DhcpOptions

Source: src/AWS/EC2/DhcpOptions.ts

A DHCP options set configures the DHCP parameters (domain name, DNS servers, NTP servers, NetBIOS settings) that a VPC hands out to the instances launched inside it. Attach a custom set to a VPC to override the AWS defaults — for example to point instances at your own DNS or an internal search domain.

A DHCP options set is immutable: AWS provides no edit API, so changing any DHCP parameter replaces the set. Setting vpcId associates the set with a VPC; clearing it (or deleting the resource) re-associates the VPC with the account’s default options set, since a set must be disassociated from every VPC before it can be deleted.

Creating a DHCP Options Set

Custom DNS and Search Domain

const dhcp = yield* AWS.EC2.DhcpOptions("CorpDhcp", {
  domainName: "corp.internal",
  domainNameServers: ["10.0.0.2", "AmazonProvidedDNS"],
  vpcId: myVpc.vpcId,
});

Creates the options set and associates it with the VPC in one step. Instances launched into the VPC receive the corp.internal search domain and the listed DNS servers.

NTP and NetBIOS Configuration

const dhcp = yield* AWS.EC2.DhcpOptions("Dhcp", {
  ntpServers: ["169.254.169.123"],
  netbiosNameServers: ["10.0.0.5"],
  netbiosNodeType: "2",
});

Creates an unassociated options set that you can associate later by setting vpcId.