Engineering Logs for Troubleshooting & Debugging
Jordan Lee 
Problem Description In a hybrid‑cloud deployment of a Retrieval‑Augmented Generation (RAG) pipeline that uses vLLM for inference, the retrieval step consistently returns an empty list or null despite: Valid user queries arriving at the API endpoint. Document embeddings successfully indexed in the vector store (e.g., Milvus or Pinecone). No errors reported by the vLLM server … Read more
Problem Description The data‑pipeline service, defined in a docker‑compose.yml file, attempts to call the API server at http://api:5000/api during ingestion. The call consistently fails with either a timeout or a connection‑refused error, causing the pipeline to abort. Typical log excerpts: pipeline | 2026-06-12T08:14:32Z ERROR: dial tcp 172.18.0.3:5000: connect: connection refused pipeline | 2026-06-12T08:14:32Z ERROR: Get … Read more
Problem – HAProxy traffic imbalance during a blue‑green deployment During a scheduled blue‑green rollout of a new service version, the production HAProxy 2.8 front‑end observed a ~40 % increase in query latency. The spike appeared only after the first batch of green servers was added to the blue_green backend and persisted until the rollout completed. Typical … Read more
Problem – ONNX Runtime Inference Fails After CI/CD Deployment During a routine CI/CD rollout, newly built ONNX model containers are deployed to a Kubernetes cluster. After the deployment completes, API calls that should hit the onnx-runtime service return HTTP 502/504 errors and the ONNX Runtime logs show Failed to load model: file not found. The … Read more
Problem – PostgreSQL HPA Not Scaling Under High CPU Usage The PostgreSQL deployment runs in a Kubernetes cluster that is part of an AI‑driven orchestration platform. During traffic spikes the API gateway generates thousands of concurrent requests per second, causing PostgreSQL CPU utilization to rise sharply. Expected behavior is that the Horizontal Pod Autoscaler (HPA) … Read more
Problem – Gemini Hybrid Search Scoring Inconsistency in an Air‑Gapped Deployment Engineers deploying Google Gemini in a hybrid search configuration (vector + keyword) inside an air‑gapped environment have reported that the relevance scores returned for the same query differ dramatically between the local vector database and the remote knowledge‑base (KB) component. Typical manifestations include: Score … Read more
Problem – CRD validation failure due to tensor dimension mismatch During a multi‑node distributed training run, the pipeline aborts with a validation error similar to: ValueError: Expected tensor of shape (N, C, H, W) but got (N, C, H, W, 1) – CRD validation failed Other observed symptoms include: Inconsistent batch shapes reported by the … Read more
Problem – OAuth2 Token Refresh Fails on Edge Nodes In a remote industrial monitoring deployment an edge‑computing node runs PostgreSQL 15 with OAuth2‑based client authentication. When the network latency to the central authentication service exceeds a few hundred milliseconds, connections are abruptly terminated and the following errors appear in the PostgreSQL log: 2024-05-12 10:23:45.123 UTC … Read more
Problem Description In an air‑gapped Kubernetes cluster the Elasticsearch scheduler pod (managed by the Elastic Cloud on Kubernetes (ECK) operator) remains in Pending with events such as: Events: Type Reason Age From Message —- —— —- —- ——- Warning FailedScheduling 2m default-scheduler 0/5 nodes are available: 5 Insufficient cpu. Warning FailedScheduling 2m default-scheduler 0/5 nodes … Read more
Problem – ConfigMap/Secret Mount Errors in a Multi‑Region Haystack Deployment In a production Haystack deployment spanning multiple AWS regions, pods repeatedly fail during initialization with messages such as: Error: “failed to sync config: open /etc/haystack/config.yaml: no such file or directory” MountVolume.SetUp failed for volume “config” : hostPath type check failed: path /etc/haystack does not exist … Read more