Route 53 Flashcards
What are the DNS Terminologies?
- Domain Registrar: Amazon Route 53, GoDaddy, …
- DNS Records: A, AAAA, CNAME, NS, …
- Zone File: contains DNS records
- Name Server: resolves DNS queries (Authoritative or Non-Authoritative)
- Top Level Domain (TLD): .com, .us, .in, .gov, .org, …
- Second Level Domain (SLD): amazon.com, google.com, …
How does DNS works?
local dns - root dns - tld dns - sld dns server
What is Amazon Route 53?
A highly available, scalable, fully managed and Authoritative DNS, also a Domain Registar.
Can Route53 check the health of resources?
yes it can
Whats the availabilty of R53?
100%
What are in a R53 Record?
- Domain/subdomain Name – e.g., example.com
- Record Type – e.g., A or AAAA
- Value – e.g., 12.34.56.78
- Routing Policy – how Route 53 responds to queries
- TTL – amount of time the record cached at DNS Resolvers
What are the R53 supported records?
- (must know) A / AAAA / CNAME / NS
- (advanced) CAA / DS / MX / NAPTR / PTR / SOA / TXT / SPF / SRV
What is an A record?
A – maps a hostname to IPv4
What is an AAAA record?
AAAA – maps a hostname to IPv6
What is an CNAME record?
- CNAME – maps a hostname to another hostname
- The target is a domain name which must have an A or AAAA record
- Can’t create a CNAME record for the top node of a DNS namespace (Zone
Apex) - Example: you can’t create for example.com, but you can create for
www.example.com
What is a NS record?
- NS – Name Servers for the Hosted Zone
Whate types of Hosted Zones are in R53?
- Public Hosted Zones – contains records that specify how to route
traffic on the Internet (public domain names)
application1.mypublicdomain.com - Private Hosted Zones – contain records that specify how you route
traffic within one or more VPCs (private domain names)
application1.company.internal
Do you have to pay for Hosted Zones
Yes, $0.5 per month per zone
What is TTL?
It stands for Time to live. Defines the cache time for a record.
* High ttl - less traffic, can be outdated
* Low ttl - more cost, easy to change record
Is TTL mandatory?
Yes it is except for Alias records.