Tech mahindra
Tech mahindra

Complex and Large Scale Database Migration to AWS

Posted by: Ganesh Babu On September 04, 2019 05:45 PM facebook linked in twitter

While Tech Mahindra has extensive experience with migrating thousands of applications to AWS cloud for our global customer base, we would like to take a deep dive about one particular customer engagement where we have migrated large scale legacy complex databases which holds mission critical data and also accessed by multiple applications across different business segments.

Business Requirement

The customer wanted to prepare an enterprise ready AWS cloud platform which will help the business to migrate the workloads to AWS cloud. They also needed us to assess and migrate the business applications (legacy and 3rd party vendor apps) off of data center situated at locations that are vulnerable to tropical and sub-tropical cyclones.

Migration Complexity

• Cross platform Database Migration from IBM AIX to RHEL

• Huge size of the databases 30 TB (Production), 30 TB ( Standby), 30 TB ( DR)

• Inter dependencies among different businesses which have mission critical data.

• On-Premise applications and databases dependencies from different Data Centers

• Building Multiple Standby & DR Databases – AWS on EC2

Tech Mahindra Solution Approach

The first step was to get people, processes and tools to plan, execute and support the workload migrations. Tech Mahindra’s proprietary cloud migration framework (MAC) helped define clear phase and deliverables to ensure seamless migration.

Migration of various environments Development, UAT and Production were into different sprints. The assessment phase comprised of end-to-end analysis of all applications/workloads and producing a comprehensive cloud migration plan including all dependencies. Assessment passport prepared for every application was the key to move into the next phase of migration.

This ensured that business was involved in the migration journey and the TO-BE architecture validated and verified. The passport, application assessment report, encompass all components of the existing and to-be architecture. To-be architecture for the application incorporates all major tenets of the AWS Well Architected Framework to provide highly reliable and secure application. The cutover date is agreed and planned after finalizing on the AWS migration approach.

AWS cloud migration process ends with validation of the completed migration by users to ensure the workload performs as expected. Automation being the key ask from the customer, build and rebuild of infrastructure and applications was through AWS CloudFormation. One of the major highlight was implementing real time data replication across different regions/accounts for DR Solution. The engagement has thus far witnessed AWS migration of about 85 + applications with 120 TB of data with lowest possible downtime during cutover. The engagement has shown how adopting a phase-driven migration strategy helps streamline any kind of migration be it a 3 tier web application or complex backend jobs

Tech Mahindra has also implemented and successfully tested multi region Cloud HA/DR solution to meet RTO/RPO objectives. Enabled the organization to build and accelerate the cloud deployments through agility. Leveraged AWS capabilities for just-in-time provisioning and scale the workloads accordingly. Provisioned highly available, scalable, robust IT landscape to ensure business continuity.

Database Migration Approach

The generic re-host migration methodology will not help fulfilling the end objectives mainly due to huge interdependencies between applications and databases. We strategically followed a big-bang approach as to migrate 75% of the live business to AWS cloud in a single cut-over with 2 day(s) weekend downtime.

Multiple database migration strategies were applied Followed. Considering the complexity and size of the databases, we have used “Incremental Cross-Platform Transportable Tablespaces” for large databases. For few other databases, we have used EXPDP/IMPDP to migrate 5TB old partitioned data in advance and 1TB during the actual cutover.

Value Delivered to Customer

• Migrated enterprise business applications ranging from high complex to medium criticality

• Migrated a 12TB database which holds most of the critical data for enterprise business with lowest possible downtime for the Production cut-over. Total size of databases across all environments exceeds 120+ TB

• Implemented DR solution to real-time data replication across the different accounts/regions using Oracle Data Guard and Log Shipping. Deployed immediate coverage for backup and faster business recovery in case of disaster

In summary, Tech Mahindra was able to help the customer to close the datacentre successfully which was situated at locations that are vulnerable to tropical and sub-tropical cyclones post migrating the most critical energy trading applications as well as the large and complex databases to AWS cloud.

About Author

Ganesh Babu – Senior Cloud Architect & Application Architect, AWS Practice, Tech Mahindra

Ganesh Babu has more than 15+ years of IT experience. He is also an AWS Certified Solution Architect. Part of Tech Mahindra AWS Practice, he has successfully managed and delivered large scale cloud migration engagements for various customers in Healthcare, Energy & Utilities and Media verticals. He also comes up with strong experience in modernizing legacy application using cloud native capabilities.

Tags: Connected Platforms & Solutions, Connected World
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