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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
  • Text to Knowledge Graph
  • Optimized JAX

tools

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

fine tuning

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

use case

  • NemoClaw with Nemotron 3 Super and Telegram on DGX Spark
  • Secure Long Running AI Agents with OpenShell on DGX Spark
  • OpenClaw 🦞
  • 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 Two Sparks
  • Build a Video Search and Summarization (VSS) Agent
  • Spark & Reachy Photo Booth

inference

  • Speculative Decoding
  • Run models with llama.cpp on DGX Spark
  • vLLM for Inference
  • Nemotron-3-Nano with llama.cpp
  • SGLang for Inference
  • TRT LLM for Inference
  • NVFP4 Quantization
  • Multi-modal Inference
  • NIM on Spark
  • LM Studio on DGX Spark

NCCL for Two Sparks

30 MIN

Install and test NCCL on two Sparks

DGXSpark
OverviewOverviewRun on two SparksRun on two SparksTroubleshootingTroubleshooting

Common issues for running on two Spark

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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