Outcome
By the end of this lesson, you will be able to name the everyday causes of cloud sprawl and spot the signs of it on a bill.
| Prerequisites | L1, L3 |
| Time | 8 minutes |
1. Concept
Sprawl is what happens when cloud resources pile up faster than anyone tidies them away. It is the cloud version of a garage that slowly fills with things nobody remembers buying.
Sprawl is not caused by careless people. It is caused by how the cloud works.
Cause 1: creating is easy, cleaning up is nobody’s job
Creating a resource takes a minute and solves today’s problem. Deleting it later solves nobody’s problem today, so it waits. Over months, the waiting list grows.
Cause 2: nobody owns it
When a resource has no tag and sits in a shared account, there is no obvious person to ask “do you still need this?” People are reluctant to delete something they did not create, in case it turns out to matter. So it stays.
Cause 3: copies that never die
Teams make copies all the time: a copy of the database for a test, a new environment for a demo, a backup “just in case”. Each was meant to be temporary. Without an end date, temporary becomes permanent.
Cause 4: leftovers
As I.3 L2 showed, deleting a machine can leave its disks, snapshots, addresses and network pieces behind. Each is small, and each keeps billing.
Cause 5: people move on
Engineers change teams, projects end and companies reorganise. The resources stay where they were, and the person who knew what they were for has gone.
The signs on a bill
You can often spot sprawl without any special tools:
- Steady growth with no new product or customers to explain it.
- Costs in regions the company does not use on purpose.
- Accounts or projects with names nobody recognises.
- A large share of cost with no tags.
- Storage and snapshot lines that only ever go up.
What keeps sprawl in check
No single fix exists, but a few habits help a lot: tag every resource with an owner and an environment, give temporary things an end date, switch non-production off when it is not used, and review the biggest untagged and unrecognised costs every month.
2. Worked example
A company reviews one dev account. Here is what it finds, with illustrative monthly costs:
| What it found | Why it was still there | Illustrative monthly cost |
|---|---|---|
| 4 test machines, running all month | Test finished in March; nobody switched them off | $400 |
| 12 unattached disks | Machines deleted, disks left behind | $96 |
| 300 old snapshots | Daily backups with no rule to delete old ones | $150 |
| A copy of the production database | Made for a demo last year | $350 |
| 2 load balancers with nothing behind them | The app was moved; the balancers were not | $40 |
| Total | $1,036 |
None of these was a big decision. Each was a small thing that nobody owned. Together they cost over $12,000 a year, in one account.
3. Hands-on (5 min: no account needed)
1. Think of a shared drive or email inbox you use at work.2. Count the files or folders nobody has opened in a year.3. For each, ask: who owns it? Would anyone notice if it were gone?4. Now imagine each one costs a few dollars a month, every month.5. Write down the three habits from this lesson that would stop the pile growing.The same questions (who owns it, would anyone notice, does it have an end date) are how teams clean up cloud sprawl.
4. Knowledge check
Q1
What is cloud sprawl?
A. A provider’s plan to open new regions around the world
B. Resources piling up faster than anyone tidies them away
C. A sudden spike in visitors to a website
D. A type of discount for using many services
Show answer
Correct: B. Sprawl is the slow build-up of resources that are no longer needed but are still billing.
Q2
Why do people often leave untagged resources in a shared account alone?
A. They are not sure who owns them and fear deleting something important
B. The provider does not allow untagged resources to be deleted
C. Untagged resources do not appear on the bill
D. Deleting a resource always costs more than keeping it
Show answer
Correct: A. With no owner to ask, deleting feels risky, so things stay. Untagged resources can be deleted and do appear on the bill.
Q3
Which sign on a bill most suggests sprawl?
A. Costs that rise when new customers sign up
B. Production running in the region where customers are
C. Snapshot costs that only ever go up, month after month
D. A one-off charge for a support plan
Show answer
Correct: C. Storage and snapshot lines that grow without stopping usually mean nothing is ever deleted. A and B are normal, expected costs.
5. Apply
Pick the three largest lines on a cloud bill that you cannot explain. For each, find out who owns it and whether it is still needed. If nobody can answer, that is sprawl, and it is usually the easiest money to save.
Related lessons
- L3, Who is allowed to create what
- I.3 L2: Why the meter does not stop when nobody is using it
- I.5: How software gets onto it (next)