Engineering Logs for Troubleshooting & Debugging
Problem – Model Weight Synchronization Lag Behind Nginx Load Balancer In a staging environment we run three Docker‑based inference replicas behind an Nginx upstream. Model artifacts are stored on a shared NFS mount and are updated by a CI/CD pipeline that copies a new .pt file into /models. After each deployment the expectation is that … Read more
Problem: “Storage class not found” error during LlamaIndex index initialization in a hybrid Kubernetes deployment LlamaIndex attempts to create a PersistentVolumeClaim (PVC) for the vector‑store backend (e.g., S3, Azure Blob) using the storage_class_name supplied in its configuration. In a mixed on‑prem / cloud environment the pod fails to start and the following error appears in … Read more
Problem Description During a rolling deployment of DeepSeek on a 5‑node GKE cluster, API calls to /v1/collections started failing with a runtime exception. The failure manifested as: java.lang.RuntimeException: Failed to write collection to PostgreSQL at com.deepseek.service.CollectionService.create(CollectionService.java:112) Caused by: org.postgresql.util.PSQLException: Connection is closed at org.postgresql.core.v3.ConnectionFactoryImpl.openConnectionImpl(ConnectionFactoryImpl.java:247) Additional logs showed HikariCP pool timeouts: HikariPool-1 – Connection is not … Read more
Problem Description After a Helm upgrade of the haproxy-ingress chart, the HAProxy pods enter CrashLoopBackOff. The container logs show errors such as: Error opening configuration file /etc/haproxy/haproxy.cfg: No such file or directory MountVolume.SetUp failed for volume “haproxy-config”: configmap “haproxy-config” not found cannot open /etc/haproxy/haproxy.cfg: permission denied failed to reload haproxy: configuration file is not readable … Read more
Problem Description During integration tests in the staging environment, the inference service crashes when loading a Hugging Face dataset with a custom filter. The failure manifests as a datasets.exceptions.FilterParseError raised by the datasets.Dataset.filter utility. Typical log excerpt: Traceback (most recent call last): File “/app/load_data.py”, line 42, in <module> ds = load_dataset(“my_dataset”, split=”train”).filter(filter_expr) File “…/site-packages/datasets/dataset_dict.py”, line 1234, … Read more
Problem Description A blue‑green rollout of a Hugging Face transformers service on Kubernetes fails during container start‑up. The new pods report: MountVolume.SetUp failed for volume “model-pvc”: permission denied, are you root? … OSError: [Errno 13] Permission denied: ‘/model/pytorch_model.bin’ Traceback (most recent call last): File “/app/serve.py”, line 42, in <module> model = AutoModel.from_pretrained(“/model”) File “…/transformers/modeling_utils.py”, line … Read more
Problem Description During a canary rollout of a LangChain RetrievalQA service on a Kubernetes cluster, the API began returning empty strings or irrelevant text despite logs confirming that documents were successfully retrieved from Pinecone. The stable version of the service continues to produce correct, concise answers, while the canary pods intermittently emit responses such as: … Read more
Problem – CRD Validation Rejects AMD GPU Specification in Deployment Manifest When deploying an AI inference service that requires an AMD GPU, the kubectl apply -f deployment.yaml command fails with a validation error from the AMD GPU admission webhook. Typical error output looks like: error: admission webhook “validate.amd.com” denied the request: spec.template.spec.containers[0].resources.limits.amd.com/gpu: Invalid value: “1” … Read more
TGI checkpoint storage class not found after A/B deployment Problem During an A/B testing rollout of Text Generation Inference (TGI) instances, the newly created replica fails to start and logs an error similar to: Failed to load checkpoint: storage class “fast-ssd” not found Other observed symptoms include: Pod tgi-a-12345 stays in Pending state. kubectl describe … Read more
Problem When deploying a Mistral AI inference job through a Knative Eventing pipeline, the custom resource (CR) creation fails with a validation error from the Kubernetes API server: error: admission webhook “mistral-ai-validation.k8s.io” denied the request: spec.modelVersion: Required value: missing required field “spec.modelVersion” spec.resources.limits.cpu: Invalid value: “500m”: must be an integer spec.parameters: Additional property foo is not … Read more