Integration of On-Premises Network with AWS Cloud.
In today’s interconnected world, businesses often seek efficient ways to optimize their infrastructure and improve connectivity between on-premises resources and cloud services. One such approach involves utilizing a Microsoft DNS server located in the AWS cloud to facilitate DNS resolution for on-premises hosts. This blog post will explore the setup and benefits of this topology, focusing on a scenario where an on-premises web server is accessed through DNS resolution via a Microsoft DNS server on AWS. Let’s dive in!
Understanding the Topology:
The topology comprises an on-premises host, a Microsoft DNS server hosted on AWS, and a web server residing within the on-premises network. The following are the key network parameters involved:
On-Premises Host:
IP Address: 192.168.163.154
Gateway: 192.168.163.2
Microsoft DNS Server (AWS Cloud):
IP Address: 3.84.124.30
On-Premises Web Server:
IP Address: 192.168.163.200
Setting Up the Microsoft DNS Server on AWS: To enable DNS resolution for the on-premises host, you need to set up a Microsoft DNS server within an AWS EC2 instance. Here’s a step-by-step process to achieve this:
- Launch an EC2 instance in AWS and install the Microsoft DNS server software.
- Set up the necessary firewall rules to allow DNS traffic (port 53) between the on-premises network and the AWS cloud.
- Ensure that the DNS server has proper connectivity and can communicate with both the on-premises host and the web server.
Configuring the On-Premises Host: To utilize the Microsoft DNS server for DNS resolution, you need to configure the DNS settings on the on-premises host. Follow these steps:
- Access the network settings on the on-premises host and navigate to the DNS configuration.
- Set the primary DNS server to the IP address of the Microsoft DNS server hosted in AWS (3.84.124.30).
- Optionally, you can add a secondary DNS server for redundancy or fallback purposes.
- Save the settings and ensure that the on-premises host can communicate with the DNS server.
To configure a new A host in DNS with a primary zone as “mydns.com” and a host name as “mycisco” with an FQDN as “mycisco.mydns.com,” follow these steps:
Access the DNS management interface:
- Log in to the server hosting the DNS server software.
- Open the DNS management tool, such as the Microsoft DNS Manager.
Create a new primary zone:
- Right-click on the DNS server name in the DNS management tool.
- Select “New Zone” from the context menu.
- Follow the wizard to create a new primary zone with the domain name “mydns.com.”
Create a new A record for the host:
- Navigate to the newly created “mydns.com” zone.
- Right-click on the zone and select “New Host (A or AAAA).”
- Enter “mycisco” as the host name.
- Enter the IP address associated with the “mycisco” host.
- Click “Add Host” to create the A record.
Verify the FQDN:
- The FQDN for the host “mycisco” should automatically be set as “mycisco.mydns.com” since it is within the “mydns.com” zone.
Save and apply changes:
- Save the changes made to the DNS configuration.
Test the DNS resolution:
- On a client machine or the on-premises host, open a command prompt or terminal.
- Use the “nslookup” command followed by the host name to test DNS resolution. Example: nslookup mycisco.mydns.com
- Verify that the DNS resolution returns the correct IP address associated with the “mycisco” host
DNS Resolution Flow: With the setup in place, let’s understand how DNS resolution takes place:
- When the on-premises host attempts to connect to the web server using its hostname or fully qualified domain name (FQDN), the DNS resolution process begins.
- The on-premises host sends a DNS query to the configured Microsoft DNS server (3.84.124.30) in the AWS cloud.
- The Microsoft DNS server receives the query and checks its DNS records for the requested hostname or FQDN.
- If a matching record is found, the Microsoft DNS server responds to the on-premises host with the IP address of the web server (192.168.163.200).
- The on-premises host then establishes a connection to the web server using the provided IP address.
- Subsequent communication between the on-premises host and the web server takes place directly, without involving the Microsoft DNS server.
Why launching a DNS server in the cloud, such as AWS, is beneficial, presented in bullet points:
- Scalability and Elasticity: Cloud platforms allow you to scale resources based on demand, enabling you to adjust the capacity of the DNS server to handle varying traffic loads effectively.
- Redundancy and High Availability: Cloud providers offer redundant infrastructure to minimize downtime in case of failures, ensuring reliable DNS resolution for on-premises hosts.
- Global DNS Infrastructure: Cloud platforms have a global network of DNS servers, reducing latency by resolving DNS queries from nearby servers and improving performance for users worldwide.
- Security and Compliance: Cloud providers implement robust security measures, protecting your DNS infrastructure and data through encryption, compliance frameworks, and industry best practices.
- Simplified Management and Maintenance: Cloud-based DNS servers provide intuitive management interfaces and APIs, making it easier to configure DNS settings, manage DNS records, and monitor DNS traffic.
- Cost Optimization: Cloud platforms offer flexible pricing models, allowing you to align expenses with traffic patterns, optimize costs, and benefit from cost optimization tools and features.
In summary, launching a DNS server in the cloud brings scalability, high availability, global reach, enhanced security, simplified management, and cost optimization advantages. These benefits make cloud-based DNS servers an attractive option for businesses seeking to optimize their DNS infrastructure and improve connectivity between on-premises resources and cloud services.