Lift & Shift
In a ‘Lift-and-Shift’, the emphasis is on migration speed (and cost). Systems are moved from their current location (e.g. a hosting provider or internal data centre) and are moved to a cloud provider with little or no change to the architecture or configuration. Because time is not spent rethinking the architecture, the time required to make a move is typically very quick. In Lift-and-Shift the cloud is treated as an on-demand, pay-per-use hosting environment. Please see the below image on how this typical process would look.
Lift & Refit
A popular approach to cloud migrations is the ‘Lift-and-Refit’. Here, the applications are re-deployed onto a cloud with a moderate number of changes that allow them to take advantage of many of the popular cloud capabilities such as:
- Auto-healing & recovery
- Design for failure
- Infrastructure as Code
- Self Documenting Infrastructure
- Data backup & restore
- Auto-scaling (up/down) based on current or predicted usage
- Orchestrated provisioning best practices
- Monitoring & alerting
In a Lift-and-Refit, there are typically no code changes made to the system. The refitting occurs outside of the code by repackaging the software and giving the cloud environment enough information about the software to automate common operational activities, leading to reduced maintenance.
In a Cloud Modernization effort, the application or infrastructure or something both is redesigned from the ground-up with the assumption that it will be deployed in a cloud environment. Reengineering applications for a native cloud environment provide the greatest degree of flexibility however are also the most costly in the short term. Over time, the new application may provide enough benefits related to reduced administrative costs, reduced computing charges or other cost recovery vehicles to warrant an over-haul.