Data migration is the process of transferring data between data storage systems, data formats or computer systems. A data migration project is usually undertaken to replace or upgrade servers or storage equipment, for a website consolidation, to conduct server maintenance or to relocate a data center.
Typically data migration occurs during an upgrade of existing hardware or transfer to a completely new system. Examples include: migration to or from hardware platform; upgrading a database or migrating to new software; or company-mergers when the parallel systems in the two companies need to be merged into one. There are three main options to accomplish data migration:
- Merge the systems from the two companies into a brand new one
- Migrate one of the systems to the other one.
- Leave the systems as they are but create a common view on top of them – a data warehouse.
Factors to consider in a data migration project include how long the migration will take; the amount of downtime required; and the risk to the business from technical compatibility issues, data corruption, application performance issues, and missed data or data loss.
There are three broad categories of data movers:
- Host-based software is best for application-specific migrations such as platform upgrades and for database replication and file copying.
- Array-based software is primarily used to migrate data between like systems.
- Network appliances migrate volumes, files or blocks of data depending on their configuration.
The following best practices should be used to protect data during a migration:
- Understand what data you are migrating, where it lives, what form it’s in and the form it will take at its new destination.
- Extract, transform and deduplicate data before moving it.
- Implement data migration policies so data is moved in an orderly manner.
- Test and validate the migrated data to ensure it is accurate.
- Audit and document the entire data migration process.