Configure DNS using custom DNS server

Follow these general steps to configure reverse DNS using a custom DNS server.

Step 1: Create a new VPC or use your existing VPC

You can create a new VPC from the Amazon VCP console (for example by using Start VPC Wizard):
- CIDR block example: 10.1.0.0/16
- Subnet’s CIDR example: 10.1.1.0/28
Make sure to:
- Enable DNS resolution for the VPC. You can do this by selecting the VPC, selecting Actions > Edit DNS resolution and choosing Yes.
- Enable DNS hostnames for the VPC. You can do this by selecting the VPC, selecting Actions > Edit DNS hostnames and choosing Yes.

	Note
	Optionally, you may want to set up an Internet Gateway for the VPC and add a default route to the routing table for the Internet Gateway. Additionally, you may want to enable the Auto-assign Public IP option. This way Cloudbreak would reach the cluster from outside of the VPC and the cluster would have internet access.

Step2: Set up DNS server in your VPC/subnet

In the configuration ensure that you have DNS records and reverse DNS pointers for all IP address (for example 10.3.3.4-14)

Example unbound configuration:

[root@ip-10-3-3-9 conf.d]# cat 00-cloudbreak.cloud.conf
   server:
      local-zone: "cloudbreak.cloud." static
      local-data: "aww1.cloudbreak.cloud. IN A 10.3.3.4"
      local-data-ptr: "10.3.3.4 aww1.cloudbreak.cloud."
      local-data: "aww2.cloudbreak.cloud. IN A 10.3.3.5"
      local-data-ptr: "10.3.3.5 aww2.cloudbreak.cloud."
      local-data: "aww3.cloudbreak.cloud. IN A 10.3.3.6"
      local-data-ptr: "10.3.3.6 aww3.cloudbreak.cloud."
      local-data: "aww4.cloudbreak.cloud. IN A 10.3.3.7"
      local-data-ptr: "10.3.3.7 aww4.cloudbreak.cloud."
      local-data: "aww5.cloudbreak.cloud. IN A 10.3.3.8"
      local-data-ptr: "10.3.3.8 aww5.cloudbreak.cloud."
      local-data: "aww6.cloudbreak.cloud. IN A 10.3.3.9"
      local-data-ptr: "10.3.3.9 aww6.cloudbreak.cloud."
      local-data: "aww7.cloudbreak.cloud. IN A 10.3.3.10"
      local-data-ptr: "10.3.3.10 aww7.cloudbreak.cloud."
      local-data: "aww8.cloudbreak.cloud. IN A 10.3.3.11"
      local-data-ptr: "10.3.3.11 aww8.cloudbreak.cloud."
      local-data: "aww9.cloudbreak.cloud. IN A 10.3.3.12"
      local-data-ptr: "10.3.3.12 aww9.cloudbreak.cloud."
      local-data: "aww10.cloudbreak.cloud. IN A 10.3.3.13"
      local-data-ptr: "10.3.3.13 aww10.cloudbreak.cloud."
      local-data: "aww11.cloudbreak.cloud. IN A 10.3.3.14"
      local-data-ptr: "10.3.3.14 aww11.cloudbreak.cloud."

Step 3: Create a DHCP options set

Perform this step from the Amazon VPC console. Select DHCP Options Sets from the left pane and click on Create a DHCP options set. Make sure to:

Set the Domain name to your preferred domain, for example cloudbreak.cloud
Set Domain name servers to the previously created DNS server
Optionally, set a Name tag

For detailed steps, refer to AWS documentation.

Step 4: Assign the newly created DHCP options set to your VPC

From the Amazon VPC console, select Your VPCs from the left pane.
Select the VPC created earlier.
Click on Actions > Edit DHCP Options Set.
Select the newly created DHCP option set.

Step 5: Create the cluster in the VPC configured in the preceding steps and you will have the same hostnames set as the domain names.

	Note
	Since you don’t have control the order over the IP addresses leased to the machines, the names may not be in order.