Validation Quiz - MODULE 10
This 30-question quiz allows you to validate your knowledge of Route 53 and DNS before moving on to the practical lab.
Question 1
What is DNS?
A) A storage service
B) Domain Name System - translates domain names into IP addresses
C) A security protocol
D) A type of database
See the answer
Answer: B
DNS (Domain Name System) is the system that translates readable domain names (www.example.com) into IP addresses (192.0.2.1) that computers use to communicate. It's like the Internet's directory.
Question 2
What is Route 53?
A) A network route
B) AWS's DNS and domain registration service
C) A Load Balancer
D) A VPN
See the answer
Answer: B
Amazon Route 53 is AWS's highly available and scalable DNS service. It allows you to register domain names, route Internet traffic to AWS resources, and check the health of resources.
Question 3
Why is Route 53 called "53"?
A) It's the 53rd AWS service
B) DNS uses port 53
C) It's a random number
D) Reference to the year 1953
See the answer
Answer: B
The name refers to port 53, which is the standard port used by the DNS protocol for queries and responses. It's a technical reference to the DNS protocol.
Question 4
What is a Hosted Zone in Route 53?
A) A geographical zone
B) A container for a domain's DNS records
C) An availability zone
D) A data center
See the answer
Answer: B
A Hosted Zone is a container that stores the DNS records for a domain. There are two types: public (accessible from the Internet) and private (accessible only from one or more VPCs).
Question 5
What is the difference between a public and private Hosted Zone?
A) None
B) Public accessible from the Internet, Private accessible only from VPCs
C) Private is cheaper
D) Public is faster
See the answer
Answer: B
A public Hosted Zone responds to DNS queries from the Internet for a public domain. A private Hosted Zone responds only to queries from associated VPCs, useful for internal DNS resolution.
Question 6
What is an A record?
A) An authentication record
B) A record that maps a domain name to an IPv4 address
C) An alert record
D) An administrative record
See the answer
Answer: B
The A (Address) record maps a domain name to an IPv4 address. Example: www.example.com -> 192.0.2.1. It's the most fundamental type of record.
Question 7
What is an AAAA record?
A) A quadruple A record
B) A record that maps a domain name to an IPv6 address
C) An advanced alias record
D) An advanced authentication record
See the answer
Answer: B
The AAAA record maps a domain name to an IPv6 address (128 bits). The name "AAAA" comes from the fact that an IPv6 address is 4 times longer than an IPv4.
Question 8
What is a CNAME record?
A) A certificate record
B) An alias pointing to another domain name
C) A configuration record
D) A contact record
See the answer
Answer: B
The CNAME (Canonical Name) record creates an alias from one name to another. Example: www.example.com -> example.com. CNAME cannot be used at the domain apex (zone apex).
Question 9
Why can't you use CNAME at the domain apex?
A) It's an AWS limitation
B) DNS specifications prohibit it because CNAME cannot coexist with other records
C) It's too expensive
D) It's slower
See the answer
Answer: B
The DNS specification (RFC) prohibits CNAME at the apex because a CNAME must be the only record for a name. However, the apex requires mandatory NS and SOA records. Route 53 ALIAS solves this problem.
Question 10
What is an ALIAS record in Route 53?
A) A standard DNS alias
B) An AWS proprietary extension allowing pointing to AWS resources at the apex
C) A security alias
D) A type of MX record
See the answer
Answer: B
ALIAS is a Route 53 extension (not a DNS standard) that allows pointing to AWS resources (ALB, CloudFront, S3, etc.) including at the domain apex. ALIAS queries are free to AWS resources.
Question 11
Which AWS resources can be targeted by an ALIAS record?
A) Only EC2
B) ELB, CloudFront, S3, API Gateway, another Route 53 record, etc.
C) Only S3
D) Only databases
See the answer
Answer: B
ALIAS can point to: Elastic Load Balancers, CloudFront distributions, S3 buckets configured as websites, API Gateway, VPC endpoints, another record in the same Hosted Zone. Not directly to EC2 instances.
Question 12
What is TTL (Time To Live)?
A) The expiration time of a certificate
B) The duration a DNS resolver caches a record
C) The lifespan of an instance
D) A connection timeout
See the answer
Answer: B
TTL defines how long (in seconds) a DNS resolver can cache the response before re-querying. A low TTL (60s) allows quick changes but more queries. A high TTL (86400s) reduces load but delays changes.
Question 13
Which TTL to choose before a planned DNS change?
A) High TTL
B) Lower the TTL to a low value several hours before the change
C) TTL doesn't change anything
D) Remove the TTL
See the answer
Answer: B
Before a planned change (migration), lower the TTL (e.g., 60s) at least 48h in advance. Caches will expire and during the change, propagation will be quick. Afterward, raise the TTL to reduce DNS load.
Question 14
What is Simple routing in Route 53?
A) The most complex routing
B) A record that returns one or more values without special logic
C) Routing with Load Balancer
D) Geographic routing
See the answer
Answer: B
Simple routing returns the configured values without special processing. If multiple IPs are configured, Route 53 returns them all and the client randomly chooses one. No health check possible.
Question 15
What is Weighted routing?
A) Routing based on server weight
B) Traffic distribution according to weights assigned to each record
C) Routing based on load
D) Routing based on latency
See the answer
Answer: B
Weighted routing allows distributing traffic according to weights. Example: 70% to resource A (weight 70), 30% to resource B (weight 30). Useful for canary deployments or A/B testing.
Question 16
What is Latency-based routing?
A) Routing based on date
B) Routing to the resource with the lowest latency for the user
C) Routing based on application response time
D) Routing based on TTL
See the answer
Answer: B
Latency-based routing directs users to the AWS region with the lowest latency from their location. Route 53 measures network latency and automatically chooses the best destination.
Question 17
What is Failover routing?
A) Routing to a backup server
B) Automatic routing to a secondary resource if the primary fails the health check
C) Routing in case of user error
D) Routing based on cost
See the answer
Answer: B
Failover routing uses health checks to determine if the primary resource is healthy. If it fails, traffic is automatically directed to the secondary resource (backup site, static page).
Question 18
What is Geolocation routing?
A) Routing based on GPS coordinates
B) Routing according to the user's geographic location (country, continent)
C) Routing to the nearest server
D) Routing based on language
See the answer
Answer: B
Geolocation routing routes according to the user's geographic location: continent, country, or state/province. Useful for compliance (data in Europe), content localization, or license restrictions.
Question 19
What is Geoproximity routing?
A) Routing based on server proximity to each other
B) Routing based on geographic proximity with bias possibility
C) Routing based on speed
D) Routing based on borders
See the answer
Answer: B
Geoproximity routes to the geographically closest resource with a configurable "bias". The bias expands or shrinks a resource's area. Useful for gradually shifting traffic to new regions.
Question 20
What is a Route 53 Health Check?
A) A health examination
B) A periodic check of an endpoint's availability
C) A security audit
D) A billing check
See the answer
Answer: B
A Route 53 Health Check periodically checks if an endpoint (IP, domain, another health check) is available. It can check HTTP/HTTPS, TCP, or the status of other health checks. Used for failover and intelligent routing.
Question 21
What can an HTTP/HTTPS Health Check verify?
A) Only if the port is open
B) The response code (2xx/3xx) and optionally a string in the body
C) Only the SSL certificate
D) Only the response speed
See the answer
Answer: B
An HTTP/HTTPS Health Check verifies that the response code is 2xx or 3xx. You can also configure a string matching check to verify that a specific text appears in the first 5120 bytes of the response.
Question 22
What is a Calculated Health Check?
A) A mathematical health check
B) A health check that combines the status of several other health checks
C) A health check with formula
D) An automatic health check
See the answer
Answer: B
A Calculated Health Check monitors several child health checks and reports "healthy" according to logic: at least X children healthy, all healthy, or at least 1 healthy. Useful for creating complex health checks.
Question 23
How does Route 53 integrate with CloudWatch?
A) No integration
B) Health checks publish metrics, you can create CloudWatch alarms
C) Only for logs
D) Only for billing
See the answer
Answer: B
Route 53 health checks publish metrics to CloudWatch (HealthCheckStatus, ConnectionTime, etc.). You can create CloudWatch alarms to be notified when a health check fails.
Question 24
What is DNS resolution in a VPC?
A) A type of subnet
B) The DNS service provided by AWS to resolve names from a VPC
C) A Security Group
D) A route table
See the answer
Answer: B
AWS provides a DNS resolver in each VPC (at address base+2, e.g., 10.0.0.2). It resolves public DNS names and private names (private Hosted Zones). enableDnsSupport and enableDnsHostnames control this behavior.
Question 25
How to use a custom domain with an ALB?
A) Not possible
B) Create an ALIAS or CNAME record pointing to the ALB's DNS name
C) Modify the ALB's name
D) Use the ALB's IP
See the answer
Answer: B
Create a Route 53 record (ALIAS recommended, or CNAME for subdomains) pointing to the ALB's DNS name. ALIAS is preferred as it's free for AWS resources and works at the apex.
Question 26
What is "DNS propagation"?
A) DNS speed
B) The time it takes for DNS changes to be reflected globally
C) DNS server replication
D) DNS installation
See the answer
Answer: B
DNS propagation is the time it takes for changes (new records, modifications) to be reflected everywhere on the Internet. It depends on the TTL and can take from a few minutes to 48 hours depending on caches.
Question 27
How to speed up DNS propagation during a change?
A) Impossible
B) Use a low TTL before the change
C) Pay more
D) Use multiple domains
See the answer
Answer: B
Lower the TTL several hours before the change (at least longer than the old TTL). Resolvers will expire their caches, and during the change, they will query Route 53 for the new values quickly.
Question 28
What is nslookup?
A) A tool to search for servers
B) A command-line tool to query DNS servers
C) A web browser
D) An AWS service
See the answer
Answer: B
nslookup (and dig) are tools to query DNS servers. They allow you to check which IP is returned for a domain, which DNS server responds, and diagnose DNS issues.
Question 29
In a failover scenario, what is a "primary" vs "secondary" record?
A) Primary and secondary in terms of priority
B) The primary receives traffic if healthy, the secondary takes over if the primary fails
C) Primary is faster
D) Secondary is more secure
See the answer
Answer: B
In Failover routing, the primary is the main resource associated with a health check. As long as it is healthy, all traffic goes there. If the health check fails, traffic switches to the secondary (backup).
Question 30
How to test a DNS failover without a real outage?
A) Wait for a real outage
B) Configure the health check to fail (invalid endpoint) or block the health check
C) It's not testable
D) Delete the primary
See the answer
Answer: B
Test by intentionally causing the health check to fail: stop the service on the endpoint, modify the Security Group to block Route 53 checkers, or change the health check path to a non-existent URL. Verify the switch.
Result
Count your correct answers:
- 27-30: Excellent - You master Route 53 and DNS
- 22-26: Good - A few points to review
- 17-21: Average - Review the course before the lab
- Less than 17: Insufficient - Retake the course from the beginning
Proceed to the Failover Lab once you have achieved at least 22 correct answers.