05 - Route53 Flashcards Preview

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Flashcards in 05 - Route53 Deck (9)
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1
Q

What is Route53?

A
  • Route 53 is Amazons DNS Service
  • Route 53 allows you to map your domain names to
    • EC2 Instances
    • Load Balancers
    • S3 Buckets
2
Q

Route 53 performs three main functions

A
  • Register domain names
  • Route internet traffic to the resources for your domain
  • Check the health of your resources
    • Route 53 sends automated requests over the internet to a resource, such as a web server, to verify that it’s reachable, available, and functional.
3
Q

Naked Domain & Zone Apex Records

A
  • Naked Domain Name (no host names) = penn-family2.org
  • Zone Apex Record = penn-family2.org
4
Q

Alias Records

A

Alias Record Details

  • Created by Amazon, very similar to CNAME (.e.g you can map one domain to another)
    • Alias records are used to map rescue record sets in your hosted zone to elastic load balancers, CloudFront distributions, or S3 buckets that are configured as websites
    • Key Difference - A CNAME cannot be used for naked domain names (zone apex records), it must either be an A Records or an Alias
  • Alias records automatically map your domain name to an Elastic Load Balancers
  • Alias resource record sets can save you time because Amazon Route53 automatically recognizes changes in the record sets that the alias resource record refers to
    • Example: example.com -> ELB (lb-1-1234.us-east1.elb.amazonaws.com)
    • If IP address of ELB changes, Route53 automatically provides the new address for example.com without any changes to the hosted zone that contains the resource record sets for example.com
  • Elastic Load Balancers only use domain names
  • Alias records are similar to CNAME records, but there are some important differences:
5
Q

CNAMEs vs. Alias Records

A

CNAMEs

  • Canonical Name = CNAME

Aliases

  • Alias records provide a Route 53–specific extension to DNS functionality.
  • Instead of an IP address or a domain name, an alias record contains a pointer to a:
    • CloudFront Distribution domain name: d111111abcdef8.cloudfront.net
    • Elastic Beanstalk Environment CNAME: example.elasticbeanstalk.com
    • Elastic Load balancer DNS Name: example-1.us-east-2.elb.amazonaws.com
      • Classic - ELB
      • Application - ALB
      • Network - NLB
    • S3 Website Endpoint: s3-website.us-east-2.amazonaws.com
    • Another Route53 record in the same zone (e.g. resource record set in this hosted zone): www.example.com
    • VPC endpoint: example.us-east-2.vpce.amazonaws.com
    • API Gateway custom regional API: d-abcde12345.execute-api.us-west-2.amazonaws.com
6
Q

IP Addresses

A

IP Addresses come in two forms: IPv4 & IPv6

  • IPv4 - 32 bits, supports 4 Billion Addresses
  • IPv6 - 128 bits, supports 340 undecillion addresses
    • AWS is fully compatible with IPv6
7
Q

What is contained in the Start of Authority Record?

A

What is contained in the Start of Authority Record?

  • Specifies authoritative information about the zone
  • The administrator of the zone
  • Name of the server that supplied data for the zone
  • How long for updates, failed zone transfers, default number for TTL on resource records, etc..
  • TTL additional information
  • The lower the TTL the faster updates to DNS records will be propagated throughout the network
8
Q

What are Name Server (NS) Records?

A

What are Name Server (NS) Records?

  • These records indicate which name servers are authoritative for the zone / domain.
  • The NS records are supplied to the domain register
  • The NS records tell the top-level domain how to route traffic to you
  • NS Records are primarily used if you want to break your domain into subdomains.
  • Subdomains indicate you are delegating a portion of a domain name to a different group of name servers
  • Thus creating NS records to point the name of the subdomain to different name servers.
9
Q

What is contained in a Resource Record Set?

A

What is contained in a Resource Record Set? - Background Material -

  • Used to route traffic to your resources
  • Each record set contains
    • Name - your domain name or your sub-domain name
    • Type - the type of resource you want traffic routed to (e.g. MX for email, A for IPv4 address, AAAA for IPv6 address)
    • Value - relates to type
      • MX = mail server name
      • A = IPv4 Address
      • AAAA = IPv6 Address