To troubleshoot network or connectivity issues preventing your application from reaching the Amazon Bedrock endpoint, start by verifying basic network configuration and access controls. First, confirm that your application’s environment (e.g., EC2 instance, Lambda function, or on-premises server) has outbound internet access or a properly configured VPC endpoint for Bedrock. If your application runs in a private VPC without a NAT gateway, ensure a Bedrock VPC endpoint exists in the same region and that the subnet’s route tables direct traffic to it. Check security groups and network ACLs to ensure they allow outbound HTTPS (port 443) traffic to Bedrock’s public endpoints (e.g., bedrock-runtime.<region>.amazonaws.com) or the VPC endpoint. Use tools like telnet, nc, or curl to test connectivity to the Bedrock endpoint—a timeout suggests blocked traffic, while a connection refusal might indicate DNS or routing issues.
Next, verify IAM permissions and authentication. Ensure the AWS credentials used by your application (e.g., IAM role, access keys) include the bedrock:InvokeModel permission in their attached policy. Use the AWS CLI to test permissions directly—for example, run aws bedrock-runtime list-foundation-models --region <region> to confirm the role can interact with Bedrock. If using temporary credentials (e.g., via STS), ensure they haven’t expired. For applications in AWS services like Lambda or ECS, validate that the execution role’s trust policy allows the service to assume it. If you’re using a proxy or firewall, ensure it’s configured to pass AWS signature headers (like Authorization) unmodified, as altering these headers will break AWS’s request signing process.
Finally, diagnose DNS and endpoint-specific issues. Use nslookup or dig to confirm the Bedrock endpoint resolves to an IP address. If resolution fails, check for typos in the endpoint URL or VPC DNS settings (e.g., enableDnsHostnames and enableDnsSupport in the VPC). For hybrid or multi-cloud setups, verify that DNS queries aren’t being intercepted or redirected. If your application uses AWS SDKs, ensure they’re updated to a version supporting Bedrock and that the SDK’s configured region matches the endpoint’s region. Enable debug logging in the SDK (e.g., AWS SDK for Python (boto3) with boto3.set_stream_logger()) to capture detailed request/response data. If all else fails, check AWS Health Dashboard for regional service outages and review CloudTrail logs for API error codes (e.g., AccessDeniedException or ThrottlingException), which can pinpoint authorization or rate-limiting issues.