Lambda container with empty startup logs indicates network isolation

When Lambda execution environment times out with completely empty logs (only showing the lambda container ID header with no actual output), this indicates the Lambda runtime cannot reach LocalStack endpoints due to network misconfiguration, preventing initialization from completing.

Inspect the 'Logs from the execution environment' output in LocalStack debug logs. If logs show only the container ID with no error messages, verify: 1) Lambda container can resolve and reach LOCALSTACK_HOSTNAME, 2) DNS is correctly set to LocalStack IP, 3) Docker network configuration allows Lambda-to-LocalStack communication. Check docker network inspect output for the network both containers are on.