Distributed Systems

RAG prompt template rendering error during performance benchmark on Kubernetes

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Problem The retrieval‑augmented generation (RAG) service deployed on a Kubernetes cluster fails during the performance benchmark phase with a prompt template rendering error. The error appears only under load and aborts the benchmark run, causing the following observable symptoms: Benchmark client receives HTTP 500 responses with body {“error”:”PromptTemplateError: variable ‘context’ is undefined”}. Pod logs contain stack … Read more

Docker batch ingestion timeout intermittent during large file processing

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Problem: Intermittent Docker Batch Ingestion Timeout on Large Files In a production data pipeline, a batch ingestion service runs inside a Docker container. When processing files larger than ~2 GB, the job occasionally aborts with a timeout error and reports partial data load. The failure is non‑deterministic: the same file can succeed on one run and … Read more

401 error from AI inference pod after SAML assertion validation fails

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401 error from AI inference pod after SAML assertion validation fails Problem In a Kubernetes‑hosted microservices platform, the AI inference service (ai‑model‑svc) began returning HTTP 401 responses for internal calls that should be authenticated via SAML‑based SSO. The failure is logged as “SAML assertion invalid” by the authentication middleware, causing downstream clients to see a hard … Read more

nginx fails to start with filter expression parse error after CI templating

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Problem – Nginx Fails to Start with “filter expression parse error” After CI Templating During the CI/CD pipeline the Nginx configuration is generated from a Jinja‑like template that is populated with environment‑specific variables. After the deployment step the nginx service aborts with a filter expression parse error, preventing the web tier from coming online. Typical … Read more

nginx pods PVC pending after multi-region Kubernetes rollout

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Problem During a staged rollout of nginx across three AWS regions (us-east-1, eu-west-1, ap-southeast-2) the newly created pods repeatedly entered the Pending phase because their PersistentVolumeClaims (PVCs) could not be bound. The issue manifested only after the rollout controller applied the StatefulSet manifest that references a StorageClass with volumeBindingMode: WaitForFirstConsumer. Operators observed the following symptoms: … Read more

Kubernetes NetworkPolicy blocking API gateway inbound traffic after policy update

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Problem The API gateway service (gateway-prod) suddenly stopped receiving inbound HTTP requests after a routine NetworkPolicy update. The symptom manifested as 5xx errors from downstream services and connection timeouts observed by clients. Observed logs 2026-10-05T14:32:10.123Z kubelet[1234]: E0905 14:32:10.123456 1234 network_plugin.go:215] Failed to program iptables rules: iptables-restore v1.8.4: line 23: Invalid argument 2026-10-05T14:32:10.124Z kube-proxy[5678]: I0905 14:32:10.124567 … Read more

HPA not scaling HAProxy pods in dev sandbox despite CPU spike

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Problem In a development sandbox (a local kind cluster) the haproxy deployment is configured with a Horizontal Pod Autoscaler (HPA) that should react to both CPU utilization and a custom request‑latency metric. During load testing of an AI model serving pipeline the following symptoms appear: Average request latency climbs from ~30 ms to >500 ms. CPU usage … Read more

Nginx upstream request body empty for LLM after adding context injection

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Nginx upstream request body empty for LLM after adding context injection Problem After deploying a retrieval‑augmented generation (RAG) pipeline, the Nginx reverse proxy stopped sending the retrieved documents (or their metadata) to the LLM backend. The upstream request body received by the LLM is empty, resulting in generic or nonsensical completions. The failure appeared only … Read more

Docker inference worker queue backlog causing latency spikes in streaming

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Problem: Inference Queue Backlog Causing Latency Spikes in Real‑Time Streaming A high‑throughput video streaming service runs a fleet of Docker containers, each hosting an AI inference worker that processes incoming frames. Over the past weeks the pipeline has exhibited intermittent latency spikes and dropped frames. Monitoring shows a growing backlog in the internal inference queue, … Read more

Docker container start failure mounting cloud volume after HTTP 500

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Problem In a production AI inference service, Docker containers repeatedly fail to start with an error similar to: docker: Error response from daemon: mount volume “cloud-volume-01” failed: cloud provider API returned 500 Internal Server Error Typical symptoms observed: Container creation logs end with MountVolume.SetUp failed for volume “cloud-volume-01”. Docker daemon logs contain repeated HTTP 500 … Read more