xc-llm-ascend/docs/source/installation.md

Installation

This document describes how to install vllm-ascend manually.

Requirements

• OS: Linux
• Python: >= 3.10, < 3.12
• Hardware with Ascend NPUs. It's usually the Atlas 800 A2 series.
• Software:

  Software	Supported version	Note
  Ascend HDK	Refer to the documentation here	Required for CANN
  CANN	== 8.5.1	Required for vllm-ascend and torch-npu
  torch-npu	== 2.9.0	Required for vllm-ascend, No need to install manually, it will be auto installed in below steps
  torch	== 2.9.0	Required for torch-npu and vllm
  NNAL	== 8.5.1	Required for libatb.so, enables advanced tensor operations

There are two installation methods:

• Using pip: first prepare the environment manually or via a CANN image, then install vllm-ascend using pip.
• Using docker: use the vllm-ascend pre-built docker image directly.

Configure Ascend CANN environment

Before installation, you need to make sure firmware/driver, and CANN are installed correctly, refer to Ascend Environment Setup Guide for more details.

Configure hardware environment

To verify that the Ascend NPU firmware and driver were correctly installed, run:

npu-smi info

Refer to Ascend Environment Setup Guide for more details.

Configure software environment

:::::{tab-set} :sync-group: install

::::{tab-item} Before using pip :selected: :sync: pip

The easiest way to prepare your software environment is using CANN image directly:

The CANN prebuilt image includes NNAL (Ascend Neural Network Acceleration Library), which provides libatb.so for advanced tensor operations. No additional installation is required when using the prebuilt image.

   :substitutions:
# Update DEVICE according to your device (/dev/davinci[0-7])
export DEVICE=/dev/davinci7
# Update the vllm-ascend image
export IMAGE=quay.io/ascend/cann:|cann_image_tag|
docker run --rm \
    --name vllm-ascend-env \
    --shm-size=1g \
    --device $DEVICE \
    --device /dev/davinci_manager \
    --device /dev/devmm_svm \
    --device /dev/hisi_hdc \
    -v /usr/local/dcmi:/usr/local/dcmi \
    -v /usr/local/bin/npu-smi:/usr/local/bin/npu-smi \
    -v /usr/local/Ascend/driver/lib64/:/usr/local/Ascend/driver/lib64/ \
    -v /usr/local/Ascend/driver/version.info:/usr/local/Ascend/driver/version.info \
    -v /etc/ascend_install.info:/etc/ascend_install.info \
    -v /root/.cache:/root/.cache \
    -it $IMAGE bash

:::{dropdown} Click here to see "Install CANN manually" :animate: fade-in-slide-down You can also install CANN manually:

If you encounter "libatb.so not found" errors during runtime, please ensure NNAL is properly installed as shown in the manual installation steps below.

# Create a virtual environment.
python -m venv vllm-ascend-env
source vllm-ascend-env/bin/activate

# Install required Python packages.
pip3 install -i https://pypi.tuna.tsinghua.edu.cn/simple attrs 'numpy<2.0.0' decorator sympy cffi pyyaml pathlib2 psutil protobuf scipy requests absl-py wheel typing_extensions

# Download and install the CANN package.
wget --header="Referer: https://www.hiascend.com/" https://ascend-repo.obs.cn-east-2.myhuaweicloud.com/CANN/CANN%208.5.1/Ascend-cann-toolkit_8.5.1_linux-"$(uname -i)".run
chmod +x ./Ascend-cann-toolkit_8.5.1_linux-"$(uname -i)".run
./Ascend-cann-toolkit_8.5.1_linux-"$(uname -i)".run --full
source /usr/local/Ascend/ascend-toolkit/set_env.sh

wget --header="Referer: https://www.hiascend.com/" https://ascend-repo.obs.cn-east-2.myhuaweicloud.com/CANN/CANN%208.5.1/Ascend-cann-910b-ops_8.5.1_linux-"$(uname -i)".run
chmod +x ./Ascend-cann-910b-ops_8.5.1_linux-"$(uname -i)".run
./Ascend-cann-910b-ops_8.5.1_linux-"$(uname -i)".run --install

wget --header="Referer: https://www.hiascend.com/" https://ascend-repo.obs.cn-east-2.myhuaweicloud.com/CANN/CANN%208.5.1/Ascend-cann-nnal_8.5.1_linux-"$(uname -i)".run
chmod +x ./Ascend-cann-nnal_8.5.1_linux-"$(uname -i)".run
./Ascend-cann-nnal_8.5.1_linux-"$(uname -i)".run --install

source /usr/local/Ascend/nnal/atb/set_env.sh

:::

::::

::::{tab-item} Before using docker :sync: docker No extra steps are needed if you are using the vllm-ascend prebuilt Docker image. :::: :::::

Once this is done, you can start to set up vllm and vllm-ascend.

Set up using Python

First, install system dependencies and configure the pip mirror:

# Using apt-get with mirror
sed -i 's|ports.ubuntu.com|mirrors.tuna.tsinghua.edu.cn|g' /etc/apt/sources.list
apt-get update -y && apt-get install -y gcc g++ cmake libnuma-dev wget git curl jq
# Or using yum
# yum update -y && yum install -y gcc g++ cmake numactl-devel wget git curl jq
# Config pip mirror
pip config set global.index-url https://mirrors.tuna.tsinghua.edu.cn/pypi/web/simple

[Optional] Then configure the extra-index of pip if you are working on an x86 machine or using torch-npu dev version:

# For torch-npu dev version or x86 machine
pip config set global.extra-index-url "https://download.pytorch.org/whl/cpu/"

Then you can install vllm and vllm-ascend from a pre-built wheel:

   :substitutions:

# Install vllm-project/vllm. The newest supported version is |vllm_version|.
pip install vllm==|pip_vllm_version|

# Install vllm-project/vllm-ascend from pypi.
pip install vllm-ascend==|pip_vllm_ascend_version|

:::{dropdown} Click here to see "Build from source code" or build from source code:

   :substitutions:

# Install vLLM.
git clone --depth 1 --branch |vllm_version| https://github.com/vllm-project/vllm
cd vllm
VLLM_TARGET_DEVICE=empty pip install -v -e .
cd ..

# Install vLLM Ascend.
git clone --depth 1 --branch |vllm_ascend_version| https://github.com/vllm-project/vllm-ascend.git
cd vllm-ascend
git submodule update --init --recursive
pip install -v -e .
cd ..

If you are building custom operators for Atlas A3, you should run git submodule update --init --recursive manually, or ensure your environment has internet access. :::

To build custom operators, gcc/g++ higher than 8 and C++17 or higher are required. If you are using `pip install -e .` and encounter a torch-npu version conflict, please install with `pip install --no-build-isolation -e .` to build on system env.
If you encounter other problems during compiling, it is probably because an unexpected compiler is being used, you may export `CXX_COMPILER` and `C_COMPILER` in the environment to specify your g++ and gcc locations before compiling.

Set up using Docker

vllm-ascend offers Docker images for deployment. You can just pull the prebuilt image from the image repository ascend/vllm-ascend and run it with bash.

Supported images as following.

image name	Hardware	OS
vllm-ascend:	Atlas A2	Ubuntu
vllm-ascend:-openeuler	Atlas A2	openEuler
vllm-ascend:-a3	Atlas A3	Ubuntu
vllm-ascend:-a3-openeuler	Atlas A3	openEuler
vllm-ascend:-310p	Atlas 300I	Ubuntu
vllm-ascend:-310p-openeuler	Atlas 300I	openEuler

:::{dropdown} Click here to see "Build from Dockerfile" or build IMAGE from source code:

git clone https://github.com/vllm-project/vllm-ascend.git
cd vllm-ascend
docker build -t vllm-ascend-dev-image:latest -f ./Dockerfile .

:::

   :substitutions:

# Update --device according to your device (Atlas A2: /dev/davinci[0-7] Atlas A3:/dev/davinci[0-15]).
# Update the vllm-ascend image according to your environment.
# Note you should download the weight to /root/.cache in advance.
export IMAGE=quay.io/ascend/vllm-ascend:|vllm_ascend_version|
docker run --rm \
    --name vllm-ascend-env \
    --shm-size=1g \
    --net=host \
    --device /dev/davinci0 \
    --device /dev/davinci1 \
    --device /dev/davinci2 \
    --device /dev/davinci3 \
    --device /dev/davinci4 \
    --device /dev/davinci5 \
    --device /dev/davinci6 \
    --device /dev/davinci7 \
    --device /dev/davinci_manager \
    --device /dev/devmm_svm \
    --device /dev/hisi_hdc \
    -v /usr/local/dcmi:/usr/local/dcmi \
    -v /usr/local/Ascend/driver/tools/hccn_tool:/usr/local/Ascend/driver/tools/hccn_tool \
    -v /usr/local/bin/npu-smi:/usr/local/bin/npu-smi \
    -v /usr/local/Ascend/driver/lib64/:/usr/local/Ascend/driver/lib64/ \
    -v /usr/local/Ascend/driver/version.info:/usr/local/Ascend/driver/version.info \
    -v /etc/ascend_install.info:/etc/ascend_install.info \
    -v /root/.cache:/root/.cache \
    -it $IMAGE bash

The default workdir is /workspace, vLLM and vLLM Ascend code are placed in /vllm-workspace and installed in development mode (pip install -e) to help developer immediately take place changes without requiring a new installation.

Extra information

Verify installation

Create and run a simple inference test. The example.py can be like:

from vllm import LLM, SamplingParams

prompts = [
    "Hello, my name is",
    "The president of the United States is",
    "The capital of France is",
    "The future of AI is",
]

# Create a sampling params object.
sampling_params = SamplingParams(temperature=0.8, top_p=0.95)
# Create an LLM.
llm = LLM(model="Qwen/Qwen3-0.6B")

# Generate texts from the prompts.
outputs = llm.generate(prompts, sampling_params)
for output in outputs:
    prompt = output.prompt
    generated_text = output.outputs[0].text
    print(f"Prompt: {prompt!r}, Generated text: {generated_text!r}")

Then run:

python example.py

If you encounter a connection error with Hugging Face (e.g., We couldn't connect to 'https://huggingface.co' to load the files, and couldn't find them in the cached files.), run the following commands to use ModelScope as an alternative:

export VLLM_USE_MODELSCOPE=true
pip install modelscope
python example.py

The output will be like:

INFO 02-18 08:49:58 __init__.py:28] Available plugins for group vllm.platform_plugins:
INFO 02-18 08:49:58 __init__.py:30] name=ascend, value=vllm_ascend:register
INFO 02-18 08:49:58 __init__.py:32] all available plugins for group vllm.platform_plugins will be loaded.
INFO 02-18 08:49:58 __init__.py:34] set environment variable VLLM_PLUGINS to control which plugins to load.
INFO 02-18 08:49:58 __init__.py:42] plugin ascend loaded.
INFO 02-18 08:49:58 __init__.py:174] Platform plugin ascend is activated
INFO 02-18 08:50:12 config.py:526] This model supports multiple tasks: {'embed', 'classify', 'generate', 'score', 'reward'}. Defaulting to 'generate'.
INFO 02-18 08:50:12 llm_engine.py:232] Initializing a V0 LLM engine (v0.7.1) with config: model='./Qwen3-0.6B', speculative_config=None, tokenizer='./Qwen3-0.6B', skip_tokenizer_init=False, tokenizer_mode=auto, revision=None, override_neuron_config=None, tokenizer_revision=None, trust_remote_code=False, dtype=torch.bfloat16, max_seq_len=32768, download_dir=None, load_format=auto, tensor_parallel_size=1, pipeline_parallel_size=1, disable_custom_all_reduce=False, quantization=None, enforce_eager=False, kv_cache_dtype=auto,  device_config=npu, decoding_config=DecodingConfig(guided_decoding_backend='xgrammar'), observability_config=ObservabilityConfig(otlp_traces_endpoint=None, collect_model_forward_time=False, collect_model_execute_time=False), seed=0, served_model_name=./Qwen3-0.6B, num_scheduler_steps=1, multi_step_stream_outputs=True, enable_prefix_caching=False, chunked_prefill_enabled=False, use_async_output_proc=True, disable_mm_preprocessor_cache=False, mm_processor_kwargs=None, pooler_config=None, compilation_config={"splitting_ops":[],"compile_sizes":[],"cudagraph_capture_sizes":[256,248,240,232,224,216,208,200,192,184,176,168,160,152,144,136,128,120,112,104,96,88,80,72,64,56,48,40,32,24,16,8,4,2,1],"max_capture_size":256}, use_cached_outputs=False,
Loading safetensors checkpoint shards:   0% Completed | 0/1 [00:00<?, ?it/s]
Loading safetensors checkpoint shards: 100% Completed | 1/1 [00:00<00:00,  5.86it/s]
Loading safetensors checkpoint shards: 100% Completed | 1/1 [00:00<00:00,  5.85it/s]
INFO 02-18 08:50:24 executor_base.py:108] # CPU blocks: 35064, # CPU blocks: 2730
INFO 02-18 08:50:24 executor_base.py:113] Maximum concurrency for 32768 tokens per request: 136.97x
INFO 02-18 08:50:25 llm_engine.py:429] init engine (profile, create kv cache, warmup model) took 3.87 seconds
Processed prompts: 100%|█████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████| 4/4 [00:00<00:00,  8.46it/s, est. speed input: 46.55 toks/s, output: 135.41 toks/s]
Prompt: 'Hello, my name is', Generated text: " Shinji, a teenage boy from New York City. I'm a computer science"
Prompt: 'The president of the United States is', Generated text: ' a very important person. When he or she is elected, many people think that'
Prompt: 'The capital of France is', Generated text: ' Paris. The oldest part of the city is Saint-Germain-des-Pr'
Prompt: 'The future of AI is', Generated text: ' not bright\n\nThere is no doubt that the evolution of AI will have a huge'

Multi-node Deployment

Verify Multi-Node Communication

First, check physical layer connectivity, then verify each node, and finally verify the inter-node connectivity.

Physical Layer Requirements

• The physical machines must be located on the same WLAN, with network connectivity.
• All NPUs are connected with optical modules, and the connection status must be normal.

Each Node Verification

Execute the following commands on each node in sequence. The results must all be success and the status must be UP:

:::::{tab-set} :sync-group: multi-node

::::{tab-item} A2 series :sync: A2

 # Check the remote switch ports
 for i in {0..7}; do hccn_tool -i $i -lldp -g | grep Ifname; done 
 # Get the link status of the Ethernet ports (UP or DOWN)
 for i in {0..7}; do hccn_tool -i $i -link -g ; done
 # Check the network health status
 for i in {0..7}; do hccn_tool -i $i -net_health -g ; done
 # View the network detected IP configuration
 for i in {0..7}; do hccn_tool -i $i -netdetect -g ; done
 # View gateway configuration
 for i in {0..7}; do hccn_tool -i $i -gateway -g ; done
 # View NPU network configuration
 cat /etc/hccn.conf

:::: ::::{tab-item} A3 series :sync: A3

 # Check the remote switch ports
 for i in {0..15}; do hccn_tool -i $i -lldp -g | grep Ifname; done 
 # Get the link status of the Ethernet ports (UP or DOWN)
 for i in {0..15}; do hccn_tool -i $i -link -g ; done
 # Check the network health status
 for i in {0..15}; do hccn_tool -i $i -net_health -g ; done
 # View the network detected IP configuration
 for i in {0..15}; do hccn_tool -i $i -netdetect -g ; done
 # View gateway configuration
 for i in {0..15}; do hccn_tool -i $i -gateway -g ; done
 # View NPU network configuration
 cat /etc/hccn.conf

:::: :::::

Interconnect Verification

1. Get NPU IP Addresses

:::::{tab-set} :sync-group: multi-node

::::{tab-item} A2 series :sync: A2

for i in {0..7}; do hccn_tool -i $i -ip -g | grep ipaddr; done

:::: ::::{tab-item} A3 series :sync: A3

for i in {0..15}; do hccn_tool -i $i -ip -g | grep ipaddr; done

:::: :::::

2. Cross-Node PING Test

# Execute on the target node (replace with actual IP)
hccn_tool -i 0 -ping -g address x.x.x.x

Run Container In Each Node

Using vLLM-ascend official container is more efficient to run multi-node environment.

Run the following command to start the container in each node (You should download the weight to /root/.cache in advance):

:::::{tab-set} :sync-group: multi-node

::::{tab-item} A2 series :sync: A2

   :substitutions:
# Update the vllm-ascend image
# openEuler:
# export IMAGE=quay.io/ascend/vllm-ascend:|vllm_ascend_version|-openeuler
# Ubuntu:
# export IMAGE=quay.io/ascend/vllm-ascend:|vllm_ascend_version|
export IMAGE=quay.io/ascend/vllm-ascend:|vllm_ascend_version|

# Run the container using the defined variables
# Note if you are running bridge network with docker, Please expose available ports
# for multiple nodes communication in advance
docker run --rm \
--name vllm-ascend \
--net=host \
--shm-size=1g \
--device /dev/davinci0 \
--device /dev/davinci1 \
--device /dev/davinci2 \
--device /dev/davinci3 \
--device /dev/davinci4 \
--device /dev/davinci5 \
--device /dev/davinci6 \
--device /dev/davinci7 \
--device /dev/davinci_manager \
--device /dev/devmm_svm \
--device /dev/hisi_hdc \
-v /usr/local/dcmi:/usr/local/dcmi \
-v /usr/local/Ascend/driver/tools/hccn_tool:/usr/local/Ascend/driver/tools/hccn_tool \
-v /usr/local/bin/npu-smi:/usr/local/bin/npu-smi \
-v /usr/local/Ascend/driver/lib64/:/usr/local/Ascend/driver/lib64/ \
-v /usr/local/Ascend/driver/version.info:/usr/local/Ascend/driver/version.info \
-v /etc/ascend_install.info:/etc/ascend_install.info \
-v /root/.cache:/root/.cache \
-it $IMAGE bash

:::: ::::{tab-item} A3 series :sync: A3

   :substitutions:
# Update the vllm-ascend image
# openEuler:
# export IMAGE=quay.io/ascend/vllm-ascend:|vllm_ascend_version|-a3-openeuler
# Ubuntu:
# export IMAGE=quay.io/ascend/vllm-ascend:|vllm_ascend_version|-a3
export IMAGE=quay.io/ascend/vllm-ascend:|vllm_ascend_version|-a3

# Run the container using the defined variables
# Note if you are running bridge network with docker, Please expose available ports
# for multiple nodes communication in advance
docker run --rm \
--name vllm-ascend \
--net=host \
--shm-size=1g \
--device /dev/davinci0 \
--device /dev/davinci1 \
--device /dev/davinci2 \
--device /dev/davinci3 \
--device /dev/davinci4 \
--device /dev/davinci5 \
--device /dev/davinci6 \
--device /dev/davinci7 \
--device /dev/davinci8 \
--device /dev/davinci9 \
--device /dev/davinci10 \
--device /dev/davinci11 \
--device /dev/davinci12 \
--device /dev/davinci13 \
--device /dev/davinci14 \
--device /dev/davinci15 \
--device /dev/davinci_manager \
--device /dev/devmm_svm \
--device /dev/hisi_hdc \
-v /usr/local/dcmi:/usr/local/dcmi \
-v /usr/local/Ascend/driver/tools/hccn_tool:/usr/local/Ascend/driver/tools/hccn_tool \
-v /usr/local/bin/npu-smi:/usr/local/bin/npu-smi \
-v /usr/local/Ascend/driver/lib64/:/usr/local/Ascend/driver/lib64/ \
-v /usr/local/Ascend/driver/version.info:/usr/local/Ascend/driver/version.info \
-v /etc/ascend_install.info:/etc/ascend_install.info \
-v /root/.cache:/root/.cache \
-it $IMAGE bash

:::: :::::