Chapter 4. Configuring persistent storage and inferencing the model

Procedure

1. In the disconnected OpenShift Container Platform cluster, configure persistent storage using Network File System (NFS).

2. Create a Deployment custom resource (CR). For example, the following Deployment CR uses AI Inference Server to serve a Granite model on a CUDA accelerator.

   apiVersion: apps/v1
   kind: Deployment
   metadata:
     name: granite
     namespace: rhaiis-namespace 

   1

   
     labels:
       app: granite
   spec:
     replicas: 0
     selector:
       matchLabels:
         app: granite
     template:
       metadata:
         labels:
           app: granite
       spec:
         containers:
           - name: granite
             image: 'registry.redhat.io/rhaiis/vllm-cuda-rhel9@sha256:137ac606b87679c90658985ef1fc9a26a97bb11f622b988fe5125f33e6f35d78'
             imagePullPolicy: IfNotPresent
             command:
               - python
               - '-m'
               - vllm.entrypoints.openai.api_server
             args:
               - '--port=8000'
               - '--model=/mnt/models'
               - '--served-model-name=granite-3.1-2b-instruct-quantized.w8a8'
               - '--tensor-parallel-size=1'
             resources:
               limits:
                 cpu: '10'
                 nvidia.com/gpu: '1'
               requests:
                 cpu: '2'
                 memory: 6Gi
                 nvidia.com/gpu: '1'
             volumeMounts:
               - name: cache-volume
                 mountPath: /mnt/models
               - name: shm
                 mountPath: /dev/shm 

   2

   
         volumes:
           - name: cache-volume
             persistentVolumeClaim:
               claimName: granite-31-w8a8
           - name: shm
             emptyDir:
               medium: Memory
               sizeLimit: 2Gi
         restartPolicy: Always

   1

   The metadata.namespace value must match the namespace where you configure the Hugging Face Secret CR.

   2

   The /dev/shm volume mount is required by the NVIDIA Collective Communications Library (NCCL). Tensor parallel vLLM deployments fail when the /dev/shm volume mount is not set.

3. Create a Service CR for the model inference. For example:

   apiVersion: v1
   kind: Service
   metadata:
     name: granite
     namespace: rhaiis-namespace
   spec:
     selector:
       app: granite
     ports:
       - protocol: TCP
         port: 80
         targetPort: 8000

4. Optional. Create a Route CR to enable public access to the model. For example:

   apiVersion: route.openshift.io/v1
   kind: Route
   metadata:
     name: granite
     namespace: rhaiis-namespace
   spec:
     to:
       kind: Service
       name: granite
     port:
       targetPort: 80

5. Get the URL for the exposed route:

   $ oc get route granite -n rhaiis-namespace -o jsonpath='{.spec.host}'

   Example output

   granite-rhaiis-namespace.apps.example.com

6. Query the model by running the following command:

   curl -X POST http://granite-rhaiis-namespace.apps.example.com/v1/chat/completions \
     -H "Content-Type: application/json" \
     -d '{
       "model": "granite-3.1-2b-instruct-quantized.w8a8",
       "messages": [{"role": "user", "content": "What is AI?"}],
       "temperature": 0.1
     }'