Route 53 Flashcards
What is Route 53?
is a managed highly available and scalable cloud Domain Name System (DNS) web service
Which are the most common records in AWS Route 53?
- A
- AAAA
- CNAME
- Alias
What is A Route 53 record?
hostname to IPv4
What is AAAA Route 53 record?
hostname to IPv6
What is CNAME Route 53 record?
hostname to hostname
What is Alias Route 53 record?
hostname to AWS resource
What domains can Route53 use?
- public domain names you own (or buy) application1.mypublicdomain.com
- private domain names that can be resolved by your instances in your VPCs. application1.company.internal
What are the main features of Route53?
- Load balancing
- Health checks
- Routing policy
How does Load Balancing work in Route53?
through DNS – also called client load balancing
How are Health Checks in Route53?
limited
What are the Routing Policies in Route53?
- simple
- failover
- geolocation
- latency
- weighted
- multi value
What is mandatory for each Route53 record?
TTL (Time to Live)
What is the impact of TTL on Route53?
impacts on traffic and the expiration of records (outdated or not)
What are the 2 main features that has Alias that CNAME does not have?
- works for root domain as well
- includes Native health check
What is Route53 Simple Routing Policy?
Maps a hostname to another hostname
When to use Route53 Simple Routing Policy?
Use when you need to redirect to a single resource
How does work Route53 Simple Routing Policy health checks?
You can’t attach health checks to simple routing policy
What if multiple values are returned in a Route53 Simple Routing Policy?
a random one is chosen by the client
What is Route53 Weighted Routing Policy?
Control the % of the requests that go to specific endpoint
What is helpful for Route53 Weighted Routing Policy?
Helpful to test 1% of traffic on new app version for example and to split traffic between 2 regions
Can Route53 Weighted Routing Policy be associated with health checks?
yes
What is Route53 Latency Routing Policy?
Redirect to the server that has the least latency close to us
When is helpful to use Route53 Latency Routing Policy?
Super helpful when latency of users is a priority
What is default number of health checks required for Route53 to determine the state?
3
What is Default Health Check Interval for Route53?
30s can be set to 10s at a higher cost
How many health checks are performed by Route53 the first time?
15, 1 request every 2 seconds on average
What kind of health checks perform Route53?
Can have HTTP, TCP and HTTPS health checks (no SSL verification)
What is possible to integrate to health checks in Route53?
CloudWatch
To what is possible to link health checks to in Route53?
To DNS queries
What is Route53 Failover Routing Policy?
lets you route traffic to a resource when the resource is healthy or to a different resource when the first resource is unhealthy
What is Route53 Geo Location Routing Policy?
Use when you want to route traffic based on the location of your users
What should you do when you use Route53 Geo Location Routing Policy?
create a “default” policy in case there is no match on location
What is Multi Value Geo Location Routing Policy?
Use when routing traffic to multiple resources and want to associate a Route 53 health checks with records
What is similar to a Multi Value Geo Location Routing Policy
to an ELB but is not a substitute
What is a Registrar?
A domain name registrar is an organization that manages the reservation of Internet domain names like GoDaddy, Google Domains, ROUTE53, etc…
What is not a Registrar?
a DNS (But each domain registrar usually comes with some DNS features)
What is 3rd party Registrar in AWS Route 53?
If you buy your domain on 3rd party website, you can still use Route53.
What do you need to create on Route53 for 3rd party registrar?
Need to create a hosted zone
What do you need to do on a 3rd party registrar to use Route53 name servers?
Update NS Records on 3rd party website
What means having a High Route 53 DNS Records TTL?
- Less traffic on DNS
* Possibly outdated records
What means having a Low Route 53 DNS Records TTL?
- More traffic on DNS
- Records are outdated for less time
- Easy to change records