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Lift and Shift - cloud migration strategy

During discussion on different cloud projects I observed that people are using “Lift and Shift” terminology with multiple meanings. This can create confusion between different parties, especially when technical team from each team understand a different thing.

What is Lift and Shift?
Lift and Shift is a migration strategy that is based on the concept of replication 1 to 1 of the environment that exist on-premises inside cloud (Microsoft Azure). This involves the migration of all computation, storage and other services without replacing them with specific Azure services.

What is not Lift and Shift?
When you have a File Server system on the current infrastructure. Lift and Shift in this case shall not include replacing it with Azure Files. Involves just taking the File Servers instances from on-premises and putting them inside Azure VMs.

Another good example is when you migrate a web farm. If you decide to do just a Lift and Shift, than you should just spin Azure VMs where you would use Apache or IIS to host your web endpoints. In this case migrating to App Services and Web Apps is not anymore Lift and Shift.

I’m doing something wrong if I migrate to specific Azure Services?
No, there is nothing wrong in it. Migrating to App Services for example when you host a web site might be a good choice but this such a migration is not a Lift and Shift migration anymore. Just be careful how you define the migration and how you call it.

Why Lift and Shift is important?
In comparison with other migration strategy, Lift and Shift doesn’t replace current services with new ones. This means that in most of the cases the migration will be fast and the level of success confident it is high.
In general, when you use Lift and Shift, the current application SLAs are not affected.

What I don’t get?
From running cost perspective, doing just a Lift and Shift will not reduce costs or optimize consumption. The same thing is from NFRs and SLAs.

Think about Lift and Shift just the 1st step of a migration plan. Once you have your system running inside Azure, you can start identify components and layers of the system that can be replaced by native Azure Services like Azure Files, App Services, Azure SQL.
I call this kind of migration – baby steps. In this way, you can control the risks and reduce the impact to your system. The risk of a fail is reduce drastically.


Conclusion
Don’t forget about terminology. All parties in a discussion shall understand the same thing when you say “Lift and Shift” – one to one migration. 

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