Disaster recovery strategies (backup, pilot light, warm standby) in AWS - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is the backup disaster recovery strategy?

Backup means saving copies of your data and system configurations regularly. If something breaks, you restore from these saved copies. It’s like having a photo album to remember important moments.

intermediate

Explain the pilot light disaster recovery strategy.

Pilot light keeps a small, basic version of your system running in the cloud. When disaster strikes, you quickly add more resources to make it fully active. Think of it like a small flame ready to light a big fire.

intermediate

What does the warm standby strategy involve?

Warm standby means having a scaled-down but working copy of your system always running. It can take over quickly if the main system fails. It’s like having a backup car ready to drive anytime.

intermediate

Which disaster recovery strategy is the fastest to recover but costs more to maintain?

Warm standby is the fastest to recover because it’s already running, but it costs more since resources are always active.

beginner

Why might a company choose the backup strategy over pilot light or warm standby?

Backup is the cheapest option because you only pay for storage, not running systems. It’s good if you can afford longer downtime and want to save money.

Which disaster recovery strategy keeps a minimal version of your system running to quickly scale up when needed?

A Pilot light

B Backup

C Warm standby

D Cold site

Pilot light keeps a small, basic system running that can be quickly scaled up.

Which strategy involves restoring data from saved copies after a disaster?

A Backup

B Pilot light

C Warm standby

D Hot site

Backup means restoring from saved data copies.

What is a key advantage of the warm standby strategy?

A No running resources

B Lowest cost

C No need for backups

D Fast recovery time

Warm standby allows fast recovery because the system is already running.

Which disaster recovery strategy is usually the cheapest to maintain?

A Warm standby

B Backup

C Hot standby

D Pilot light

Backup is cheapest because it only stores data without running systems.

If a company wants minimal downtime but lower cost than warm standby, which strategy fits best?

A Backup

B Cold site

C Pilot light

D No disaster recovery

Pilot light balances cost and recovery speed.

Describe the differences between backup, pilot light, and warm standby disaster recovery strategies.

Think about how much is running and how fast recovery happens.

Explain why a business might choose pilot light over backup or warm standby.

Consider cost versus recovery speed.

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