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Zorluk: OrtaVPC Connectivity and Routing Troubleshooting

A company has deployed Amazon EC2 instances in a private subnet of a VPC. The instances need to write data to Amazon Kinesis Data Streams. To prevent the data from traversing the public internet, a SysOps administrator creates an interface VPC endpoint for Kinesis Data Streams in the VPC and enables the private DNS option. However, the EC2 instances are still unable to connect to the Kinesis service using the default service name kinesis.us-east-1.amazonaws.com. Which of the following configuration changes will resolve this connectivity issue?

  1. A
    Add a route to the private subnet route table with the destination of the Kinesis service pointing to an Internet Gateway.
  2. B
    Associate the interface VPC endpoint with the route table of the private subnet.
  3. Enable DNS hostnames and DNS resolution attributes for the VPC.Cevap
  4. D
    Modify the private subnet network ACL outbound rules to allow all ephemeral ports to the Kinesis service range.

Cevap

Enable DNS hostnames and DNS resolution attributes for the VPC.
To resolve the hostnames of interface VPC endpoints using private DNS, the VPC must have both 'enableDnsHostnames' and 'enableDnsSupport' set to true. When these attributes are enabled, the public DNS hostname of the AWS service (such as kinesis.us-east-1.amazonaws.com) resolves to the private IP addresses of the endpoint network interfaces (ENIs) inside the VPC. Without these settings, the hostname resolves to public IP addresses, which are unreachable from a private subnet without internet access.

Adım Adım Çözüm

1
Check the DNS configuration attributes of the VPC.
Identify that the 'enableDnsHostnames' or 'enableDnsSupport' attributes are set to false.
Interface VPC endpoints require both DNS hostnames and DNS support to be enabled in order for private DNS hostnames to resolve correctly.
2
Enable 'enableDnsHostnames' and 'enableDnsSupport' in the VPC settings.
The public service hostname resolves to the private IP address of the endpoint's network interface (ENI).
Enabling these attributes allows the Route 53 Resolver to intercept the DNS queries and return the private endpoint IPs instead of public IPs.

Anahtar Kavram

Interface VPC Endpoints and Private DNS resolution requirements
Tahmini Süre:1m 30s
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