Dns not updating from dhcp
Amazon EC2 instances need IP addresses to communicate.Public IP addresses enable communication over the Internet, while private IP addresses enable communication within the network of the instance (either EC2-Classic or a VPC).
A DNS hostname is a name that uniquely and absolutely names a computer; it's composed of a host name and a domain name.If you enable DNS hostnames and DNS support in a VPC that didn't previously support them, an instance that you already launched into that VPC gets a public DNS hostname if it has a public IP address or an Elastic IP address.For information about DNS support for private hosted zones, see Using Private Hosted Zones.If you want to access the resources in your VPC using custom DNS domain names, such as example.com, instead of using private IP addresses or AWS-provided private DNS hostnames, you can create a private hosted zone in Amazon Route 53.When you launch an instance into a VPC, we provide the instance with a public DNS hostname only if DNS hostnames are enabled for the VPC.By default, DNS hostnames are enabled only for default VPCs and VPCs that you create using the VPC wizard in the VPC console.
We support the following VPC attributes to control DNS support.
Be sure to set both attributes to , queries to the Amazon provided DNS server at the 169.254.169.253 IP address, or the reserved IP address at the base of the VPC network range plus two will succeed. The Amazon DNS server cannot resolve private DNS hostnames if your VPC's IP address range falls outside of the private IP addresses ranges specified by RFC 1918.
DNS servers resolve DNS hostnames to their corresponding IP addresses. To use your own DNS server, update the DHCP options set for your VPC. To enable an EC2 instance to be publicly accessible, it must have a public IP address, a DNS hostname, and DNS resolution.
When you launch an instance into the EC2-Classic platform or into a default VPC, we provide the instance with public and private DNS hostnames.
Instances that you launch into a nondefault VPC might have public and private DNS hostnames, depending on the settings you specify for the VPC and for the instance.
You can view the DNS hostnames for a running instance or a network interface using the Amazon EC2 console or the command line.