from AWS doc, it states that the Amazon DNS Server would be the Base of your VPC network range plus two. I'm confused if this server is also the same AmazonProvidedDNS that you set in your dhcp option sets.

The Amazon DNS server does not reside within a specific subnet or Availability Zone in a VPC. It's located at the address 169.254.169.253 (and the reserved IP address at the base of the VPC IPv4 network range, plus two) and fd00:ec2::253. For example, the Amazon DNS Server on a 10.0.0.0/16 network is located at 10.0.0.2. For VPCs with multiple IPv4 CIDR blocks, the DNS server IP address is located in the primary CIDR block.

Is the "Amazon DNS server" and AmazonProvidedDNS the same?

For example if my VPC's base network range is 10.0.0.0 if I run a DNS query against 10.0.0.2, I'm querying against the AmazonProvidedDNS (aka Amazon DNS Server)?

CodePudding user response：

AmazonProvidedDNS is an option in the default DHCP option set. DHCP option sets are settings for your VPC where you can specify IP addresses for things such as domain name server, NTP server and NetBIOS server.

From the docs linked above:

Domain name servers: The DNS servers that will be used to resolve the IP address of the host. In the default option set, the only value is AmazonProvidedDNS. The string AmazonProvidedDNS maps to Amazon's DNS server.

Essentially this means, if you have the default DHCP options set used for your VPC and you are querying the network address 2 address (for example: 10.0.0.2), you will be querying the Amazon DNS servers.

If you have time, you could also watch this AWS re:Invent 2019: Deep dive on DNS in the hybrid cloud presentation about how DNS works inside an AWS VPC.