Route 53 Flashcards

1
Q

What is DNS?

A

Domain Name System translates hostnames into the machine IP addresses

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

4 types of DNS Records Route 53 supports:

A

A, AAAA, CNAME, NS,

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What does the Zone File contain?

A

DNS records

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What does the Name Server do?

A

resolves DNS queries (Authoritative or Non-Authoritative)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are Top Level Domain (TLD)?

A

.com, .us, .in, .gov, .org,

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What are Second Level Domain (SLD)?

A

amazon.com, google.com

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are the parts of a standard URL address?

A

Protocol, Full Qualified Domain Name, Sub Domain, Second Level Domain, Top Level Domain, Root

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is Amazon Route 53?

A

A highly available, scalable, fully managed and Authoritative DNS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is Authoritative ?

A

The customer (you) can update the DNS records

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

The only AWS service which provides …… availability SLA(service level argement)

A

100%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are Records?

A

How you want to route traffic for a domain.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What does each record contain?

A
  • Domain/subdomain Name
  • Record Type
  • Routing Policy
  • TTL
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is a Routing Policy?

A

How Route 53 responds to queries

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

RecordTypes - A:

A

Maps a hostname to IPv4

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

RecordTypes - AAAA:

A

Maps a hostname to IPv6

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

RecordTypes - CNAME:

A

Maps a hostname to another hostname

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

CNAME rules:

A
  1. The target is a domain name which must have an A or AAAA record
  2. Can’t create a CNAME record for the top node of a DNS namespace (Zone Apex)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

RecordTypes - NS:

A

Name Servers for the Hosted Zone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What does NS do?

A

Control how traffic is routed for a domain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is a Hosted Zones?

A

A container for records that define how to route traffic to a domain and its subdomains

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Public Hosted Zones –

A

Contains records that specify how to route traffic on the Internet (public domain names)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Private Hosted Zones –

A

Contain records that specify how you route traffic within one or more VPCs (private domain names)

23
Q

Features of High TTL – e.g., 24 hr

A
  • Less traffic on Route 53
  • Possibly outdated records
24
Q

Features of Low TTL – e.g., 60 sec.

A
  • More traffic on Route 53 ($$)
  • Records are outdated for less time
  • Easy to change records
25
Q

Except for……. records, TTL is mandatory for each….. record

A

Alias, DNS

26
Q

What is an Alias record?

A

Points a hostname to an AWS Resource (app.mydomain.com => blabla.amazonaws.com)

27
Q

Alias rules:

A
  • Works for ROOT DOMAIN and NON ROOT DOMAIN (aka mydomain.com)
  • Free of charge
  • Native health check
28
Q

Record Types - Alias:

A

Maps a hostname to an AWS resource

29
Q

Features:
- An extension to DNS functionality
- Automatically recognizes changes in the resource’s IP addresses
- You can’t set the TTL

A

Alias record type

30
Q

…….. is always of type……… for AWS resources

A

Alias Record, A/AAAA(IPv4 / IPv6)

31
Q

Alias Record Targets

A
  • Elastic Load Balancers
  • CloudFront Distributions
  • API Gateway
  • Elastic Beanstalk environments
  • S3 Websites
  • VPC Interface Endpoints
  • Global Accelerator accelerator
  • Route 53 record in the same hosted zone
32
Q

What can you not set an Alias record for?

A

EC2 DNS name

33
Q

How does a “routing policy” work?

A
  • It’s not the same as Load balancer routing which routes the traffic
  • DNS does not route any traffic, it only responds to the DNS queries
34
Q

Route 53 Supports the following Routing Policies:

A
  • Simple
  • Weighted
  • Failover
  • Latency based
  • Geolocation
  • Multi-Value Answer
  • Geoproximity (using Route 53 Traffic Flow feature)
35
Q

Features of Routing Policies - Simple (5)

A
  • Typically, route traffic to a single resource
  • Can specify multiple values in the same record
  • If multiple values are returned, a random one is chosen by the client
  • When Alias enabled, specify only one AWS resource
  • Can’t be associated with Health Checke
36
Q

Features of Routing Policies - Weighted (5)

A
  • Control the % of the requests that go to each specific resource
    • Assign each record a relative weight:
      traffic (%) = Weight for a specific record / Sum of all the weights for all the records
    • Weights don’t need to sum up to 100
  • DNS records must have the same name and type
  • Can be associated with Health Checks
37
Q

Use cases for Weighted policy:

A
  • load balancing between regions
  • testing new application versions…
38
Q

Weighted policy - how do you stop sending traffic to a resource?

A

Assign a weight of 0 to a record to stop sending traffic to a resource

39
Q

Weighted policy - what happens if all records how a weight of 0?

A

If all records have weight of 0, then all records will be returned equally

40
Q

Features Routing Policy - Latency(3)

A
  • Redirect to the resource that has the least latency close to us
  • Super helpful when latency for users is a priority
  • Can be associated with Health Checks (has a failover capability)
41
Q

Latency policy - what is latency based on?

A

Latency is based on traffic between users and AWS Regions

42
Q

HTTP Health Checks are only for……. …………

A

public resources

43
Q

What do Health Checks provide?

A

Automated DNS Failover

44
Q

What are the 3 possible Health Checks?

A

1.Health checks that monitor an endpoint
2. Health checks that monitor other health checks
3.Health checks that monitor CloudWatch Alarms

45
Q

Health Checks are…… with …… metrics

A

integrated, Cloud Watch

46
Q

Health Checks pass only when the endpoint responds with…

A

The 2xx and 3xx status codes

47
Q

Health Checks can be setup to pass / fail based on the text in ….

A

The first 5120 bytes of the response

48
Q

Configure you ……. to allow incoming requests from Route 53 Health Checkers

A

router/firewall

49
Q

What is a Calculated Health Checks?

A

Combining the results of multiple Health Checks into a single Health Check

50
Q

Can monitor up to ….. Child Health Checks

A

256

51
Q

With Calculated Health Checks you can specify how many of the …

A

health checks need to pass to make the parent pass

52
Q

Where are Private Hosted Zones done?

A

Route 53 health checkers are outside the VPC

53
Q

Health Checks cannot access …

A

private endpoints (private VPC or on-premises resource)

54
Q
A