TOP 50 Interview Questions on AWS Cloud Computing Services – Route 53

1. What is Amazon Route 53?

Amazon Route 53 provides a highly available and scalable Domain Name System (DNS), name registration, and health-checking web services. It is designed to offer developers and businesses a particularly reliable and price effective way to route end users to Internet applications by translating names like example.com into the numeric IP addresses, like 192.0.2.1, that computers use to attach to every other. DNS combines with health-checking services to route traffic to healthy endpoints or to independently monitor and/or alarm on endpoints. You can also purchase and manage domain names like example.com and automatically configure DNS settings for your domains. Route 53 effectively connects user requests to infrastructure running in AWS like Elastic Load Balancing load balancers, Amazon EC2 instances, or Amazon S3 buckets.

2. What am i able to do with Amazon Route 53?

With Amazon Route 53, you’ll create and manage your public DNS records. Like a phone book, Route 53 allows you to manage the IP addresses listed for your domain names within the Internet’s DNS phone book. It also answers requests to translate specific domain names like into their corresponding IP addresses like 192.0.2.1. You can use Route 53 to make DNS records for a replacement domain or transfer DNS records for an existing domain. The simple, standards-based REST API for Route 53 allows you to simply create, update and manage DNS records. Route 53 additionally offers health checks to watch the health and performance of your application also as your web servers and other resources. 

3. What are the DNS server names for the Amazon Route 53 service?

Each Amazon Route 53 hosted zone is served by its own set of virtual DNS servers, to provide you with a highly available service. The DNS server names for every hosted zone are thus assigned by the system when that hosted zone is made .

4. What is a Domain Name System (DNS) Service?

It translates human readable names like www.example.com into the numeric IP addresses like 192.0.2.1 that computers use to attach to every other. The Internet’s DNS system works very similar to a phone book by managing the mapping between names and numbers. For DNS, the names are domain names (www.example.com) that are easy for people to remember and the numbers are IP addresses (192.0.2.1) that specify the location of computers on the Internet. DNS servers translate requests for names into IP addresses, controlling which server an user will reach once they name into their browser . These requests are called “queries.”

5. What is the difference between a Domain and a Hosted Zone?

A domain is a general DNS concept. It has easy recognizable names for numerically addressed Internet resources. For example, amazon.com is a domain. A hosted zone is a concept of Amazon Route 53. A hosted zone is analogous to a standard DNS zone file; it represents a set of records which will be managed together, belonging to one parent name . All resource record sets within a hosted zone must have the hosted zone’s name as a suffix. For example, the amazon.com hosted zone may contain records named www.amazon.com, and www.aws.amazon.com, but not a record named www.amazon.ca. You can use the Route 53 Management Console or API to make , inspect, modify, and delete hosted zones. 

6. What is the price of Amazon Route 53?

Amazon Route 53 charges are supported by actual usage of the service for Hosted Zones, Queries, Health Checks, and Domain Names.

You pay only for what you use. There are not any minimum fees, no minimum usage commitments, and no overage charges. Using the AWS Pricing Calculator you can estimate your monthly bills.

7. What types of access controls can I set for the management of my Domains on Amazon Route 53?

By using the AWS Identity and Access Management (IAM) service you can control management access to your Amazon Route 53 hosted zone. AWS IAM allows you to regulate who in your organization can make changes to your DNS records by creating multiple users and managing the permissions for every of those users within your AWS Account.

8. Does Amazon Route 53 offer a Service Level Agreement (SLA)?

Yes. It provides for a service credit if a customer’s monthly uptime percentage is below our service commitment in any billing cycle.

9. Does Amazon Route 53 provide query logging capability?

You can configure Amazon Route 53 to log information about the queries that Amazon Route 53 receives including domain name, location, date-time stamp, query type, etc. Amazon Route 53 starts to send logs to CloudWatch Logs, When you configure query logging. To access the query logs use CloudWatch Logs tools .

10. Does Amazon Route 53 use an anycast network?

Yes. Anycast may be a networking and routing technology that helps your end users’ DNS queries get answered from the optimal Route 53 location given network conditions. Users get improved performance and  high availability with Route 53.

11. Is there a limit to the number of hosted zones I can manage using Amazon Route 53?

Each Amazon Route 53 account is restricted to a maximum of 500 hosted zones and 10,000 resource record sets per hosted zone. Complete our request for a better limit and that we will answer your request within two business days.

12. How can I import a zone into Route 53?

Route 53 supports importing standard DNS zone files which may be exported from many DNS providers also as standard DNS server software like BIND. For newly-created hosted zones, also as existing hosted zones that are empty apart from the default NS and SOA records, you’ll paste your zone file directly into the Route 53, and Route 53 console automatically creates the records in your hosted zone. To get started with zone file import, read our walkthrough within the Amazon Route 53 Developer Guide.

13. Can I create multiple hosted zones for the same domain name?

Yes. Creating multiple hosted zones allows us to verify DNS settings during “test” environment, then replicate those settings on a hosted zone “production”. For example, hosted zone Z1234 could be your test version of example.com, hosted on name servers ns-1, ns-2, ns-3, and ns-4. Similarly, hosted zone Z5678 could be your production version of example.com, hosted on ns-5, ns-6, ns-7, and ns-8. Since each hosted zone features a virtual set of name servers related to that zone, Route 53 will answer DNS queries for instance .com differently counting on which name server you send the DNS query to.

14. Does Amazon Route 53 also provide website hosting?

No. Amazon Route 53 is an authoritative DNS service and doesn’t provide website hosting. However, you’ll use Amazon Simple Storage Service (Amazon S3) to host a static website. To host a dynamic website or other web applications, you can use Amazon Elastic Compute Cloud (Amazon EC2), which provides flexibility, control, and significant cost savings over traditional web hosting solutions.

15. Which DNS record types does Amazon Route 53 support?

Amazon Route 53 currently supports the subsequent DNS record types:

A (address record)

AAAA (IPv6 address record)

CNAME (canonical name record)

CAA (certification authority authorization)

MX (mail exchange record)

NAPTR (name authority pointer record)

NS (name server record)

PTR (pointer record)

SOA (start of authority record)

SPF (sender policy framework)

SRV (service locator)

TXT (text record)

16. Does Amazon Route 53 support DNSSEC?

Amazon Route 53 doesn’t support DNSSEC for DNS at this point . DNSSEC on domain registration was allowed by Amazon Route 53.

17. Does Amazon Route 53 support IPv6?

Yes. It supports both forward and reverse IPv6 records. The Amazon Route 53 service itself is additionally available over IPv6. Recursive DNS resolvers on IPv6 networks can use either IPv4 or IPv6 transport so as to submit DNS queries to Amazon Route 53. Using the IPv6 protocol Amazon Route 53 health checks also support monitoring of endpoints.

18. Does Amazon Route 53 support Weighted Round Robin (WRR)?

Yes. Weighted Round Robin allows you to assign weights to resource record sets so as to specify the frequency with which different responses are served. You may want to use this capability to try to do A/B testing, sending a little portion of traffic to a server on which you’ve made a software change. For instance, suppose you’ve got two record sets related to one DNS name—one with weight 3 and one with weight 1. Weights can be any number between 0 and 255.

19. What is Amazon Route 53’s Latency Based Routing (LBR) feature?

LBR (Latency Based Routing) may be a new feature for Amazon Route 53 that helps you improve your application’s performance for a worldwide audience. You can run applications in multiple AWS regions and Amazon Route 53, using dozens of edge locations worldwide, will route end users to the AWS region that gives the lowest latency.

20. How do I get started using Amazon Route 53’s Latency Based Routing (LBR) feature?

You can start using Amazon Route 53’s new LBR feature quickly and simply by using either the AWS Management Console or an easy API. You simply create a record set that has the IP addresses or ELB names of varied AWS endpoints and mark that record set as an LBR-enabled Record Set. Amazon Route 53 takes care of the remainder – determining the simplest endpoint for every request and routing end users accordingly, very similar to Amazon CloudFront, Amazon’s global content delivery service, does.

21. What is Amazon Route 53’s Geo DNS feature?

It allows you to balance load by directing requests to specific endpoints supporting the geographic location from which the request originates. It may make it possible to customize localized content, within the right language or restricting distribution of content to only the markets you’ve licensed, like presenting detail pages. It also allows you to balance load across endpoints during a predictable, easy-to-manage way, ensuring that every end-user location is consistently routed to an equivalent endpoint. Geo DNS provides three geographic granularity: country, continent, and state, and Geo DNS also provides a worldwide record which is served in cases where an end user’s location doesn’t match any of the precise Geo DNS records you’ve got created. You can also combine Geo DNS with other routing types, like Latency Based Routing and DNS Failover, to enable a spread of low-latency and fault-tolerant architectures.

22. How do I get started using Amazon Route 53’s Geo DNS feature?

You can start using Amazon Route 53’s Geo DNS feature quickly and simply by using either the AWS Management Console or the Route 53 API. You simply create a record set and specify the applicable values for that sort of record set, mark that record set as a Geo DNS-enabled Record Set, and choose the geographical area (global, continent, country, or state) that you simply want the record to use. You can learn more about the way to use Geo DNS within the Amazon Route 53 Developer Guide.

23. Explain difference between Geo DNS and Latency Based Routing?

Geo DNS based routing decisions on the geographic location of the requests. In some cases, geography may be a good proxy for latency; but there are certainly situations where it’s not. LatencyBased Routing utilizes latency measurements between viewer networks and AWS data centers. These measurements are wont to determine which endpoint to direct users toward.

If your goal is to attenuate end-user latency, we recommend using Latency Based Routing.  we recommend using Geo DNS, If you’ve got localization requirements, compliance, or other use cases that need stable routing from a selected geography to a selected endpoint.

24. Does Amazon Route 53 support multiple values in response to DNS queries?

Route 53 now supports multiple answers in response to DNS queries. While not a substitute for a load balancer, the power to return multiple health-checkable IP addresses in response to DNS queries may be a thanks to using DNS to enhance availability and load balancing. you’ll create one multivalue answer record for every resource and optionally, associate an Amazon Route 53 health check with each record, If you would like to route traffic randomly to multiple resources, like web servers. Amazon Route 53 supports up to eight healthy records in response to every DNS query.

25. What is Amazon Route 53 Traffic Flow?

It is an easy-to-use and cost-effective global traffic management service. With It, you’ll improve the performance and availability of your application for your end users by running multiple endpoints around the world, using Amazon Route 53 Traffic Flow to attach your users to the simplest endpoint supported latency, geography, and endpoint health. Amazon Route 53 Traffic Flow makes it easy for developers to make policies that route traffic supported the constraints they care most about, endpoint health, geo proximity, including latency, load, and geography. Customers can customize these templates or build policies from scratch employing a simple visual policy builder within the AWS Management Console.

26. What are the advanced query types supported in Amazon Route 53 Traffic Flow?

It supports all Amazon Route 53 DNS Routing policies including endpoint health, latency, multivalue; weighted round robin, answers, and geo. In addition to these, Traffic Flow also supports geo proximity based routing with traffic biasing.

27. What are the advanced query types supported in Amazon Route 53 Traffic Flow?

It supports all Amazon Route 53 DNS Routing policies including latency, endpoint health, multivalue; answers, weighted round robin, and geo. In addition to these, Traffic Flow also supports geo proximity based routing with traffic biasing.

28. Do Route 53 health checks follow HTTP redirects?

No. Route 53 health checks consider an HTTP 3xx code to be a successful response, in order that they don’t follow the redirect. The checkup searches for the required string within the body of the redirect. Because the checkup doesn’t follow the redirect, it never sends an invitation to the situation that the redirect points to and never gets a response from that location. For string matching health checks, we recommend that you simply avoid pointing the checkup at a location that returns an HTTP redirect.

29. What is the sequence of events when failover happens?

In simplest terms, the subsequent events will happen if a checkup fails and failover occurs:

Route 53 conducts a checkup of your application. In this example, your application fails three consecutive health checks, triggering the subsequent events.

Route 53 disables the resource records for the failed endpoint and does not serve these records. This is the failover step, which causes traffic to start being routed to your healthy endpoint(s) rather than your failed endpoint.

30. Can I register domain names with Amazon Route 53?

Yes. you’ll use the AWS Management Console or API to register new domain names with Route 53. You may also request to transfer in existing domain names from other registrars to be managed by Route 53. Domain name registration services are provided under our name Registration Agreement.

31. What Top Level Domains (“TLDs”) do you offer?

Route 53 offers a good selection of both generic Top Level Domains (“gTLDs”: for instance , .com and .net) and country-code Top Level Domains (“ccTLDs”: for instance , .de and .fr).

32. How can I register a domain name with Route 53?

Log into your account and click on “Domains”, to get started. Then, click the large blue “Register Domain” button and complete the registration process.

33. How long does it take to register a domain name?

Depending on the TLD you’ve selected, registration can take from a couple of minutes to many hours. Once the domain is successfully registered, it’ll show up in your account.

34. What information do I need to provide to register a domain name?

In order to register a website name, you would like to supply contact information for the registrant of the domain, including name, address, telephone number , and email address. If the executive and technical contacts are different, you would like to supply that contact information, too.

35. Why do I need to provide personal information to register a domain?

ICANN, the administration for domain registration, requires that registrars provide contact information, including name, address, and telephone number , for each name registration, which registrars make this information publicly available via a Whois database. That you simply register as a private for domain names, Route 53 provides privacy protection, which hides your personal telephone number , email address, and physical address, free of charge.

36. Does Route 53 offer privacy protection for domain names I have registered?

Yes, It provides privacy protection at no additional charge. The privacy protection hides your phone number, email address, and physical address. Your first and surname are going to be hidden if the TLD registry and registrar allow it. When you enable privacy protection, a Whois query for the domain will contain the registrar’s address in situ of your physical address, and therefore the registrar’s name in situ of your name (if allowed). Your email address will be a registrar-generated forwarding email address that third parties may use if they wish to contact you. 

37. How do I transfer my domain name to Route 53?

Log into your account and click on “Domains”, to get started . Then, click the “Transfer Domain” button at the highest of the screen and complete the transfer process. Please confirm before you begin the transfer process, (1) your name is unlocked at your current registrar, (2) you’ve got disabled privacy protection on your name (if applicable), and (3) that you have obtained the valid Authorization Code from your current registrar which you will need to enter as part of the transfer process.

38. How do I check on the status of my transfer request?

You can view the status of name transfers within the “Alerts” section on the homepage of the Route 53 console.

39. Does Amazon Route 53 DNS support DNSSEC?

Amazon Route 53’s DNS services do NOT support DNSSEC at this time. However, our domain name registration service supports configuration of signed DNSSEC keys for domains when DNS service is configured at another provider.

40. What is Amazon Route 53 Resolver?

Route 53 Resolver is a regional DNS service that provides recursive DNS lookups for names hosted in EC2 as well as public names on the internet. This functionality is out there by default in every Amazon Virtual Private Cloud (VPC). For hybrid cloud scenarios you can configure conditional forwarding rules and DNS endpoints to enable DNS resolution across AWS Direct Connect and AWS Managed VPN.

41. Does regional support for Route 53 Resolver mean that all of Amazon Route 53 is now regional?

No. Amazon Route 53 public and private DNS, traffic flow, health checks, and domain name registration are all global services.

42. How can I measure the performance of my application’s endpoints using Amazon Route 53?

Health checks of Route 53 include an optional latency measurement feature which provides data on how long it takes your endpoint to reply to an invitation . When you enable the latency measurement feature, the Amazon Route 53 checkup will generate additional Amazon CloudWatch metrics showing the time required for Amazon Route 53’s health checkers to establish a connection and to start receiving data. Amazon Route 53 provides a separate set of latency metrics for every AWS region where Amazon Route 53 health checks are conducted.

43. What happens if all of my endpoints are unhealthy?

Route 53 can only fail over to an endpoint that’s healthy. If there are not any healthy endpoints remaining during a resource record set, Route 53 will behave as if all health checks are passing.

44. Can I configure a health check on a site accessible only via HTTPS?

Yes. It supports health checks over HTTPS, HTTP or TCP.

45. How can I use health checks to verify that my web server is returning the correct content?

You can use Route 53 health checks to see for the presence of a delegated string during a server response by selecting the “Enable String Matching” option. This option can be used to check a web server to verify that the HTML it serves contains an expected string. Or, you’ll create a fanatical status page and use it to see the health of the server from an indoor or operational perspective.

46. How do I see the status of a health check that I’ve created?

You can view the present status of a checkup , also as details on why it’s failed, within the Amazon Route 53 console and via the Route 53 API.

Additionally, each health check’s results are published as Amazon CloudWatch metrics showing the optionally, and endpoint’s health, the latency of the endpoint’s response. You can view a graph of the Amazon CloudWatch metric within the health checks tab of the Amazon Route 53 console to ascertain the present and historical status of the health check. You can also create Amazon CloudWatch alarms on the metric in order to send notifications if the status of the health check changes.

The Amazon CloudWatch metrics for all of your Amazon Route 53 health checks are also visible in the Amazon CloudWatch console. Each Amazon CloudWatch metric contains the Health Check ID (for example, 01beb6a3-e1c2-4a2b-a0b7-7031e9060a6a) which you can use to identify which health check the metric is tracking.

47. One of my endpoints is outside AWS. Can I find out DNS Failover on this endpoint?

Yes. a bit like you’ll create a Route 53 resource record that points to an address outside AWS, you’ll find out health checks for parts of your application running outside AWS, and you’ll fail over to any endpoint that you simply choose, no matter location. 

48. How many consecutive health check observations does an endpoint need to fail to be considered “failed”?

The default may be a threshold of three checkup observations: when an endpoint has failed three consecutive observations, Route 53 will consider it failed. However, On the endpoint Route 53 will still perform checkup observations and can resume sending traffic thereto once it passes three consecutive observations. This threshold value can change to any value between 1 and 10 observations.

49. What is DNS Failover?

DNS Failover consists of two components: health checks and failover. Health checks are automated requests sent over the web to your application to verify that your application is reachable, available, and functional. You can configure the health checks to be almost like the standard requests made by your users, like requesting an internet page from a selected URL. With DNS failover, Route 53 only returns answers for resources that are healthy and reachable from the surface world, in order that your end users are routed faraway from a failed or unhealthy part of your application.

50. Can I use the same private Route 53 hosted zone for multiple VPCs?

Yes, you’ll associate multiple VPCs with one hosted zone.