AWS - Networking Flashcards
What is DNS?
DNS - Domain Name System
It is a system wich goal is to translate domain names that are understandable by humans (eg.: fb.com) to IP addresses that are assigned to computers and other devices in the Internet Network, eg.: 195.149.224.42,
How DNS works?
The whole process can be pictured in the following way:
1) User enters in the browser address eg.: fb.com
2) System sends a query to known to him DNS server with the ask to reply with IP address for fb.com
3) DNS system responds to the IP address that is assigned to fb.com
4) User’s computer connects with IP address returned by the DNS system.
What is a DNS record?
DNS record defines how you want to route traffic for the domain or a subdomain. For example. you might create records for example.com and www.example.com that route traffic to a web server that has an IP address of 192.0.2.234
WHat is an “A” type record and its usage?
Maps a domain or subdomain to an IP address e.g.: It maps www.whizlabs.com to 69.11.66.143
The main use of A record is for IP address lookup. Using an A record, a web browser is able to load a website using the domain name. As a result, we can access websites on the internet without knowing their IP addresses.
What is a CNAME (Canonical Name) Record and its usage?
Points a domain or subdomain name to another domain or subdomain name in the DNS: E.g: It maps pictures.whizlabs.com to images.whizlabs-internal.com
What is an “Alias record”?
A type of record that you can create with Amazon Route 53 to route traffic to AWS resources such as Amazon CloudFront distributions and Amazon S3 bucket.
What is a “SRV” DNS record?
The DNS “service” (SRV) record specifies a host and port for specific services such as voice over IP (VoIP), instant messaging, and so on. Most other DNS records only specify a server or an IP address, but SRV records include a port at that IP address as well.
