What are the most challenging data migration projects you have worked on?

I did migration of below on-premises databases to AWS cloud services, almost no or very less downtime. - On-Prem MySQL -> AWS RDS Aurora MySQL - On-Prem Cassandra -> AWS ec2 Cassandra -> AWS Keyspace - On-Prem Mongo -> AWS ec2 Mongo -->(Yet to do) - AWS RDS MySQL -> AWS RDS Aurora PostGreSQL. Below high level task & overall considerations : - Assessment and Planning: - Schema Migration - Data Migration - Data Consistency and Verification - Testing and Validation - Post-migration Optimization - Backup and Disaster Recovery - Security Configuration - Monitoring and Optimization - Compliance and Best Practices

One of the biggest challenges I faced during a legacy CRM migration was managing the customizations and addressing gaps in knowledge. Customizations (and there were several) were deeply ingrained in the legacy system, which posed a dual challenge — preserving their functionality or deciding whether to retain, modify, or replace them in the new environment. Simultaneously, addressing gaps in knowledge, especially when dealing with outdated documented customizations and processes, resulted in several challenges. It's crucial to implement a comprehensive knowledge transfer strategy and maintain documentation of your current tech stack. This way, when these types of migration projects are needed, you are set up for success.

Legacy system migration can present several challenges, including: Compatibility Issues: Legacy systems often use outdated technology, programming languages, or platforms that may not easily integrate with modern systems or software. Business Process Alignment: Legacy systems might have unique workflows or functionalities that are not directly supported in newer systems. Aligning these legacy processes with modern ones requires careful planning and analysis. Rollback can be tricky also.

I worked in a migration from a legacy system because it was not prepare to the Y2K. The Legacy System was in Cobol and we pass it to MSSQL Server 7. We passed from Cobol to VB6 with SQL SERVER. I was hard but we made it possible. 1997-1999

Lift and shift or simply re-hosting is the easiest way to bring your data into the cloud (IaaS). If you're going to migrate to some PaaS offering there can be some limitations in functionality and detailed assessment should be performed before migration. Moreover some PoC migrations should be performed before dealing with Prod data.

Cross-platform or heterogeneous migration in most cases contain multiple issues with data type conversions, especially when there are a lot of user-defined data types in your database. There are many tools which can help performing such migration but I've never met a tool which will perform pretty complicated cross-platform migration without any issues or data loss. So be careful and double check everything.

Migration Of Oracle 19c Database From AIX To Linux Using Transportable Tablespace. factors to consider when choosing a migration method are: Source and target database versions Source platform and operating system Source database character set Quantity of data, including indexes Methods available for data transportation Database features and data types used Storage for data staging Acceptable length of system outage Network bandwidth.

If you're looking for project that can highlight all your data quality issues, data lake, and data warehouse projects will do just that. Often, these challenges begin with a simple question: how to create a reliable source of truth? These types of projects require a strategic approach to overcome the challenges posed by disparate data sources, data silos, and evolving data schemas. Having actively participated in these types of projects, I can't stress enough the significance of addressing data quality issues preemptively – it lays the groundwork for a successful delivery. Perhaps more importantly, it aligns your organization with a holistic approach that encompasses data governance, integration protocols, and ongoing monitoring mechanisms.

Pretty easy to setup for small to medium data amount but really complicated for huge amounts of data. Reliable network connection with high bandwidth is corner stone for real-time migrations especially when we talk about hybrid cloud environments.

With any migration project, take the opportunity to look for enhancements; parity should not be the sole focus. Instead of merely replicating existing functionalities, consider how the migration can serve as a catalyst for improvement. This means assessing your current systems, workflows, and user experiences—to identify areas for optimization. By shifting the focus from mere replication to strategic improvement, your migration project can become a transformative journey for organizations.