Cloud Migration Strategies (7 Rs)

This is an original planning guide. It is not a vendor manual, an official standard, or legal advice. Example addresses use documentation ranges. Review every command before you paste it.

A strategy is one verb for one system

The seven moves are rehost, replatform, repurchase, refactor, relocate, retain, and retire. The selector helps you pick a verb from answers you type. The readiness check is a questionnaire. Neither tool moves a system, and neither tool logs into a platform.

One system gets one verb. A programme that lists every server is not this hour. If two verbs seem true, you have not finished the sentence about what must stay the same.

Retain and retire are successful answers. Not every system should move. Retire needs an owner and a date. Retain needs a reason that is not fear. The cost guide prices a move. It does not force one.

The virtualisation companion on the system desk is useful when the system is a guest you already run. This page does not pick a hypervisor for you, and it does not start a cutover.

One system, one verb, a reason the next person can repeat

Name the system and what it does in one sentence. Answer the selector honestly. Record the verb and the reason. If the tool's suggestion disagrees with the reason, the reason wins and you write why.

Run the readiness questions for that one system. A low score means the move waits. It does not mean you start anyway. Data you may move, the owner, and the rollback of the current system are the three lines that must exist before any later cutover ticket.

Rehost is a copy of the same shape. Replatform changes a part, such as a database service, and the database desk owns that part. Refactor is an application change with its own project. Repurchase is a product decision. Relocate is a site move. Do not mix the verbs in one sentence.

Nothing is migrated in this window. The proof is the paragraph. A cutover plan with a clock belongs to a later ticket that names the maintenance hour.

# Migration note. One system. One verb.
# Rehost, replatform, repurchase, refactor, relocate, retain, retire.
# Retain and retire are allowed answers.
# This hour does not cut over.
# A readiness score does not start a move by itself.

A change you can finish

The later change is a lab copy or a written retire date, not a production cutover.

Rollback of a decision is choosing a different verb before anything moves. Rollback of a cutover is a plan you do not need yet because you did not cut over.

Name one system and its job.
Pick one verb and write the reason.
Answer the readiness questions for that system.
If the score is low, the move waits.
Write data, owner, and what stays running today.
Price the idea with the cost guide only if the verb spends money.
Leave the cutover unscheduled.

Mistakes that outlive the command

the 7 Rs fails in the same few ways. Each one looks finished on the day you type it. The list is here so the ticket can forbid them before the window, not so you can recognise them in an incident review.

Seven verbs for one system.
A cutover in the decision hour.
Moving a system you do not administer.
A customer extract as the test copy.
Retire with no owner and no date.
Retain written only as 'maybe later'.
Ignoring a low readiness score.
Refactor disguised as a weekend rehost.
A database change with no database owner.
A clock time before the verb is agreed.

Decisions to write down before the window

One decision for the 7 Rs: One system is named. One verb is chosen. The reason is a sentence. Readiness was answered. A low score stops the move. The owner is named. Today's system keeps running. No cutover is scheduled. Data to move is described without copying it. The cost guide is involved only if money changes. The infrastructure file is later, if a file is even needed. And a second person can say the verb.

The hour you stop

Write the account, the project or subscription, the region, and the clock time before you change anything for the 7 Rs. If this account is serving people and you do not have a way back, this hour is a plan. A plan you can read tomorrow is a success. A change you cannot undo is not.

Use a lab account, a lab project, or a lab subscription you administer. You do not point a CLI, a pipeline, or a browser tool at an account you do not run. The tools on this site run in the browser. They draft text. They do not log in, and they do not scan.

prompt-for-this is a reminder that a secret is missing. It is not an access key, a token, a password, or a kubeconfig you save. The real secret stays in the password store or the platform's secret store. If a file, a log, a ticket, or a pipeline still contains a live secret, stop and rotate it. Then delete the copy.

One change. A network, a virtual machine, a policy, and a pipeline do not share a window. If two things move and the outcome is wrong, you will not know which one did it. The rollback is the previous file, the previous plan, or the resource you can delete because it was only a lab.

A second person reads the scope aloud: which account, which region, which name. If they cannot find it in the ticket, the ticket is not ready. Silence is not agreement.

Documentation addresses stay in the note. 192.0.2.0/24, 198.51.100.0/24, 203.0.113.0/24, and 2001:db8::/32 are not prefixes you type into a production network. example.com is not your zone. A generated file that opens 0.0.0.0/0 is a file you edit before it is applied. A source you can name is the rule you keep.

Do not apply a draft you have not read. A cost estimate, a policy, a manifest, and a Terraform plan are reading material. Apply, a resize of a live machine, and a delete of a bucket are later decisions with their own proof. Read the names. Then decide.

Keep the previous file. A generator draft is not the previous file. The previous file is what you put back if the new one is wrong. You practised the path back, including the serial console or a second admin, before you changed a network or a lockout setting.

If a step fails twice, stop. The failure is the result. Adding a command from a forum beside a half-applied stack produces an account nobody can explain. Rebuild the lab from the copy you kept.

When the checks pass, the next account waits until someone else can repeat the proof from the notes. the 7 Rs is done for this window when the proof is written, not when a CLI printed a success line.

This page is a planning guide. It is not a vendor manual, not an official standard, not legal advice, and not an audit opinion. If an auditor must see the decision, they see the ticket and the evidence, not this paragraph.

Hand the finished note to the neighbouring guide that owns the next step, and leave this account alone until that guide has its own window.

Migration checks before anyone schedules a cutover

Confirm this before you call the change done: The system name is in the ticket. The verb is one of the seven. The reason matches the verb. Readiness is recorded. No data was copied in this window. No account you do not run was opened. Retire has a date, or retire was not chosen. The current system is still the one serving people. A second person repeats the verb. The cutover line is blank. A database move names the database owner, or there is no database move. The note has no secret and no customer extract. The hostname in the prompt matches the hostname in the ticket for the 7 Rs. The result line includes the time and the person, not only the command. You can point at the rollback value without searching a chat history. And done is a sentence a second person can repeat: the proof for the 7 Rs happened, and the next host is not started early. If one of those fails, stop.

Tools for this guide

These tools run in the browser on this site. They do not log into your machines.

Guides in this cluster

These supporting pages belong to this pillar.

Companion: System: VMware vs Hyper-V vs Proxmox.