AWS Route 53 Interview Questions and Answers

AWS Route 53 Interview Questions and Answers

Here are commonly asked AWS Route 53 Interview Questions questions and answers to prepare you for your interview:

AWS Route 53 Interview Questions

Q1. What is the AWS Route 53?

Q2. Explain Features of Amazon Route 53.

Q3. What are the benefits of Route 53?

Q4. What are three services available on Route 53?

Q5. How Amazon Route 53 Works?

Q6. Why it is called Route 53?

Q7. Does Route 53 Do load balancing?

Q8. What are Name servers?

Q9. What is a resource record?

Q10. What are zones?

Q11. What is a DNS name or alias?

Q12. What are “A” and “Cname” record?

Q13. How can we add a load balancer to Route 53?

Q14. How we can add Cname to Route 53?

Q15. What are some common use cases for Amazon Route 53

Q16. What are DNS records types that Route 53 supports?

Q17. What are Amazon Route 53 Routing Poilicies? 

Q18. What is Simple Routing Policy?

Q19. Explain Weighted Routing Policy

Q20. Explain Latency Routing Policy

Q21. Explain Failover Routing Policy

Q22. Explain Geo Location Routing Policy

Q23. Explain Multi Value Routing Policy

Q24. Explain Amazon Route 53 as a Registrar

Q25. Why would I use Amazon Route 53 instead of Google Domains or GoDaddy?

Q26. What are some alternatives to Amazon Route 53

Q27. What is the standard Time To Live (TTL) setting for entries made in Amazon Route 53

Q28. What’s the difference between a public hosted zone and a private hosted zone in Amazon Route 53?

Q29. Is it possible to route traffic based on user location using Amazon Route 53? If yes, then how?

Q30. Does Amazon Route 53 offer redundancy options?

Q31. What is the default TTL setting for records created in Amazon Route 53?

Q33. What is PTR record. 

Q34. What is SRV record?

Q35. What is TXT record ?

Q36. What is SOA record?

Q37. What is the difference between an Alias record and a CNAME record in Route 53?

Q38. How does Amazon Route 53 ensure high availability and reliability?

Q39. Explain Route 53 Resolvers.

Q40. What are Route 53 Health Checks types?

Q1. What is the AWS Route 53?

AWS’s Route 53 is a scalable and easy-to-use domain name system (DNS) hosting service. DNS services help translate your domain names into IP addresses so that you can communicate across the internet, just like translating someone’s name into their phone number so you can reach them on the phone. 

Amazon Route 53 connects user requests to AWS infrastructure such as Amazon EC2 instances, Elastic Load Balancing load balancers, and Amazon S3 buckets, as well as infrastructure outside of AWS.

Amazon Route 53 also offers several other features such as domain name registration, health checks, and traffic management.

 

Q2. Explain Features of Amazon Route 53.

Features of Amazon Route 53:

Traffic flow—routes end users to the endpoint that should provide the best user experience

Latency-based routing—routes users to the AWS region that provides the lowest latency

Geo DNS—routes users to an endpoint, depending on detected user geography

Private DNS—for users of Amazon VPC, defines custom domain names without exposing DNS information publicly

DNS failover—automatically redirects users to an alternative service in case of outage

Health checks—monitors health and performance of applications

Domain registration—AWS acts as a domain registrar, allowing you to select domain names and register for them with the AWS console

Weighted round-robin load balancing—spreads traffic between several services via a round-robin algorithm.

 

Q3. What are the benefits of Route 53?

Amazon Route 53 is a service that connects a user’s request to AWS infrastructure.

1) Easy to register your domain − We can purchase all level of domains like .com, .net, .org, etc. directly from Route 53.

2) Highly reliable − Route 53 is built using AWS infrastructure. Its distributed nature towards DNS servers help to ensure a consistent ability to route applications of end users.

3) Scalable − Route 53 is designed in such a way that it automatically handles large volume queries without the user’s interaction.

4) Can be used with other AWS Services − Route 53 also works with other AWS services. It can be used to map domain names to our Amazon EC2 instances, Amazon S3 buckets, Amazon and other AWS resources.

5) Easy to use − It is easy to sign-up, easy to configure DNS settings, and provides quick response to DNS queries.

6) Health Check- Route 53 monitors the health of the application. If an outage is detected, then it automatically redirects the users to a healthy resource.

7) Cost-Effective − Pay only for the domain service and the number of queries that the service answers for each domain.

8) Secure − By integrating Route 53 with AWS (IAM), there is complete control over every user within the AWS account, such as deciding which user can access which part of Route 53.

 

Q4. What are three services available on Route 53?

Amazon’s Route 53 provides three services:

  1. Record creation that stores the human-readable names you want associated with your web domains
  2. Request handling to send web traffic to the appropriate servers
  3. Health checks to make sure traffic isn’t being sent to servers which can’t handle it.

 

Q5. How Does Amazon Route 53 Work?

Amazon Route 53 works by translating domain names into IP addresses. When a user types a domain name in their web browser, the browser sends a DNS query to the nearest DNS server. The DNS server then looks up the IP address for the domain name and returns it to the browser.

When a business uses Amazon Route 53, they can create DNS records for their domain names using the Amazon Route 53 console, API, or CLI. These DNS records contain information such as IP addresses, CNAMEs, and other information that help Route 53 to route traffic to the appropriate endpoint.

When a user requests a domain name, Amazon Route 53 receives the DNS query and looks up the DNS records for the domain name. Based on the routing policies configured by the business, Amazon Route 53 then routes the traffic to the appropriate endpoint.

 

Q6. Why is it called Route 53?

The name AWS Route 53 is derived from Port 53, which handles DNS for both TCP and UDP traffic requests; the phrase Route could relate to routing or a common highway naming convention.

 

Q7. Does Route 53 Do load balancing?

Route 53 is a DNS service that handles global server load balancing by routing requests to the AWS region closest to the requester’s location.

 

Q8. What are Name servers?

Name servers are DNS names or aliases we want to link to our domain name or alias, such as example.com and www.example.com, respectively.

We can create up to 100 name servers for a specific hosted zone.

 

Q9. What is a resource record?

A resource record is a DNS entry (like www.example.com) and a value such as 192.0.3.2 that you want to link to a name server in a hosted zone. These are sometimes referred to as record sets in AWS Route 53.

 

Q10. What are zones?

Zones are the grouping of one or more hosted zones with the same namespace in our AWS account.

As an illustration, if we have two different websites, www1 and www2, they would be kept in two different hosted zones in our AWS account.

Q11. What is a DNS name or alias?

The human readable record we want to link to an endpoint in Route 53 is called a DNS name (e.g., example.com ).

For instance, if someone types google.com into their web browser’s address bar, Route 53 will provide the IP address corresponding to that domain name.

 

Q12. What are “A” and “Cname” record?

 A – This resource record set is used when you want to map a unique hostname (e.g., example.com ) or alias (e.g., www.example.com ) to a single IPv4 address or the associated private IP addresses with an Elastic IP Address or Auto Scaling group.

CNAME – This resource record set is used when you want to map multiple hostnames (e.g., www1, www2, www3…) to a single DNS entry (e.g., example.com).

 

Q13. How can we add a load balancer to Route 53?

Launch the Route 53 console in the AWS Management Console by navigating to https://console.aws.amazon.com/route53/.

  • Select Hosted zones from the navigation pane.
  • Select the hosted zone with the domain name you wish to use to redirect traffic to your load balancer.
  • Create Record by entering the following values: Routing policy, Record name, Alias, Value/Route traffic to, Record type (Select A – IPv4 address), Evaluate target health

Within 60 seconds, changes are normally propagated to all Route 53 servers. When propagation is complete, we can use the name of the alias record you created in this step to send traffic to your load balancer.

 

Q14. How can we add the Cname to Route 53?

A CNAME record cannot be created for the Parent,or Apex domains. An alias record can be used with Route 53 to point the parent domain to other supported alias targets.

 

Q15. What are some common use cases for Amazon Route 53

Amazon Route 53 is used to route users to websites, applications and other services. Common use cases include:

  1. Domain Name Registration: AWS Route 53 enables customers to register domain names and manage their DNS records.
  2. Website Hosting: With AWS Route 53, customers can set up subdomains for websites, map domains to website endpoints, and create redirects for specific URLs.
  3. Reliable and Scalable DNS Service: AWS Route 53 enables customers to route traffic using the power of its global network of DNS servers. It is highly available, scales automatically to handle high DNS query volumes and integrates with other AWS services to improve security, reliability and performance.
  4. Automated Health Checks: Amazon Route 53 makes it easy to detect unhealthy endpoints so that customers can route traffic away from them.
  5. Dynamic DNS Services: AWS Route 53’s API and hosted zones support dynamic DNS services such as round robin load balancing and Geo-DNS.

 

Q16. What are DNS records types that Route 53 supports?

Amazon Route 53 currently supports the following DNS record types:

  1. A (address record)
  2. AAAA (IPv6 address record)
  3. CNAME (canonical name record)
  4. CAA (certification authority authorization)
  5. MX (mail exchange record)
  6. NAPTR (name authority pointer record)
  7. NS (name server record)
  8. PTR (pointer record)
  9. SOA (start of authority record)
  10. SPF (sender policy framework)
  11. SRV (service locator)
  12. TXT (text record)

Amazon Route 53 also offers alias records, which are an Amazon Route 53-specific extension to DNS. You can create alias records to route traffic to selected AWS resources, including Amazon Elastic Load balancers, Amazon CloudFront distributions, AWS Elastic Beanstalk environments, API Gateways, VPC interface endpoints, and Amazon S3 buckets that are configured as websites.

 

Q17. What are Amazon Route 53 Routing Policies? 

1) Simple Routing Policy

2) Weighted Routing Policy

3) Latency Routing Policy

4) Failover Routing Policy

5) Geo Location Routing Policy

6) Multi Value Routing Policy

 

Q18. What is Simple Routing Policy?

In simple routing policy, you can have only one record with multiple IP addresses. If you specify multiple values in record, Route53 returns all values in random order to the user.

Maps a domain to one URL, Use when you need to redirect to a single resource. You can’t attach health checks to simple routing policy. If multiple values are returned, a random one is chosen by the client.

 

Q19. Explain Weighted Routing Policy

Weighted Routing Policy controls the percentage % of the requests that go to specific endpoints. It’s helpful to test 1% of traffic on new app version. It is also helpful to split traffic between two regions. We can associate Health checks with it.

 

Q20. Explain Latency Routing Policy.

It allows you to route your traffic based on lowest network latency for your end user. It redirects to the server that has the least latency close to us also helpful when latency of users is a priority. Latency is evaluated in terms of user to designated AWS Region. For example: Germany may be directed to the US (if that’s the lowest latency)

 

Q21. Explain Failover Routing Policy.

Failover routing lets you route traffic to a resource when the resource is healthy or to a different resource when the first resource is unhealthy. The primary and secondary records can route traffic to anything from an Amazon S3 bucket that is configured as a website to a complex tree of records.

 

Q22. Explain Geo Location Routing Policy.

Geolocation routing lets you choose the resources that serve your traffic based on the geographic location of your users, meaning the location that DNS queries originate from. For example, you might want all queries from Europe to be routed to an ELB load balancer in the Frankfurt region.

 

Q23. Explain Multi Value Routing Policy

It helps distribute DNS responses across multiple resources. For example, use multi value answer routing when you want to associate your routing records with a Route 53 health check.

Use multivalue answer routing when you need to return multiple values for a DNS query and route traffic to multiple IP addresses. Up to 8 healthy records are returned for each Multi Value query. Multi Value is not a substitute for having an ELB.

 

Q24. Explain Amazon Route 53 as a Registrar.

A domain name registrar is an organization that manages the reservation of Internet domain names

Famous names: GoDaddy/Google Domains/Etc… And also… Route53 (e.g. AWS)!

 

Q25. Why would I use Amazon Route 53 instead of Google Domains or GoDaddy?

Amazon Route 53 is a reliable and cost-effective way to route end users to Internet applications by translating human-readable names like www.example.com into the numeric IP addresses like 192.0.2.1 that computers use to connect to each other. Amazon Route 53 is also scalable, so it can grow with your website or application. Additionally, Amazon Route 53 integrates with other AWS services, so you can use it to route end users to your Amazon EC2 instances, Amazon S3 buckets, and other AWS resources.

 

Q26. What are some alternatives to Amazon Route 53?

Some popular alternatives to Amazon Route 53 include Google Cloud DNS, Azure DNS, Cloudflare, DynDNS, and DNS Made Easy. Each of these services offers different features and benefits, so customers should consider their specific needs when deciding which service to use.

  1. Google Cloud DNS is widely used and has robust features and pricing. It allows customers to manage their domain’s DNS configuration with a few clicks and offers accurate responses to queries with low latency.
  2. Azure DNS enables customers to create and manage DNS zones in the cloud, as well as manage their domains and subdomains. It integrates with Azure services, including Virtual Machines and App Services, to ensure reliable performance and availability.
  3. Cloudflare is a popular choice for website hosting, as it offers a wide range of features, such as SSL support, DDoS protection and global CDN. It is easy to set up and user-friendly.
  4. DynDNS provides cloud DNS services to help customers manage their domain and subdomain configurations. It is easy to use, reliable and cost-effective.
  5. DNS Made Easy is a powerful DNS hosting provider with a wide range of features, including automated failover, real-time monitoring and analytics, and an easy-to-use control panel. It also offers advanced features for more experienced users.

 

Q27. What is the standard Time To Live (TTL) setting for entries made in Amazon Route 53?

Amazon Route 53 provides several default or recommended Time To Live (TTL) settings for each resource record set. These defaults are intended to help balance the need for latency and performance with the need to minimize the impact of changes made to your domain.

TTL is mandatory for each DNS record. So TTL is the length that a DNS record is cached on either the resolving server or the user’s own Laptop. The Lower the TTL, the faster changes to DNS records. Whenever you create a record set, you need to define TTL for it.

High TTL: (e.g. 24hr)

    Less traffic on DNS

    Possibly outdated records

Low TTL: (e.g 60 s)

    More traffic on DNS

    Records are outdated for less time

    Easy to change record

 

Q28. What’s the difference between a public hosted zone and a private hosted zone in Amazon Route 53?

A public hosted zone is a DNS zone that can be used by anyone on the internet, while a private hosted zone is a DNS zone that can only be used by a specific Amazon account.

 

Q29. Is it possible to route traffic based on user location using Amazon Route 53? If yes, then how?

Yes, it is possible to route traffic based on user location using Amazon Route 53. You can do this by creating a geo location resource record set. This will allow you to specify a location, such as a country or continent, and then route traffic to a specific resource, such as an Amazon S3 bucket or an Amazon EC2 instance, based on that location.

 

Q30. Does Amazon Route 53 offer redundancy options?

Yes, Amazon Route 53 offers a number of redundancy options to help keep your website or application up and running even if an Amazon data center goes offline. One option is to use Amazon Route 53’s Latency-Based Routing, which automatically routes traffic to the fastest data center. Another option is to use Amazon Route 53’s Geo DNS, which lets you route traffic to different data centers based on the geographic location of your users.

 

Q31. What is the default TTL setting for records created in Amazon Route 53?

The default TTL setting for records created in Amazon Route 53 is 1 hour.

 

Q32. Explain NS (Name Server) Record.

Name Server record type specifies the authoritative name servers responsible for managing DNS records for a domain.

Example: example.com. NS ns1.example.com. example.com. NS ns2.example.com.

 

Q33. What is a PTR record?

PTR (Pointer) Record is record type is used for reverse DNS lookups, mapping an IP address back to its associated domain name.

Example: 1.2.0.192.in-addr.arpa. PTR example.com.

 

Q34. What is the SRV record?

SRV (Service) Record: This record type specifies the location of services, such as LDAP, SIP, or XMPP, including the hostname, port, and priority.

Example: _sip._tcp.example.com. SRV 0 5 5060 sipserver.example.com.

 

Q35. What is the TXT record ?

TXT (Text) Record: This record type is used to store text-based information related to a domain, such as SPF (Sender Policy Framework) records, DKIM (DomainKeys Identified Mail), or DMARC (Domain-based Message Authentication, Reporting & Conformance) policies.

Example: example.com. TXT “v=spf1 ip4:192.0.2.0/24 -all”

 

Q36. What is a SOA record?

SOA (Start of Authority) Record: This record type contains administrative information about the zone, such as the primary name server, contact email, and various timing values for zone updates and expirations.

Example: example.com. SOA ns1.example.com. hostmaster.example.com. ( 2022031501 ; serial 10800 ; refresh 3600 ; retry 604800 ; expire 86400 ) ; minimum

 

Q37. What is the difference between an Alias record and a CNAME record in Route 53?

An Alias record is a Route 53-specific record that maps a domain name to another AWS resource without incurring additional latency. In contrast, a CNAME record maps a domain name to another domain name, which may result in an additional DNS lookup and increased latency.

 

Q38. How does Amazon Route 53 ensure high availability and reliability?

Route 53 uses a global network of DNS servers and leverages Anycast routing to direct user queries to the nearest DNS server. Additionally, Route 53 employs health checks to monitor resources and route traffic away from unhealthy instances.

 

Q39. Explain Route 53 Resolvers.

Route 53 Resolvers answers DNS queries for VPC domain names such as domain names for EC2 instances or ELB load balancers, and performs recursive lookups against public name servers for all other domain names.

DNS resolvers on your network can forward DNS queries to Resolver in a specified VPC. You can also configure Resolver to forward queries that it receives from EC2 instances in your VPCs to DNS resolvers on your network.

  • The Resolution is regional.
  • An inbound endpoint specifies the VPC that queries pass through on the way from your network to Resolver.
  • To forward DNS queries that originate on EC2 instances in one or more VPCs to your network, you create an outbound endpoint and one or more rules.
  • Route 53 Resolver DNS Firewall is a managed firewall that lets you block DNS queries made from known malicious domains and allow queries from trusted domains. This is achieved through the use of “blocklists” and “allowlists”.

 

Q40. What are Route 53 Health Checks types?

Types of health checks:

  1. HTTP and HTTPS health checks – Route 53 must be able to establish a TCP connection with the endpoint within four seconds. In addition, the endpoint must respond with an HTTP status code of 2xx or 3xx within two seconds after connecting.
  2. TCP health checks – Route 53 must be able to establish a TCP connection with the endpoint within ten seconds.
  3. HTTP and HTTPS health checks with string matching – Route 53 must be able to establish a TCP connection with the endpoint within four seconds, and the endpoint must respond with an HTTP status code of 2xx or 3xx within two seconds after connecting. After a Route 53 health checker receives the HTTP status code, it must receive the response body from the endpoint within the next two seconds.

 

Final Words

It is important to prepare yourself with the latest AWS EC2 interview questions while going for an AWS interview to crack it. 

It is really important to be up to date. We keep updating AWS EC2 interview questions if any new questions are being asked. Hope, we’ve covered most of the frequently asked AWS EC2 interview questions asked.

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