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    onboarding

    • Set Up Local Network Access
    • Open WebUI with Ollama

    data science

    • Single-cell RNA Sequencing
    • Portfolio Optimization
    • CUDA-X Data Science
    • Build Knowledge Graphs with txt2kg
    • Optimized JAX

    tools

    • DGX Dashboard
    • RAG Application in AI Workbench
    • Set up Tailscale on Your Spark
    • VS Code
    • Connect Three DGX Spark in a Ring Topology
    • Connect Multiple DGX Spark through a Switch

    fine tuning

    • FLUX.1 Dreambooth LoRA Fine-tuning
    • LLaMA Factory
    • Fine-tune with NeMo
    • Fine-tune with Pytorch
    • Unsloth on DGX Spark

    use case

    • Run Hermes Agent with a Local LLM
    • cuTile Kernels
    • CLI Coding Agent
    • Run NemoClaw with a Local LLM
    • 🦞 Set Up Example NemoClaw Agents 🦞
    • Live VLM WebUI
    • Install and Use Isaac Sim and Isaac Lab
    • Vibe Coding in VS Code
    • Build and Deploy a Multi-Agent Chatbot
    • Connect Two Sparks
    • NCCL for Multiple Sparks
    • Build a Video Search and Summarization (VSS) Agent
    • Spark & Reachy Photo Booth
    • Secure AI Agents with OpenShell
    • Run OpenClaw with a Local LLM

    inference

    • Generate Images and Videos with ComfyUI
    • Serve LLMs with vLLM
    • Speculative Decoding
    • Run models with llama.cpp on DGX Spark
    • Nemotron Model Family on DGX Spark
    • Serve LLMs with SGLang
    • TRT LLM for Inference
    • Quantize Models to NVFP4 with NVIDIA Model Optimizer
    • Multi-modal Inference
    • NIM on Spark
    • LM Studio on DGX Spark

    NCCL for Multiple Sparks

    30 MIN

    Install and test NCCL on two, three, or four Sparks

    • DGX
    • Spark
    OverviewOverviewRun on two SparksRun on two SparksRun on three SparksRun on three SparksRun on four SparksRun on four SparksTroubleshootingTroubleshooting

    Common issues for running on multiple Sparks

    IssueCauseSolution
    mpirun hangs or times outSSH connectivity issues1. Test basic SSH connectivity: ssh <remote_ip> should work without password prompts
    2. Try a simple mpirun test: mpirun -np 2 -H <IP for Node 1>:1,<IP for Node 2>:1 hostname
    3. Verify SSH keys are setup correctly for all nodes
    Network interface not foundWrong interface name or down statusCheck interface status with ibdev2netdev and verify IP configuration
    NCCL build failsMissing dependencies such as OpenMPI or incorrect CUDA versionVerify CUDA installation and required libraries are present

    Resources

    • NCCL Documentation
    • DGX Spark Documentation
    • DGX Spark Forum
    • DGX Spark User Performance Guide
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