in the same compartment, and they must be the same shape, to know more about Compartment click here
The database versions and editions of primary & standby must be identical. As of Nov 2018 Data Guard does not support Standard Edition in OCI & Active Data Guard requires Enterprise Edition – Extreme Performance.) To know more about Databaase offerings in OCI click here
Both Primary & Standby systems must use the same the VCN, and port 1521 must be open, to know more about VCN in OCI check here
As of Nov 2018, Data Guard configuration on the Oracle Cloud Infrastructure is limited to one standby database per primary database.

Note: The standby databases in Oracle Cloud Infrastructure Database are physical standbys & as of Nov 2018 Data Guard supports in Bare Metal

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Now it’s your turn to post your doubts in the comment section and let us know where you are facing challenges in Oracle Cloud Infrastructure

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Comments

Raj Gupta says

December 15, 2018 at 2:20 am

Thanks for sharing the details.
As we must have to place primary and standby in common compartment.. how we can place in vcn if we opted two different regions for primary and standby. VCN is regional resource and subnet is AD based. We must need different CIDR which not overlap with remote peering.

Please share your thoughts.
Once again thank you so much.

Thanks.

- Sabir NOOR MOHAMED says
  
  December 15, 2018 at 8:19 am
  
  Hi Raj Gupta,
  
  As of December 2018 while creating DataGuard in Oracle Cloud Infrastructure from the console it must be in the same compartment, Database is of Both DB systems must be in the same compartment, and they must be the same shape. The database versions and editions must be identical. Data Guard does not support Standard Edition. (Active Data Guard requires Enterprise Edition – Extreme Performance.). Also From the console, it is only supported for Database Created on VM & Bare Metal, it is not applicable for Database created on Exadata DB System
  
  The scenario which you talking about cannot be achieved from OCI Console, however, we can set up cross- region dataguard or between on-premise to cloud data guard yes we have set not overlap
  cidr block & connection will be done via remote peering
  
  Thanks & Regards,
  Rohit(TeamK21)
  
  - Raj Gupta says
    
    December 15, 2018 at 5:44 pm
    
    Thanks for reply.
    I am little confused about what mentioned above. I am trying to say we can’t have same VCN as it will overlap during remote peering. we can achieve DG cross region in OCI but not with same VCN.
    
    Again VCN is regional resource and subnet is AD based.
    
    Please correct me if anything missed.
    
    Thanks
    Raj Gupta

Data Guard In Oracle Cloud Infrastructure (OCI): Things Cloud DBA Must Know