S3 lifecycle rules in AWS - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ service_behavior

intermediate

What happens when an S3 lifecycle rule transitions objects to Glacier after 30 days?

You have an S3 bucket with a lifecycle rule that moves objects to Glacier storage class after 30 days. What is the expected behavior for objects older than 30 days?

A Objects older than 30 days are immediately deleted from S3 and only stored in Glacier.

B Objects older than 30 days are transitioned to Glacier storage class but remain accessible with a retrieval delay.

C Objects older than 30 days remain in S3 Standard storage and are not moved.

D Objects older than 30 days are copied to Glacier but also remain in S3 Standard storage.

💡 Hint

Think about how S3 lifecycle transitions work with Glacier storage class.

Lifecycle rules transition objects to Glacier storage class after the specified days. Objects remain in Glacier and are not immediately deleted. Accessing them requires a retrieval process that can take time.

❓ Configuration

intermediate

Which lifecycle rule configuration deletes objects after 365 days?

Choose the correct JSON snippet for an S3 lifecycle rule that deletes objects 365 days after creation.

A { "Rules": [{ "ID": "DeleteAfter365", "Status": "Enabled", "Expiration": { "Days": 365 } }] }

B { "Rules": [{ "ID": "DeleteAfter365", "Status": "Enabled", "Transition": { "Days": 365, "StorageClass": "GLACIER" } }] }

C { "Rules": [{ "ID": "DeleteAfter365", "Status": "Enabled", "AbortIncompleteMultipartUpload": { "DaysAfterInitiation": 365 } }] }

D { "Rules": [{ "ID": "DeleteAfter365", "Status": "Enabled", "Expiration": { "Date": "365" } }] }

💡 Hint

Expiration rules use the 'Days' field to specify deletion timing.

The 'Expiration' property with 'Days' set to 365 correctly deletes objects 365 days after creation. Transition moves storage class, not deletion.

❓ security

advanced

What is the security risk of enabling lifecycle rules that permanently delete objects without versioning?

You enable lifecycle rules that permanently delete objects after 30 days on a bucket without versioning. What is the main security risk?

A Lifecycle rules automatically encrypt deleted objects, preventing data leaks.

B Objects can be recovered after deletion using versioning snapshots.

C Objects are archived to Glacier before deletion, so no data is lost.

D Deleted objects cannot be recovered, risking accidental data loss.

💡 Hint

Consider what happens when versioning is not enabled and objects are deleted.

Without versioning, deleted objects are permanently lost. This can cause accidental data loss if lifecycle rules delete objects automatically.

❓ Architecture

advanced

How to design lifecycle rules for cost optimization with frequent access and archival?

You have a bucket with objects accessed frequently for 60 days, then rarely accessed for 180 days, then archived. Which lifecycle rule sequence optimizes cost?

A Transition to GLACIER after 60 days, then to STANDARD_IA after 180 days, then delete after 365 days.

B Delete after 60 days, transition to GLACIER after 180 days, then to STANDARD_IA after 365 days.

C Transition to STANDARD_IA after 60 days, then to GLACIER after 180 days, then delete after 365 days.

D Keep all objects in STANDARD storage for 365 days, then delete.

💡 Hint

Think about storage classes for frequent and infrequent access and cost savings.

STANDARD_IA is cheaper for infrequent access after 60 days, GLACIER is cheaper for archival after 180 days, and deleting after 365 days saves storage costs.

✅ Best Practice

expert

What is the best practice to prevent accidental deletion with lifecycle rules on a versioned bucket?

You have enabled versioning on an S3 bucket and lifecycle rules that delete objects after 30 days. What is the best practice to avoid accidental permanent deletion?

A Configure lifecycle rules to delete only non-current versions after 30 days and keep current versions.

B Disable versioning to simplify lifecycle rule management.

C Set lifecycle rules to delete all versions immediately after 30 days.

D Use lifecycle rules to transition all versions to GLACIER instead of deleting.

💡 Hint

Consider how versioning interacts with lifecycle expiration of current and non-current versions.

Deleting only non-current versions preserves the latest object versions and prevents accidental permanent loss. Disabling versioning or deleting all versions immediately risks data loss.

Practice

1. What is the main purpose of an S3 lifecycle rule?

easy

A. To automatically move or delete files based on time to save costs

B. To manually upload files to S3 buckets

C. To create backups of files in S3

D. To encrypt files stored in S3

Solution

1. Step 1: Understand lifecycle rule purpose

   S3 lifecycle rules automate management of files by moving or deleting them after a set time.

2. Step 2: Compare options with lifecycle rule function

   Only To automatically move or delete files based on time to save costs describes automatic moving or deleting files to save costs, which matches lifecycle rules.

3. Final Answer:

   To automatically move or delete files based on time to save costs -> Option A

4. Quick Check:

   Lifecycle rules automate file management = C [OK]

Hint: Lifecycle rules automate file moves or deletes by time [OK]

Common Mistakes:

• Confusing lifecycle rules with manual upload
• Thinking lifecycle rules create backups
• Assuming lifecycle rules encrypt files

2. Which of the following is the correct JSON snippet to define a lifecycle rule that deletes objects after 30 days?

easy

A. {"Rules": [{"Status": "Disabled", "Expiration": {"Days": 30}}]}

B. {"Rules": [{"Status": "Enabled", "Transition": {"Days": 30}}]}

C. {"Rules": [{"Status": "Enabled", "Expiration": {"Days": 30}}]}

D. {"Rules": [{"Status": "Enabled", "Expiration": {"Date": 30}}]}

Solution

1. Step 1: Identify correct lifecycle rule syntax for expiration

   The expiration action uses "Expiration" with "Days" key and rule must be "Enabled".

2. Step 2: Check each option for correct keys and values

   {"Rules": [{"Status": "Enabled", "Expiration": {"Days": 30}}]} uses "Expiration" with "Days":30 and "Status":"Enabled" which is correct. {"Rules": [{"Status": "Enabled", "Transition": {"Days": 30}}]} uses "Transition" which is for storage class change, not deletion. {"Rules": [{"Status": "Disabled", "Expiration": {"Days": 30}}]} disables the rule. {"Rules": [{"Status": "Enabled", "Expiration": {"Date": 30}}]} uses "Date" instead of "Days" which is invalid.

3. Final Answer:

   {"Rules": [{"Status": "Enabled", "Expiration": {"Days": 30}}]} -> Option C

4. Quick Check:

   Expiration with Days and Enabled status = A [OK]

Hint: Expiration uses "Days" and rule must be enabled [OK]

Common Mistakes:

• Using Transition instead of Expiration for deletion
• Setting rule status to Disabled
• Using Date instead of Days for expiration

3. Given this lifecycle rule snippet, what happens to objects after 60 days?

{
  "Rules": [{
    "Status": "Enabled",
    "Prefix": "logs/",
    "Transition": {"Days": 60, "StorageClass": "GLACIER"}
  }]
}

medium

A. Objects in the 'logs/' folder are moved to Glacier storage after 60 days

B. Objects in the 'logs/' folder are deleted after 60 days

C. All objects in the bucket are moved to Glacier after 60 days

D. Objects in the 'logs/' folder are archived immediately

Solution

1. Step 1: Understand the Transition action with Prefix

   The rule targets objects with prefix "logs/" and transitions them to Glacier after 60 days.

2. Step 2: Analyze options against rule behavior

   Objects in the 'logs/' folder are moved to Glacier storage after 60 days correctly states objects in 'logs/' move to Glacier after 60 days. Objects in the 'logs/' folder are deleted after 60 days incorrectly says deletion. All objects in the bucket are moved to Glacier after 60 days incorrectly applies to all objects, not just prefix. Objects in the 'logs/' folder are archived immediately says immediate archive which is wrong.

3. Final Answer:

   Objects in the 'logs/' folder are moved to Glacier storage after 60 days -> Option A

4. Quick Check:

   Transition with prefix moves files after days = A [OK]

Hint: Transition moves files after days, prefix limits target [OK]

Common Mistakes:

• Confusing Transition with Expiration (deletion)
• Ignoring the prefix filter
• Assuming all bucket objects are affected

4. You wrote this lifecycle rule but it does not delete files after 90 days:

{
  "Rules": [{
    "Status": "Enabled",
    "Expiration": {"Days": 90}
  }]
}

What is the likely problem?

medium

A. Missing a required rule ID

B. Status should be set to Disabled to activate

C. Expiration action cannot be used without Transition

D. Rule is missing a filter or prefix to target objects

Solution

1. Step 1: Recall S3 lifecycle rule required fields

   Every lifecycle rule requires a unique "ID" field only if using AWS CLI or SDKs; however, in JSON configuration for S3 console, "ID" is optional. Filter or prefix is required to target objects; otherwise, the rule applies to all objects.

2. Step 2: Analyze given rule

   The rule lacks a filter or prefix, so it applies to all objects. If files are not deleting, likely the rule is not targeting the intended objects. Missing "ID" is not always mandatory (A wrong). Status "Enabled" is correct (B wrong). Expiration works standalone (C wrong). Filter or prefix is needed to target specific objects (D correct).

3. Final Answer:

   Rule is missing a filter or prefix to target objects -> Option D

4. Quick Check:

   Missing filter or prefix means rule may not target intended objects = D [OK]

Hint: Filter or prefix is needed to target objects for deletion [OK]

Common Mistakes:

• Believing filter or prefix is optional (A)
• Thinking Expiration requires Transition (C)
• Status should be Disabled to activate (B)

5. You want to save costs by moving files older than 30 days to STANDARD_IA storage and delete files older than 365 days, but only for files in the archive/ folder. Which lifecycle rule setup achieves this?

hard

A. {
"Rules": [{
"Status": "Enabled",
"Prefix": "archive/",
"Transition": {"Days": 365, "StorageClass": "STANDARD_IA"},
"Expiration": {"Days": 30}
}]
}

B. {
"Rules": [{
"Status": "Enabled",
"Filter": {"Prefix": "archive/"},
"Transitions": [{"Days": 30, "StorageClass": "STANDARD_IA"}],
"Expiration": {"Days": 365}
}]
}

C. {
"Rules": [{
"Status": "Enabled",
"Filter": {"Prefix": "archive/"},
"Transition": {"Days": 365, "StorageClass": "STANDARD_IA"},
"Expiration": {"Days": 30}
}]
}

D. {
"Rules": [{
"Status": "Enabled",
"Filter": {"Prefix": "archive/"},
"Transitions": [{"Days": 365, "StorageClass": "STANDARD_IA"}],
"Expiration": {"Days": 30}
}]
}

Solution

1. Step 1: Identify correct keys for multiple transitions and expiration

   Multiple transitions require "Transitions" array. Expiration is separate. Filter with Prefix targets 'archive/'.

2. Step 2: Check each option for correct days and storage class order

   { "Rules": [{ "Status": "Enabled", "Prefix": "archive/", "Transition": {"Days": 365, "StorageClass": "STANDARD_IA"}, "Expiration": {"Days": 30} }] } reverses days and expiration. { "Rules": [{ "Status": "Enabled", "Filter": {"Prefix": "archive/"}, "Transitions": [{"Days": 30, "StorageClass": "STANDARD_IA"}], "Expiration": {"Days": 365} }] } correctly uses "Transitions" array with 30 days to STANDARD_IA and expiration at 365 days, with filter prefix. { "Rules": [{ "Status": "Enabled", "Filter": {"Prefix": "archive/"}, "Transition": {"Days": 365, "StorageClass": "STANDARD_IA"}, "Expiration": {"Days": 30} }] } uses singular "Transition" but reverses days (365 to IA, expire 30). { "Rules": [{ "Status": "Enabled", "Filter": {"Prefix": "archive/"}, "Transitions": [{"Days": 365, "StorageClass": "STANDARD_IA"}], "Expiration": {"Days": 30} }] } reverses days and expiration.

3. Step 3: Choose best practice with multiple transitions

   { "Rules": [{ "Status": "Enabled", "Filter": {"Prefix": "archive/"}, "Transitions": [{"Days": 30, "StorageClass": "STANDARD_IA"}], "Expiration": {"Days": 365} }] } uses "Transitions" array which is best practice for multiple transitions, even if only one here, and matches requirements.

4. Final Answer:

   Rule with Filter prefix 'archive/', Transitions at 30 days to STANDARD_IA, Expiration at 365 days -> Option B

5. Quick Check:

   Multiple transitions use "Transitions" array, filter prefix set = B [OK]

Hint: Use "Transitions" array for multiple moves, filter prefix to target folder [OK]

Common Mistakes:

• Confusing Transition singular vs Transitions array
• Mixing up days for transition and expiration
• Not using filter or prefix to limit scope