Failover routing for disaster recovery in AWS - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is failover routing in the context of disaster recovery?

Failover routing automatically switches traffic from a primary site to a backup site when the primary site fails, ensuring continuous service availability.

beginner

Which AWS service is commonly used to implement failover routing?

Amazon Route 53 is used to implement failover routing by monitoring health checks and routing traffic to healthy endpoints.

intermediate

What role do health checks play in failover routing?

Health checks monitor the status of the primary endpoint. If the health check fails, Route 53 routes traffic to the secondary endpoint.

intermediate

What is the difference between active-passive and active-active failover routing?

Active-passive routing sends traffic to the primary site until it fails, then switches to the backup. Active-active routing sends traffic to multiple sites simultaneously for load sharing and redundancy.

intermediate

Why is DNS TTL important in failover routing?

DNS TTL (Time to Live) controls how long DNS responses are cached. A low TTL helps faster failover by reducing caching time, so clients get updated routing quickly.

Which AWS service helps route traffic during failover?

A Amazon S3

B Amazon Route 53

C AWS Lambda

D Amazon EC2

Amazon Route 53 manages DNS and supports failover routing by monitoring endpoint health.

What triggers failover routing to switch traffic to a backup site?

A Health check failure

B User request

C Manual DNS update

D Scheduled maintenance

Failover routing switches when health checks detect the primary site is unhealthy.

In failover routing, what does a low DNS TTL value help with?

A Increased latency

B Longer caching

C Faster traffic switching

D Slower DNS resolution

Low TTL reduces caching time, allowing clients to get updated DNS info quickly during failover.

Which failover routing type sends traffic to multiple sites at the same time?

A Manual failover

B Active-passive

C Static routing

D Active-active

Active-active routing distributes traffic across multiple healthy sites simultaneously.

What is the main purpose of failover routing?

A Ensure service availability during failures

B Increase DNS caching

C Reduce server load

D Backup data storage

Failover routing keeps services running by switching traffic to backup sites when failures occur.

Explain how failover routing works in AWS for disaster recovery.

Think about how Route 53 monitors and switches traffic when a site fails.

Describe the difference between active-passive and active-active failover routing.

Consider how traffic is distributed in each method.