VPC-attached Lambda functions need network interfaces and subnet IP addresses to scale. When a small subnet is shared with other workloads, a burst of concurrent invocations can exhaust available addresses, and the function fails before your code ever runs — which is why the application logs show nothing.
During market-open bursts, a share of invocations failed with networking errors and no application log output. The functions were attached to two small subnets shared with other services. Every invocation also opened a fresh database connection at handler scope rather than reusing one, so a burst simultaneously exhausted subnet addresses and the database's connection limit.
VPC-attached AWS Lambda functions reaching private databases and internal services, with sharp intraday traffic bursts. AceMQ works on the customer's function configuration, networking design, and connection handling — the AWS platform itself is Amazon's.
AceMQ correlated failed invocations against subnet address utilization and concurrency to confirm exhaustion as the cause rather than an application fault. We then addressed both sides: enough address space and interface capacity to absorb the burst, and connection reuse so the database is not attacked by the same burst.
The market-open failures stopped, and database connection counts during bursts fell dramatically once connections were reused rather than created per invocation.
Breaking a redrive loop where SQS messages were reprocessed indefinitely because the queue visibility timeout was shorter than the Lambda function timeout.
Designing event-source mapping, batching, ordering, and failure handling for a Lambda estate that had grown without a consistent event architecture.
Whether you need architecture advisory, 24/7 support, or full managed services, AceMQ has the expertise to help.