Tag Archives: Amazon Web Services

Route 53 in AWS

Route 53

A key networking element to AWS is the DNS service named Route 53. Remember, DNS is how we resolve IP addresses to domain names. For example – we access www.yahoo.com by typing that friendly name in a Web browser. Behind the scenes, DNS finds the correct IP address for this name. Think of DNS as a massive phone book. This phone book is distributed to servers all over the globe to ensure resolution can always occur. Hopefully.

It is no surprise that AWS offers a DNS service. After all, AWS has networks all over the world already. They also want to make sure they can provide DNS names to customers for their resources they build in the cloud.

Here are fun facts that you should know about Route 53:

  • It is completely compliant with IPv6
  • While Route 53 makes it easy to access resources inside of your AWS infrastructure, you could also use it to provide resolution for resources you have outside of their cloud
  • Route 53 is capable of DNS health checks so you can ensure traffic is sent to healthy nodes in your infrastructure
  • Amazon Route 53 Traffic Flow makes it easy for you to manage traffic globally through a variety of routing types, including Latency Based Routing, Geo DNS, Geoproximity, and Weighted Round Robin—all of which can be combined with DNS Failover in order to enable a variety of low-latency, fault-tolerant architectures
  • Route 53 also offers domain name registrations, so if you need a domain name for your organization, you do not have to shop beyond AWS for this service
  • Private DNS services are possible if you want to use the name resolution inside private VPC structures without advertising names to the public Internet
  • Route 53 supports redirection, so you can redirect traffic destined for one domain to another without explicitly impacting the clients
  • S3 Zone Apex support now exists – this makes it possible to permit access to your website using just the domain name – for example, http://abcompany.com

AWS Cloud Practitioner at CBT Nuggets

A Default VPC in AWS

VPC

Amazon tries to lower your barrier to entry when it comes to quickly making resources available via the cloud. As such, you are built a nice default VPC. This post walks you through what is created for you.

  • The default VPC itself – there is a unique ID associated with this for identification and a CIDR range (172.31.0.0/16)
  • Subnets – you get a subnet in each of your Availability Zones; these subnets are publicly reachable; they are /20 and feature 4091 available addresses
  • Route Table – there is a route table constructed for you; it directs 172.31.0.0/16 to stay local, and there is a default route (0.0.0.0/0) directing traffic to an Internet Gateway constructed for you
  • Internet Gateway – this allows your default VPC resources to reach the outside world
  • DHCP Options Set – there is an entry done for you which contains the domain name associated with your default VPC
  • Network ACL – there is a Network ACL associated with all three of your subnets; it is completely permissive by default; it allows all traffic inbound and all traffic outbound
  • Security Group – there is a default security group created for you; it is restrictive in nature in that it permits no traffic inbound

Note there are plenty of other VPC components available for your default VPC, but you would need to configure them. These components include:

  • Egress only Internet Gateways
  • Elastic IPs
  • Endpoints
  • Endpoint Services
  • NAT Gateways
  • Peering Connections
  • Customer Gateways
  • Virtual Private Gateways
  • VPN Connections

CCIERS