Chapter 3. Serving and inferencing with AI Inference Server
Serve and inference a large language model with Red Hat AI Inference Server.
Prerequisites
- You have installed Podman or Docker
You have access to a Linux server with NVIDIA or AMD GPUs and are logged in as a user with root privileges
For NVIDIA GPUs:
- Install NVIDIA drivers
- Install the NVIDIA Container Toolkit
- If your system has multiple NVIDIA GPUs that use NVswitch, you must have root access to start Fabric Manager
For AMD GPUs:
- Install ROCm software
Verify that you can run ROCm containers
-
You have access to
registry.redhat.ioand have logged in - You have a Hugging Face account and have generated a Hugging Face token
-
You have access to
NoteAMD GPUs support FP8 (W8A8) and GGUF quantization schemes only. For more information, see Supported hardware.
Procedure
Using the table below, identify the correct image for your infrastructure.
Expand GPU AI Inference Server image NVIDIA CUDA (T4, A100, L4, L40, L40S, H100, H200, B200)
registry.redhat.io/rhaiis/vllm-cuda-rhel9:3.1.0AMD ROCm (MI210, MI300X)
registry.redhat.io/rhaiis/vllm-rocm-rhel9:3.1.0Open a terminal on your server host, and log in to
registry.redhat.io:$ podman login registry.redhat.ioPull the relevant image for your GPUs:
$ podman pull registry.redhat.io/rhaiis/vllm-<gpu_type>-rhel9:3.1.0If your system has SELinux enabled, configure SELinux to allow device access:
$ sudo setsebool -P container_use_devices 1Create a volume and mount it into the container. Adjust the container permissions so that the container can use it.
$ mkdir -p rhaiis-cache$ chmod g+rwX rhaiis-cacheCreate or append your
HF_TOKENHugging Face token to theprivate.envfile. Source theprivate.envfile.$ echo "export HF_TOKEN=<your_HF_token>" > private.env$ source private.envStart the AI Inference Server container image.
For NVIDIA CUDA accelerators:
If the host system has multiple GPUs and uses NVSwitch, then start NVIDIA Fabric Manager. To detect if your system is using NVSwitch, first check if files are present in
/proc/driver/nvidia-nvswitch/devices/, and then start NVIDIA Fabric Manager. Starting NVIDIA Fabric Manager requires root privileges.$ ls /proc/driver/nvidia-nvswitch/devices/Example output
0000:0c:09.0 0000:0c:0a.0 0000:0c:0b.0 0000:0c:0c.0 0000:0c:0d.0 0000:0c:0e.0$ systemctl start nvidia-fabricmanagerImportantNVIDIA Fabric Manager is only required on systems with multiple GPUs that use NVswitch. For more information, see NVIDIA Server Architectures.
Check that the Red Hat AI Inference Server container can access NVIDIA GPUs on the host by running the following command:
$ podman run --rm -it \ --security-opt=label=disable \ --device nvidia.com/gpu=all \ nvcr.io/nvidia/cuda:12.4.1-base-ubi9 \ nvidia-smiExample output
+-----------------------------------------------------------------------------------------+ | NVIDIA-SMI 570.124.06 Driver Version: 570.124.06 CUDA Version: 12.8 | |-----------------------------------------+------------------------+----------------------+ | GPU Name Persistence-M | Bus-Id Disp.A | Volatile Uncorr. ECC | | Fan Temp Perf Pwr:Usage/Cap | Memory-Usage | GPU-Util Compute M. | | | | MIG M. | |=========================================+========================+======================| | 0 NVIDIA A100-SXM4-80GB Off | 00000000:08:01.0 Off | 0 | | N/A 32C P0 64W / 400W | 1MiB / 81920MiB | 0% Default | | | | Disabled | +-----------------------------------------+------------------------+----------------------+ | 1 NVIDIA A100-SXM4-80GB Off | 00000000:08:02.0 Off | 0 | | N/A 29C P0 63W / 400W | 1MiB / 81920MiB | 0% Default | | | | Disabled | +-----------------------------------------+------------------------+----------------------+ +-----------------------------------------------------------------------------------------+ | Processes: | | GPU GI CI PID Type Process name GPU Memory | | ID ID Usage | |=========================================================================================| | No running processes found | +-----------------------------------------------------------------------------------------+Start the container.
$ podman run --rm -it \ --device nvidia.com/gpu=all \ --security-opt=label=disable \1 --shm-size=4g -p 8000:8000 \2 --userns=keep-id:uid=1001 \3 --env "HUGGING_FACE_HUB_TOKEN=$HF_TOKEN" \4 --env "HF_HUB_OFFLINE=0" \ --env=VLLM_NO_USAGE_STATS=1 \ -v ./rhaiis-cache:/opt/app-root/src/.cache:Z \5 registry.redhat.io/rhaiis/vllm-cuda-rhel9:3.1.0 \ --model RedHatAI/Llama-3.2-1B-Instruct-FP8 \ --tensor-parallel-size 26 - 1
- Required for systems where SELinux is enabled.
--security-opt=label=disableprevents SELinux from relabeling files in the volume mount. If you choose not to use this argument, your container might not successfully run. - 2
- If you experience an issue with shared memory, increase
--shm-sizeto8GB. - 3
- Maps the host UID to the effective UID of the vLLM process in the container. You can also pass
--user=0, but this less secure than the--usernsoption. Setting--user=0runs vLLM as root inside the container. - 4
- Set and export
HF_TOKENwith your Hugging Face API access token - 5
- Required for systems where SELinux is enabled. On Debian or Ubuntu operating systems, or when using Docker without SELinux, the
:Zsuffix is not available. - 6
- Set
--tensor-parallel-sizeto match the number of GPUs when running the AI Inference Server container on multiple GPUs.
For AMD ROCm accelerators:
Use
amd-smi static -ato verify that the container can access the host system GPUs:$ podman run -ti --rm --pull=newer \ --security-opt=label=disable \ --device=/dev/kfd --device=/dev/dri \ --group-add keep-groups \1 --entrypoint="" \ registry.redhat.io/rhaiis/vllm-rocm-rhel9:3.1.0 \ amd-smi static -a- 1
- You must belong to both the video and render groups on AMD systems to use the GPUs. To access GPUs, you must pass the
--group-add=keep-groupssupplementary groups option into the container.
Start the container:
podman run --rm -it \ --device /dev/kfd --device /dev/dri \ --security-opt=label=disable \1 --group-add keep-groups \ --shm-size=4GB -p 8000:8000 \2 --env "HUGGING_FACE_HUB_TOKEN=$HF_TOKEN" \ --env "HF_HUB_OFFLINE=0" \ --env=VLLM_NO_USAGE_STATS=1 \ -v ./rhaiis-cache:/opt/app-root/src/.cache \ registry.redhat.io/rhaiis/vllm-rocm-rhel9:3.1.0 \ --model RedHatAI/Llama-3.2-1B-Instruct-FP8 \ --tensor-parallel-size 23 - 1
--security-opt=label=disableprevents SELinux from relabeling files in the volume mount. If you choose not to use this argument, your container might not successfully run.- 2
- If you experience an issue with shared memory, increase
--shm-sizeto8GB. - 3
- Set
--tensor-parallel-sizeto match the number of GPUs when running the AI Inference Server container on multiple GPUs.
In a separate tab in your terminal, make a request to your model with the API.
curl -X POST -H "Content-Type: application/json" -d '{ "prompt": "What is the capital of France?", "max_tokens": 50 }' http://<your_server_ip>:8000/v1/completions | jqExample output
{ "id": "cmpl-b84aeda1d5a4485c9cb9ed4a13072fca", "object": "text_completion", "created": 1746555421, "model": "RedHatAI/Llama-3.2-1B-Instruct-FP8", "choices": [ { "index": 0, "text": " Paris.\nThe capital of France is Paris.", "logprobs": null, "finish_reason": "stop", "stop_reason": null, "prompt_logprobs": null } ], "usage": { "prompt_tokens": 8, "total_tokens": 18, "completion_tokens": 10, "prompt_tokens_details": null } }