When migrating systems, there are several approaches you can take to migrate the newly conveyed apps:

  • Hard cutover
  • Blue/Green deployments
  • Strangulation

Some of these approaches can be combined while others may only have one option available based on the circumstances.

If an app or piece of infrastructure must be moved, then there is one approach that is not optional, and that is the hard cutover. This is an outage event and is what will finally swing things over to their new home.

How long and number of outages will depend on the other approaches in place and what is being accomplished. The blue/green deployment model strangulation will allow for reduced downtime, but at the cost of additional complexity and maintenance for both companies during the transition.

Does this remind you of anything?

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