Engineering Logs for Troubleshooting & Debugging
Problem During Retrieval‑Augmented Generation (RAG) inference, the Weaviate NearVector similarity query returns an empty result set even though the target documents are present in the vector store. The downstream LLM receives no context, leading to hallucinations or generic answers. Root Cause The empty results stem from one or more of the following intertwined issues: Vector … Read more
Problem – Nightly RAG Ingestion Fails with Weaviate Connection Timeouts The automated Retrieval‑Augmented Generation (RAG) pipeline runs every night to ingest fresh documents, generate embeddings, and store them in a Weaviate vector store. Since the last deployment, the pipeline aborts during the store_vectors step with repeated connection timeout errors and occasional authentication failures. No new … Read more
Problem – Streaming queries never terminate after stop‑sequence trigger fails In a high‑throughput real‑time pipeline that ingests and queries vectors via Weaviate’s gRPC API, clients observed that streaming GraphQL queries kept the connection open indefinitely. The expected stop sequence (e.g., \n\n) never caused the server to close the stream, resulting in: Growing memory usage on … Read more
Problem – Shard Rebalancing Timeout After Autoscaling Nodes In an inference‑serving deployment of Weaviate, automatic scaling of worker nodes frequently triggers a cascade of errors: Search requests return 504 Gateway Timeout or stale vectors. Cluster logs contain repeated messages such as: rebalance_timeout: shard “shard-7” could not be moved within the configured timeout Metrics show CPU … Read more
Problem – RAG Prompt Rendering Failure After Updating Template Placeholders In a staging deployment of Weaviate (Docker Compose, PostgreSQL vector store, generative AI module v1.22), updating the prompt_template.yaml to replace the built‑in {{question}} placeholder with a custom name (e.g., {{user_query}}) caused the generative endpoint to return HTTP 500. The logs contain errors such as: Error rendering … Read more
Problem: Weaviate text generation ignores the configured stop sequence on edge nodes When running the /v1/generate endpoint on resource‑constrained edge devices (e.g., ARM64 Jetson Nano, Raspberry Pi, or IoT gateway VMs), the LLM backend continues producing tokens past the user‑defined stop sequence. The symptom is a runaway response that quickly exhausts memory and CPU, often ending … Read more
Problem In a Google Kubernetes Engine (GKE) cluster running a Weaviate deployment, the weaviate-scheduler pods remain in the Pending state indefinitely. The kubectl describe pod output shows a scheduling failure related to node selector constraints, despite apparent node capacity. Root Cause The Weaviate Helm chart defines a nodeSelector for the scheduler component that targets a … Read more
Problem Description During an A/B test of two client variants that access a Weaviate cluster, token acquisition from the OAuth2 provider becomes flaky. Approximately 10‑20 % of /token requests return HTTP 401 or 500, causing downstream API calls to be denied. The failure is intermittent: the same client ID can succeed in one request and fail in … Read more
Problem Description A production Weaviate cluster exhibited a growing replica synchronization lag after a canary deployment that introduced a new Docker image and an updated vector index schema. The primary node continued to accept writes, but replica nodes reported the following errors in their logs: 2024-07-31T14:22:13Z replica_sync_timeout: replica did not acknowledge write within configured timeout. … Read more
Problem: Weaviate client batch size exceeded during document ingestion During a large‑scale ingestion run on a self‑hosted Weaviate instance (32 GB RAM, Docker Compose), the Python client started failing after a few hundred documents. The failure manifested as HTTP 413 “Payload Too Large” responses and a subsequent cascade of aborted GraphQL mutations, ultimately causing data loss. Typical … Read more