Disaster recovery strategies (backup, pilot light, warm standby) in AWS - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to create an S3 bucket for backup storage.

AWS

aws s3api create-bucket --bucket [1] --region us-east-1

Drag options to blanks, or click blank then click option'

Abackup-bucket

Bbackup123

Cmybucket

Dmy-backup-bucket-123

Attempts:

3 left

💡 Hint

Common Mistakes

Using a bucket name that is too generic or already taken.

The bucket name must be globally unique. 'my-backup-bucket-123' is a valid unique name.

2fill in blank

medium

Complete the code to launch a pilot light EC2 instance in the us-west-2 region.

AWS

aws ec2 run-instances --image-id ami-0abcdef1234567890 --count 1 --instance-type [1] --region us-west-2

Drag options to blanks, or click blank then click option'

At3.nano

Bm5.large

Cc5.xlarge

Dt2.micro

Attempts:

3 left

💡 Hint

Common Mistakes

Choosing an instance too small to run essential services.

For pilot light, a moderate instance like 'm5.large' is suitable to keep minimal services running.

3fill in blank

hard

Fix the error in the CloudFormation snippet to define a warm standby RDS instance.

AWS

"Resources": {"WarmStandbyDB": {"Type": "AWS::RDS::DBInstance", "Properties": {"DBInstanceClass": "[1]", "Engine": "mysql", "MultiAZ": true}}}

Drag options to blanks, or click blank then click option'

Adb.t2.micro

Bdb.m4.large

Cdb.r5.large

Ddb.t3.medium

Attempts:

3 left

💡 Hint

Common Mistakes

Using a small instance class that can't handle production load.

Warm standby requires a robust instance like 'db.r5.large' to handle failover smoothly.

4fill in blank

hard

Fill both blanks to configure a pilot light environment with minimal resources.

AWS

PilotLightConfig: {InstanceType: [1], StorageType: [2]

Drag options to blanks, or click blank then click option'

At3.small

Bgp2

Cio1

Dt2.micro

Attempts:

3 left

💡 Hint

Common Mistakes

Choosing expensive storage or too large instances for pilot light.

Use 't3.small' for a small instance and 'gp2' for general purpose storage in pilot light.

5fill in blank

hard

Fill all three blanks to define a warm standby setup with auto-scaling and health checks.

AWS

WarmStandbySetup: {AutoScalingGroupName: [1], HealthCheckType: [2], MinSize: [3]

Drag options to blanks, or click blank then click option'

A"WarmStandbyASG"

B"EC2"

C1

D0

Attempts:

3 left

💡 Hint

Common Mistakes

Setting MinSize to 0, which stops standby instances.

The Auto Scaling group name is 'WarmStandbyASG', health checks use 'EC2', and minimum size is 1 to keep standby running.

Practice

1. Which disaster recovery strategy involves keeping a minimal version of your environment running to quickly scale up after a failure?

easy

A. Pilot light

B. Backup

C. Warm standby

D. Cold standby

Solution

1. Step 1: Understand pilot light strategy

   Pilot light keeps a minimal core of your environment running, like a small copy of critical systems.

2. Step 2: Compare with other strategies

   Backup stores data but requires full rebuild; warm standby runs a scaled-down version ready to take over; cold standby is offline.

3. Final Answer:

   Pilot light -> Option A

4. Quick Check:

   Minimal running core = Pilot light [OK]

Hint: Minimal running core means pilot light strategy [OK]

Common Mistakes:

• Confusing warm standby with pilot light
• Thinking backup keeps systems running
• Assuming cold standby is always active

2. Which AWS service is commonly used to create backups for disaster recovery?

easy

A. Amazon S3

B. Amazon EC2

C. AWS Lambda

D. Amazon VPC

Solution

1. Step 1: Identify backup storage service

   Amazon S3 is designed for durable, scalable storage, ideal for backups.

2. Step 2: Exclude other services

   EC2 is compute, Lambda is serverless code, VPC is networking, none are primarily for backups.

3. Final Answer:

   Amazon S3 -> Option A

4. Quick Check:

   Backup storage = Amazon S3 [OK]

Hint: Backup storage in AWS is Amazon S3 [OK]

Common Mistakes:

• Choosing EC2 as backup storage
• Confusing Lambda with storage
• Selecting VPC for backups

3. Given a warm standby setup in AWS, which of the following best describes its state before a disaster occurs?

medium

A. Fully scaled production environment running in parallel

B. Minimal core systems running, rest offline

C. No environment running, only backups stored

D. Scaled-down but fully functional environment running

Solution

1. Step 1: Understand warm standby state

   Warm standby runs a scaled-down but fully functional environment ready to take over quickly.

2. Step 2: Compare with other options

   Fully scaled parallel is active-active, minimal core is pilot light, no environment is backup only.

3. Final Answer:

   Scaled-down but fully functional environment running -> Option D

4. Quick Check:

   Warm standby = scaled-down functional environment [OK]

Hint: Warm standby runs scaled-down functional environment [OK]

Common Mistakes:

• Confusing warm standby with full production
• Mixing pilot light with warm standby
• Thinking backup means no running environment

4. You set up a pilot light disaster recovery strategy but notice recovery time is longer than expected. What is the most likely cause?

medium

A. Backups are stored in Amazon S3

B. The pilot light environment is not fully configured and requires manual scaling

C. Warm standby environment is running at full capacity

D. The primary environment is still active

Solution

1. Step 1: Analyze pilot light recovery process

   Pilot light requires scaling up minimal systems to full production, so incomplete setup delays recovery.

2. Step 2: Exclude unrelated options

   Backups in S3 are normal; warm standby running full is unrelated; primary active is normal operation.

3. Final Answer:

   The pilot light environment is not fully configured and requires manual scaling -> Option B

4. Quick Check:

   Pilot light slow recovery = incomplete setup [OK]

Hint: Incomplete pilot light setup causes slow recovery [OK]

Common Mistakes:

• Blaming backups for slow recovery
• Confusing warm standby with pilot light
• Assuming primary environment affects recovery time

5. A company wants a disaster recovery solution that balances cost and recovery speed. They want a system running at all times but at reduced capacity, ready to scale up quickly. Which strategy should they choose?

hard

A. Backup only

B. Pilot light

C. Warm standby

D. Cold standby

Solution

1. Step 1: Understand company needs

   They want a running system at reduced capacity that can scale quickly, balancing cost and speed.

2. Step 2: Match needs to strategies

   Backup only is slow recovery; pilot light is minimal core only; cold standby is offline; warm standby runs scaled-down environment ready to scale.

3. Final Answer:

   Warm standby -> Option C

4. Quick Check:

   Running reduced capacity system = Warm standby [OK]

Hint: Running reduced capacity system means warm standby [OK]

Common Mistakes:

• Choosing pilot light for running full system
• Confusing backup with standby strategies
• Selecting cold standby for fast recovery