All about DNS - OCI DNS - Part 3

OCI DNS Part 3: Setting Up Listener and Forwarder

Welcome to the third part of our series on Oracle Cloud Infrastructure (OCI) DNS. In the previous parts, we covered the basics of DNS, creating a private zone, and associating it with a Virtual Cloud Network (VCN). In this part, we will focus on setting up a DNS Listener and Forwarder to manage DNS queries between your on-premises network and OCI.

Understanding DNS Listener and Forwarder

The DNS Listener and Forwarder setup in OCI allows you to route DNS queries between your on-premises network and OCI. This configuration helps in maintaining a unified DNS resolution strategy across hybrid environments, ensuring seamless connectivity and name resolution.

Components Involved

• DNS Listener: Listens for DNS queries from your on-premises network or other sources.
• DNS Forwarder: Forwards DNS queries to the appropriate DNS server (either in OCI or on-premises) based on the query type and domain.

Step-by-Step Guide to Set Up DNS Listener and Forwarder

1. Setting Up DNS Listener

1. Navigate to the DNS Management Console
   • Log in to your OCI account.
   • From the OCI console, go to the "Networking" section and select "DNS Management".
2. Create a DNS Listener
   • Click on the "Create Listener" button.
   • Fill in the necessary details:
     • Name: Enter a name for your DNS listener.
     • VCN: Select the VCN where the listener will be set up.
     • Subnet: Select the subnet for the listener.
   • Click "Create Listener".

2. Setting Up DNS Forwarder

1. Navigate to the DNS Management Console
   • In the DNS Management section, go to the "Forwarders" tab.
2. Create a DNS Forwarder
   • Click on the "Create Forwarder" button.
   • Fill in the necessary details:
     • Name: Enter a name for your DNS forwarder.
     • Target DNS Servers: Add the IP addresses of the target DNS servers (both on-premises and in OCI).
   • Click "Create Forwarder".

Illustrating the Traffic Flow

The following diagram illustrates how traffic is handled by the DNS Listener and Forwarder, showing the flow of DNS queries between on-premises and OCI environments.

Testing the Configuration

After setting up the DNS Listener and Forwarder, it's important to test the configuration to ensure that DNS queries are correctly routed.

Steps to Test the Configuration

1. Launch an Instance
   • Create or use an existing instance in the VCN associated with the DNS listener.
2. Configure DNS Resolver
   • Ensure the instance is configured to use the DNS listener for DNS resolution.
3. Perform DNS Queries
   • Use the nslookup or dig command to test DNS resolution.
   • Verify that DNS queries for domains hosted in OCI and on-premises are resolved correctly.

Conclusion

In this blog, we covered the steps to set up a DNS Listener and Forwarder in OCI, ensuring efficient DNS query management across on-premises and cloud environments. This setup helps maintain a consistent and unified DNS resolution strategy, enhancing the connectivity between hybrid infrastructures.

This ends our OCI DNS series....!!!