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CLD-C0001 · Cost & FinOps

Cloud Cost Optimization Guide

Estimate one workload before you launch it, name the owner, and stop the lab when the ticket ends.

Updated 25 October 2026 · Pillar guide

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 bill is a list of names you chose

Cost work on this desk is an estimate you can read before a resource exists. The estimator drafts a monthly figure from sizes you type. The rightsizing calculator drafts a smaller size from utilisation you type. Neither tool logs into an account, and neither tool changes a live machine. You still decide.

Start with one workload. Name the owner, the environment, and the hour it should stop. A lab without an owner becomes a line item nobody recognises. A tag you invent after the invoice arrives is a label, not a control.

A commitment is a different hour. Reserved capacity and a savings plan are promises. This page stops at the estimate and one idle resource you can explain. The commitment waits until the same workload has run long enough to measure.

A recommendation is not a resize. If the calculator says a machine looks large, you write that down. You do not resize a machine that is serving people in this window. The instance guide owns the size you pick next.

One estimate, one owner, one stop time

Type the size you think you need into the estimator. Use a lab size, not the largest size on the menu. Record the figure, the assumptions, and the date. If you cannot say what the figure includes, the estimate is not done.

If you already have a utilisation number you are allowed to use, type it into the rightsizing calculator. The suggestion goes in the ticket beside the current size. Agree or disagree in a sentence. Do not click a resize from this page.

Pick one idle resource you administer, or write that the lab has none yet. Idle means nobody can name the workload. The action is a stop or a delete of that lab resource, after a second person agrees it is unused. A production name is not idle because it was quiet for an afternoon.

Write the tag keys you will require: owner, environment, and purpose. A resource without those three is a resource you do not launch. The database cost companion is a neighbouring desk. This page does not price a database you have not designed.

# Cost note. Nothing here logs into an account.
# One workload. One owner. One stop time.
# A calculator suggestion is not a resize.
# A commitment is a later ticket.
# prompt-for-this is not a billing account id you paste into git.

A change you can finish

The change in this window is the written estimate and, if you found a true lab leftover, stopping that one resource. A fleet cleanup is a programme, not this hour.

Rollback for a stopped lab machine is starting it again. Rollback for a deleted disk does not exist unless you already had a copy. Do not delete storage to save money in the same hour you are still learning the bill.

  1. Name the workload, the owner, and the environment.
  2. Run the estimator on a lab size and save the figure.
  3. If you have utilisation, record the rightsizing suggestion.
  4. Agree or disagree in one sentence.
  5. Write the stop time for the lab.
  6. Stop one confirmed idle lab resource, or write that there is none.
  7. Leave commitments and live resizes for their own tickets.

Mistakes that outlive the command

cloud cost 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.

Decisions to write down before the window

Decision 1 for cloud cost. The workload in the estimate is the one in the ticket. Write that decision in the ticket before you change the host. The proof is the smallest command or screen that confirms it, recorded with the hostname and the time. If the host disagrees, the ticket changes. A second change does not go on top of a failed check. The rollback is the previous value you wrote down, not a reboot that hides which line mattered.

Decision 2 for cloud cost. The owner and the environment are written. Write that decision in the ticket before you change the host. The proof is the smallest command or screen that confirms it, recorded with the hostname and the time. If the host disagrees, the ticket changes. A second change does not go on top of a failed check. The rollback is the previous value you wrote down, not a reboot that hides which line mattered.

Decision 3 for cloud cost. The size is a lab size. Write that decision in the ticket before you change the host. The proof is the smallest command or screen that confirms it, recorded with the hostname and the time. If the host disagrees, the ticket changes. A second change does not go on top of a failed check. The rollback is the previous value you wrote down, not a reboot that hides which line mattered.

Decision 4 for cloud cost. The rightsizing line is a suggestion, or it is blank because you have no utilisation yet. Write that decision in the ticket before you change the host. The proof is the smallest command or screen that confirms it, recorded with the hostname and the time. If the host disagrees, the ticket changes. A second change does not go on top of a failed check. The rollback is the previous value you wrote down, not a reboot that hides which line mattered.

Decision 5 for cloud cost. No live machine was resized. Write that decision in the ticket before you change the host. The proof is the smallest command or screen that confirms it, recorded with the hostname and the time. If the host disagrees, the ticket changes. A second change does not go on top of a failed check. The rollback is the previous value you wrote down, not a reboot that hides which line mattered.

Decision 6 for cloud cost. No commitment was purchased. Write that decision in the ticket before you change the host. The proof is the smallest command or screen that confirms it, recorded with the hostname and the time. If the host disagrees, the ticket changes. A second change does not go on top of a failed check. The rollback is the previous value you wrote down, not a reboot that hides which line mattered.

Decision 7 for cloud cost. The lab has a stop time. Write that decision in the ticket before you change the host. The proof is the smallest command or screen that confirms it, recorded with the hostname and the time. If the host disagrees, the ticket changes. A second change does not go on top of a failed check. The rollback is the previous value you wrote down, not a reboot that hides which line mattered.

Decision 8 for cloud cost. Idle meant a lab leftover a second person recognised. Write that decision in the ticket before you change the host. The proof is the smallest command or screen that confirms it, recorded with the hostname and the time. If the host disagrees, the ticket changes. A second change does not go on top of a failed check. The rollback is the previous value you wrote down, not a reboot that hides which line mattered.

Decision 9 for cloud cost. Storage was not deleted to save money. Write that decision in the ticket before you change the host. The proof is the smallest command or screen that confirms it, recorded with the hostname and the time. If the host disagrees, the ticket changes. A second change does not go on top of a failed check. The rollback is the previous value you wrote down, not a reboot that hides which line mattered.

Decision 10 for cloud cost. No secret is in the note. Write that decision in the ticket before you change the host. The proof is the smallest command or screen that confirms it, recorded with the hostname and the time. If the host disagrees, the ticket changes. A second change does not go on top of a failed check. The rollback is the previous value you wrote down, not a reboot that hides which line mattered.

Decision 11 for cloud cost. The instance guide owns the next size. Write that decision in the ticket before you change the host. The proof is the smallest command or screen that confirms it, recorded with the hostname and the time. If the host disagrees, the ticket changes. A second change does not go on top of a failed check. The rollback is the previous value you wrote down, not a reboot that hides which line mattered.

Decision 12 for cloud cost. One workload is this window. Write that decision in the ticket before you change the host. The proof is the smallest command or screen that confirms it, recorded with the hostname and the time. If the host disagrees, the ticket changes. A second change does not go on top of a failed check. The rollback is the previous value you wrote down, not a reboot that hides which line mattered.

The hour you stop

Write the account, the project or subscription, the region, and the clock time before you change anything for cloud cost. 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. cloud cost 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.

Cost checks before another resource is launched

Check 1 in Cost checks before another resource is launched. The estimate figure and the date are in the ticket. Record the device name, the result, and the time on the same line. If the result does not match this check, stop and fix the ticket before you add another change. The rollback for this check is the previous value you wrote down, not a reboot. A reboot hides whether the check was the one that mattered. When the check passes, move to the next one. When it fails, the incident is this check.

Check 2 in Cost checks before another resource is launched. The assumptions are sentences, not only numbers. Record the device name, the result, and the time on the same line. If the result does not match this check, stop and fix the ticket before you add another change. The rollback for this check is the previous value you wrote down, not a reboot. A reboot hides whether the check was the one that mattered. When the check passes, move to the next one. When it fails, the incident is this check.

Check 3 in Cost checks before another resource is launched. The owner tag is decided. Record the device name, the result, and the time on the same line. If the result does not match this check, stop and fix the ticket before you add another change. The rollback for this check is the previous value you wrote down, not a reboot. A reboot hides whether the check was the one that mattered. When the check passes, move to the next one. When it fails, the incident is this check.

Check 4 in Cost checks before another resource is launched. The stop time is decided. Record the device name, the result, and the time on the same line. If the result does not match this check, stop and fix the ticket before you add another change. The rollback for this check is the previous value you wrote down, not a reboot. A reboot hides whether the check was the one that mattered. When the check passes, move to the next one. When it fails, the incident is this check.

Check 5 in Cost checks before another resource is launched. A live resize did not happen. Record the device name, the result, and the time on the same line. If the result does not match this check, stop and fix the ticket before you add another change. The rollback for this check is the previous value you wrote down, not a reboot. A reboot hides whether the check was the one that mattered. When the check passes, move to the next one. When it fails, the incident is this check.

Check 6 in Cost checks before another resource is launched. A commitment did not happen. Record the device name, the result, and the time on the same line. If the result does not match this check, stop and fix the ticket before you add another change. The rollback for this check is the previous value you wrote down, not a reboot. A reboot hides whether the check was the one that mattered. When the check passes, move to the next one. When it fails, the incident is this check.

Check 7 in Cost checks before another resource is launched. A second person can point at the workload. Record the device name, the result, and the time on the same line. If the result does not match this check, stop and fix the ticket before you add another change. The rollback for this check is the previous value you wrote down, not a reboot. A reboot hides whether the check was the one that mattered. When the check passes, move to the next one. When it fails, the incident is this check.

Check 8 in Cost checks before another resource is launched. The lab account is the account you administer. Record the device name, the result, and the time on the same line. If the result does not match this check, stop and fix the ticket before you add another change. The rollback for this check is the previous value you wrote down, not a reboot. A reboot hides whether the check was the one that mattered. When the check passes, move to the next one. When it fails, the incident is this check.

Check 9 in Cost checks before another resource is launched. No billing export was fetched from an account you do not run. Record the device name, the result, and the time on the same line. If the result does not match this check, stop and fix the ticket before you add another change. The rollback for this check is the previous value you wrote down, not a reboot. A reboot hides whether the check was the one that mattered. When the check passes, move to the next one. When it fails, the incident is this check.

Check 10 in Cost checks before another resource is launched. The next size belongs to the instance guide. Record the device name, the result, and the time on the same line. If the result does not match this check, stop and fix the ticket before you add another change. The rollback for this check is the previous value you wrote down, not a reboot. A reboot hides whether the check was the one that mattered. When the check passes, move to the next one. When it fails, the incident is this check.

Check 11 in Cost checks before another resource is launched. GPU or other large labs are named as expensive on purpose. Record the device name, the result, and the time on the same line. If the result does not match this check, stop and fix the ticket before you add another change. The rollback for this check is the previous value you wrote down, not a reboot. A reboot hides whether the check was the one that mattered. When the check passes, move to the next one. When it fails, the incident is this check.

Check 12 in Cost checks before another resource is launched. The note can be repeated without opening the console. Record the device name, the result, and the time on the same line. If the result does not match this check, stop and fix the ticket before you add another change. The rollback for this check is the previous value you wrote down, not a reboot. A reboot hides whether the check was the one that mattered. When the check passes, move to the next one. When it fails, the incident is this check.

Check 13 in Cost checks before another resource is launched. The hostname in the prompt matches the hostname in the ticket for cloud cost. Record the device name, the result, and the time on the same line. If the result does not match this check, stop and fix the ticket before you add another change. The rollback for this check is the previous value you wrote down, not a reboot. A reboot hides whether the check was the one that mattered. When the check passes, move to the next one. When it fails, the incident is this check.

Check 14 in Cost checks before another resource is launched. The result line includes the time and the person, not only the command. Record the device name, the result, and the time on the same line. If the result does not match this check, stop and fix the ticket before you add another change. The rollback for this check is the previous value you wrote down, not a reboot. A reboot hides whether the check was the one that mattered. When the check passes, move to the next one. When it fails, the incident is this check.

Check 15 in Cost checks before another resource is launched. You can point at the rollback value without searching a chat history. Record the device name, the result, and the time on the same line. If the result does not match this check, stop and fix the ticket before you add another change. The rollback for this check is the previous value you wrote down, not a reboot. A reboot hides whether the check was the one that mattered. When the check passes, move to the next one. When it fails, the incident is this check.

Check 16 in Cost checks before another resource is launched. Done is a sentence a second person can repeat: the proof for cloud cost happened, and the next host is not started early. Record the device name, the result, and the time on the same line. If the result does not match this check, stop and fix the ticket before you add another change. The rollback for this check is the previous value you wrote down, not a reboot. A reboot hides whether the check was the one that mattered. When the check passes, move to the next one. When it fails, the incident is this check.

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. A published page is linked. The others are named until they are published.

The content plan also names a companion in another desk: DBA: Managed Database Cost Comparison.