Stop 13 · Cloud Migration & Multi-CloudTopics · 1/8

Cloud Migration Strategies (The 6 Rs)

In short

A company with 200 applications can't move them all the same way. Some move as they are, some get rebuilt, and some should simply be switched off. The 6 Rs give each one a label.

A common framework for migration approaches — Rehost (lift-and-shift), Replatform, Repurchase, Refactor, Retire, and Retain — matching the right strategy to each workload rather than treating migration as one-size-fits-all.

The blob character sticks coloured stickers on furniture in a living room before a move.

Think of it like this

Sorting the house before shifting

Before a family shifts cities, someone walks room to room with stickers. The sofa goes as it is. The fridge gets a new stabiliser. The old TV is sold and a new one bought there. The broken chair goes to the kabadiwala. Dadi's cupboard stays back.

Watch it happen

The 6 Rs, from least to most effort

Retire

Retain

Rehost

Replatform

Repurchase

Refactor

1/7Six labels, roughly ordered by how much work each one takes. Every application gets exactly one.

The big ideas

What you need to know

One label per app

You decide the R for each workload, not for the whole company. A big migration usually mixes all six.

Retire first

Assessment often finds apps nobody uses. Turning them off saves money and shrinks the migration list.

Speed vs benefit

Rehost is quick but carries old problems along. Refactor takes months but gets you autoscaling and lower running costs.

Sometimes seven

AWS now lists a seventh R, Relocate, for moving whole VMware setups without changing them. The idea stays the same.

Save yourself the pain

Common mistakes

Oops

Choosing "refactor everything" because cloud-native sounds modern.

Do this instead

Refactor only what will really benefit. Rehosting the rest first gets you out of the data centre sooner.

Oops

Migrating every app, including ones nobody uses.

Do this instead

Check usage first. Retiring dead apps is the fastest and cheapest win you'll get.

Your mission

Label a pretend company

~25 min

Quick check

A college runs its own email server and decides to switch to a hosted email service. Which R is this?

Go deeper

1Memorize the 6 Rs and give one example scenario for each.
2Classify a hypothetical legacy application into the most appropriate migration strategy.
3Learn why 'refactor everything' is rarely the fastest or most cost-effective starting approach.