Using Route 53 private hosted zones

What is an Amazon Route 53 private hosted zone, and when would you use one instead of a public hosted zone?

An Amazon Route 53 private hosted zone is a container that holds information about how you want to route traffic for a domain and its subdomains within one or more Amazon Virtual Private Clouds (VPCs). You use a private hosted zone when you want to use Amazon’s Route 53 service to resolve domain names in a private network without exposing DNS information to the public Internet. Private hosted zones are typically used for internal network infrastructures where there is no need for the outside world to resolve the domain.

How do you associate a VPC with a private hosted zone in Amazon Route 53?

To associate a VPC with a private hosted zone in Amazon Route 53, you navigate to the Route 53 console, go to the Private Hosted Zone details, and click on “Associate VPC.” From there, you select the VPC and the region where it resides. After providing the necessary information, you save the changes, which will allow DNS queries from the specified VPC to be answered by the private hosted zone.

Can you resolve DNS names between VPCs using Route 53 private hosted zones, and if so, how?

Yes, you can resolve DNS names between VPCs using Route 53 private hosted zones. To enable this, you need to associate the private hosted zone with multiple VPCs. This is done by adding associations for each of the VPCs that you want to resolve names between. Once associated, instances in each VPC can resolve domain names using the private hosted zone.

What is a query logging configuration in the context of Route 53 private hosted zones, and why would you configure it?

A query logging configuration for Route 53 private hosted zones enables you to log all DNS queries made to the hosted zone. This is useful for auditing and diagnostic purposes, as it helps you track the requests being made internally within your VPCs and troubleshoot any DNS resolution issues.

Can you enable DNS resolution and DNS hostnames in your VPC for Route 53 to work with a private hosted zone, and why is it required?

Yes, you need to enable both DNS resolution and DNS hostnames in your VPC for Route 53 to work with a private hosted zone. It’s required because without these settings enabled, the instances in your VPC will not be able to resolve DNS names within your private hosted zone. Enabling these options allows the Amazon-provided DNS server in the VPC to resolve DNS queries using your private hosted zone.

How do you handle overlapping namespaces if you have duplicate domain names in your private hosted zones for different VPCs?

To handle overlapping namespaces with duplicate domain names in private hosted zones for different VPCs, you must ensure that the VPC that needs to resolve a particular domain is associated only with the corresponding private hosted zone containing the correct DNS records. Carefully managing these associations will allow Route 53 to resolve the domain names to the appropriate resources within the intended VPCs.

How do you configure health checks for resources within a private hosted zone?

To configure health checks for resources within a private hosted zone, you create health checks using the Amazon Route 53 console or API by specifying the IP addresses or domain names of the resources you want to check and setting the parameters you want to monitor (e.g., response time, HTTP status codes). These health checks can then be associated with DNS failover configurations to route traffic away from unhealthy resources.

Can you share an example of when you’d recommend implementing Route 53 Resolver over traditional DNS solutions for a private hosted zone?

One would recommend implementing Route 53 Resolver when there is a requirement for advanced DNS features such as query logging, DNS forwarding between VPCs, and cross-account DNS resolution. It provides better integration with AWS services, enhances security by keeping DNS data within the AWS environment, and simplifies the process of resolving DNS queries between AWS and on-premises resources.

How does Route 53 Resolver DNS Firewall enhance your private hosted zone’s security posture?

Route 53 Resolver DNS Firewall adds an additional layer of security to your private hosted zone by giving you the ability to filter and monitor DNS requests. You can create rulesets that allow or block DNS queries based on domain names or lists of domain names, which helps prevent DNS exfiltration and block domains associated with known malicious activity. This ensures that even within a private network, DNS queries are protected against unwanted traffic and threats.

When configured correctly, how does Route 53 ensure high availability for domains in a private hosted zone?

Route 53 ensures high availability for domains in a private hosted zone by providing a highly available and scalable DNS service with low-latency DNS resolution. By offering DNS failover options, health checks, and the ability to distribute load across multiple resources, Route 53 helps maintain domain availability even in the case of resource failure or high traffic.