Networking Flashcards
(50 cards)
Route53 Record Types
- A - maps a hostname to IPv4
- AAAA - maps hostname to IPv6
- CNAME - maps a hostname to another hostname
- NS - Name Servers for the Hosted Zone (indicates which DNS server is authoritative for that domain)
Route53
CNAME vs Alias
- CNAME: Points a hostname to any other hostname (can’t be use with root domain)
- Alias: Points a hostname to an AWS resource (works with root domain) and is free of charge.
Route53
Alias Records Targets
- ELB
- CloudFront Distributions
- API Gateway
- Elastic Beanstalk
- S3 websites
- VPC Interface endpoints
- Global Accelerator
- Route53 record in the same hosted zone
Routing Policies
Simple
Route traffic to a single resource, can’t be associated with Health Checks. If a record has multiple values, a random one is chosen by the client.
Routing Policies
Weighted
Control de % of the requests that go to each resource. Can be associated with Health Checks.
Route Policy
Latency based
Redirect to the resource that has the least latency, based on traffic between users and AWS regions. Can be associated with Health Checks.
Routing Policies
Failover (Active-Passive)
You have a primary and secondary record for disaster recovery.
Routing Policies
Geolocation
Based on user location by continent, country or US state Can be associated with Health Checks.
Routing Policies
Geoproximity
Based on the geographical location of users and resources. Ability to shift more traffic to resources based on the defined bias.
Must use Route53 Traffic Flow
Route53 Traffic Flow
Visual editor to
* Manage complex routing trees
* Create and mantain records in complex configurations.
* Configurations can be saved as Traffic Flow Policies
Routing Policies
Multi-Value
Can be associated with Health Checks, returns up to 8 healthy records.
Routing Policies
IP-based Routing
You provide a list of CIDRs for your clients and the corresponding endpoints. Optimizes performance and reduces network costs.
Route 53
Hosted Zones
Container for records that define how to route traffic.
- Public: specify how to route traffic on the Internet
- Private: specify how to route traffic within one or more VPCs
DNS Security Extensions (DNSSEC)
Verifies DNS data integrity and origin. Works only with Public Hosted Zones.
Route53 Health Checks
- Health checks that monitor a public endpoint
- Health checks that monitor up to 256 other health checks (calculated health checks)
- Health checks that monitor CloudWatch alarms (efective for private resources)
Route53 Resolver
Answers DNS queries for:
1. Local domain names for EC2 instances
2. Records in Private Hosted Zones
3. Records in public Name Servers
Route 53
Resolver Endpoints for Hybrid DNS
Can be associated with one or move VPCs in the same region
* Inbound Endpoint forward external DNS queries of domain names, for AWS resources and records in Private Hosted Zones to Route 53 resolver.
* Outbound Endpoint Conditionally forwards DNS queries to other DNS resolvers.
AWS Global Accelerator
Provides static IP addresses that serve as single fixed entry points for your clients. You associate them to regional endpoints. Accept incoming traffic onto the AWS global network from the edge location that is closest to your users
With which resources does standard Global Accelerator works?
- Elastic IP
- EC2 instances
- ALB
- NLB
Continuously monitors the health of all endpoints
CloudFront vs Global Accelerator
CloudFront
* Improves performance for both cacheable content
* Dynamic content served at the edge
Global Accelerator
* Manage traffic globally to multiple regional applications
* Optimize API performance by reducing latency
* Use static IP addresses for application access
Network ACLs
Stateless firewall at the subnet level. Supports allow and deny rules
Security Groups
Stateful rules at the instance level. Only supports allow rules
VPC Peering
- Connect to VPC privately using AWS network.
- Is not transitive.
- Must update route tables in subnets, uses the longest prefix match.
VPC Peering
Edge to edge routing
Invalid configuration of VPC Peering. Not transitive with VPN, Direct Connect, IGW, NAT and VPC Endpoints.