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Storage Classes & Lifecycle Policies

In short

Last week's logs get opened daily. Last year's logs maybe once, during an audit. Paying the same price for both is like renting a front-row seat for a box you never open.

Object storage offers multiple tiers (frequent access, infrequent access, archive) at different price points — lifecycle policies automatically move data between tiers as it ages, reducing storage costs without manual work.

The blob character on a stool pushes a trunk of sweaters onto a loft.

Think of it like this

Cupboard, loft, storeroom

Daily clothes go in the cupboard. Winter sweaters go up to the loft in March. Old school uniforms go to the storeroom trunk. Nobody moves them every day; it happens on a schedule. Lifecycle policies do that for your data.

Watch it happen

One log file's life

Standard

Standard-IA

Glacier

Deep Archive

Delete

1/5Day 0: the log lands in S3 Standard. Fast access, highest storage price.

The big ideas

What you need to know

Hot to cold tiers

Each class trades storage price against access speed and retrieval cost. Colder is cheaper to keep, costlier to read.

Rules by age

Lifecycle rules move or delete objects after N days, filtered by prefix or tag. Set once, runs forever.

Minimum durations

Colder classes charge for a minimum time, like 30, 90 or 180 days. Moving data out early still costs that.

Intelligent-Tiering

Unsure of access patterns? This class moves objects between tiers automatically for a small monitoring fee.

See it in code

Walk through the code

json

1{2  "Rules": [{3    "ID": "logs-tiering",4    "Filter": { "Prefix": "logs/" },5    "Status": "Enabled",6    "Transitions": [7      { "Days": 30,  "StorageClass": "STANDARD_IA" },8      { "Days": 90,  "StorageClass": "GLACIER" },9      { "Days": 180, "StorageClass": "DEEP_ARCHIVE" }10    ],11    "Expiration": { "Days": 365 }12  }]13}

1/3This rule only touches keys under logs/, and it's switched on.

Apply with aws s3api put-bucket-lifecycle-configuration --bucket my-logs --lifecycle-configuration file://rule.json

Save yourself the pain

Common mistakes

Oops

Moving tiny files to Glacier to save money.

Do this instead

Very small objects carry per-object overhead in cold tiers. Bundle small files or keep them in a warmer class.

Oops

Archiving data the app still reads every week.

Do this instead

Check access patterns first. Frequent reads from IA or Glacier can cost more than just leaving it in Standard.

Your mission

Write a lifecycle rule

~20 min

Quick check

Audit logs must be kept 7 years but are almost never read. Which approach is cheapest?

Go deeper

1Set up a lifecycle policy moving objects to a cheaper storage class after a set number of days.
2Learn the retrieval time and cost trade-offs between different storage classes.
3Practice reasoning about which storage class fits a given access pattern.