askvity

How Does Cloud DNS Work?

Published in Cloud Networking 4 mins read

Cloud DNS works by providing a highly scalable and resilient global network of DNS servers to translate domain names into IP addresses, effectively routing users to your online applications and services. Think of it as a phonebook for the internet.

Here's a breakdown of how it works:

  • You Provide DNS Records: You configure DNS records (e.g., A records, CNAME records, MX records) for your domain name within your cloud provider's DNS service. These records map your domain name (like example.com) to the IP addresses of your servers or other services.

  • Propagation to Authoritative Name Servers: When you create or update these records, the cloud DNS provider automatically distributes them to its network of authoritative name servers located around the globe.

  • Recursive DNS Servers Query Authoritative Name Servers: When a user types your domain name into their browser, their computer sends a DNS query to a recursive DNS server (often provided by their ISP or a public service like Google Public DNS or Cloudflare). If the recursive server doesn't have the answer cached, it starts querying authoritative name servers.

  • Authoritative Name Servers Respond: The recursive DNS server eventually queries one of the cloud DNS provider's authoritative name servers for your domain. That authoritative server responds with the IP address (or other relevant information) stored in your DNS records.

  • Recursive DNS Servers Cache the Response: The recursive DNS server caches the response from the authoritative name server for a specified period (the Time-To-Live, or TTL, value in your DNS record). This caching improves performance and reduces the load on the authoritative name servers.

  • User's Computer Connects: The recursive DNS server returns the IP address to the user's computer. The user's computer then uses that IP address to connect to your web server or application server.

Key Benefits of Using Cloud DNS:

  • Scalability: Cloud DNS services can handle a massive number of DNS queries without performance degradation.

  • Resilience: Geographically distributed name servers ensure high availability and protect against outages.

  • Performance: Global distribution and caching minimize latency and improve website loading times.

  • Cost-Effectiveness: Cloud DNS is often pay-as-you-go, eliminating the need to maintain your own DNS infrastructure.

  • Security: Cloud DNS providers offer DDoS protection and other security features to protect your DNS infrastructure from attacks.

Example Scenario:

  1. You want to host a website at www.example.com.
  2. You use Cloud DNS to create an A record for www.example.com pointing to the IP address of your web server (e.g., 192.0.2.1).
  3. A user in London types www.example.com into their browser.
  4. Their computer queries their ISP's DNS server.
  5. The ISP's DNS server queries one of the authoritative name servers for your domain, hosted by your cloud DNS provider.
  6. The authoritative name server responds with the IP address 192.0.2.1.
  7. The ISP's DNS server caches this response and sends it back to the user's computer.
  8. The user's computer connects to your web server at 192.0.2.1, and your website is displayed in their browser.

In essence, Cloud DNS simplifies the process of managing and distributing your domain's DNS information, ensuring reliable and performant access to your online resources. It handles the complexities of DNS infrastructure so you can focus on your application.

Related Articles