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Planning the migration
In a migration, a system is transitioned from its initial state to a target state.
The Migration encompasses all steps necessary to achieve this transition.
Important preconditions are that the initial state as well as the target state
are known and can described in a suitable way. Information about the initial
state can generally be gathered from:
The internal IT department
Specialists for migration support
Using a questionnaire supplied by the Cloud provider
It is important that all relevant facts, configurations, settings, quantities, etc.
be taken into account. Experience has shown that only in the rarest of cases,
even with good documentation, is the “current system” described in
sufficient detail.
A description of the target state can be obtained from:
The internal IT department in cooperation with specialists from the
Cloud provider.
Specialists for migration support.
The previous experience of the Cloud provider. In this case, however,
the description should be cross‐checked for completeness and
understandability by the planning team.
Once the target and initial states have been sufficiently documented, the
next step is to plan the migration. In the process, the following must be
taken into account:
All technical and organisational steps before the migration. The goal
should be to work out all prerequisites for the start of the migration.
All the steps during the migration. For this, it is recommendable to
identify several milestones at marked or critical points of the
migration. These steps generally lead to a "GO" decision.
All steps that are necessary after a "GO" decision until normal
operations can be resumed.
All steps that are necessary after a "NO‐GO" decision in order to
restore the initial state.
