For runpod gpu platform and training engineers

Separate container socket misrouting from a true worker stall on RunPod.

Keep container network interface bindings, Pod or Instant Cluster lifecycle logs, and rank-0 rendezvous traces beside the first ProcessGroupNCCL watchdog exception.

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Free 30-day Team evaluation. No card or automatic subscription. Work email verification required.

Live diagnosis, no signup

Replay a resolved RunPod multi-node training incident

Upload your log file. Review the selected evidence and masking, then run diagnosis. Keep the original log for any follow-up questions.

Before uploading, review cloud data handling and local options.

training_logs.txt

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Upload or drop a plain-text log

Upload your log file. Large files are processed in your browser. Only selected evidence is submitted when you run diagnosis.

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No credit card. No automatic subscription. See whether Denpex helps with an incident you already understand.

Start your free 30-day Team evaluation

Up to 50 diagnoses a day for 30 days. Verify your work email to activate an eligible company evaluation, then replay a resolved incident and compare the evidence and next steps with your team's confirmed cause.

What a useful evaluation should establish

Compare the proposed failure class, quoted evidence, and suggested ownership with your resolved ticket. A useful handoff distinguishes container networking symptoms from true GPU hardware drops.

Use Denpex alongside your existing telemetry tools to investigate submitted incident evidence. With monitoring configured on a supported plan, detected failures can trigger alerts and an automatic diagnosis from the captured evidence.

Inside Denpex

See the evidence, not just the claim

Follow the causal chain, inspect the quoted evidence and prepare the next handoff. These actual product captures use founder-account examples and the VS Code extension, with the source identified under each image. Open a capture to inspect it at full size.

Denpex founder-account example: a causal graph connects an Xid 48 ECC event to a rank exit and downstream collective failures, with quoted evidence for each stage. — Live founder-account capture from the bundled NCCL/ECC example. Follow the hardware event, rank exit and downstream symptoms with a supporting log quote at each stage.Inspect original image

Denpex hardware handoff summary asks the operator to capture diagnostic evidence and verify RMA eligibility with the vendor. — Actual hardware handoff summary from the same founder-account example. Capture diagnostic evidence before an approved reset, then confirm RMA eligibility with the vendor.Inspect original image

Denpex historical example says a collective timeout does not establish the initiating rank, cause or failure domain and requests distinguishing evidence before a remedy. — Founder-account example restored from history. The original timeout remains unattributed, and the UI keeps the missing-evidence assessment visible.Inspect original image

Denpex VS Code extension displaying a bundled OOM-before-NCCL example, matched log evidence, verification guidance and an investigation handoff. — Actual VS Code extension capture of the bundled OOM-before-NCCL example. Review matched log evidence, verification guidance and the investigation handoff without leaving the editor.Inspect original image

Failure Signature Triage

RunPod - Observed Runtime Evidence

Read RunPod documentation

Incident pattern summary

A 2-node PyTorch DDP run on RunPod hits WorkNCCL collective timeout during AllReduce. Preserve NCCL_DEBUG=INFO interface initialization logs to verify whether NCCL attempted to bind docker0 or eth0 before treating the timeout as a hardware fault.

Terminal traceback excerpt (RunPod)

[E ProcessGroupNCCL.cpp:915] [Rank 0] Watchdog caught collective operation timeout: WorkNCCL(SeqNum=4, OpType=ALLREDUCE, NumelIn=67108864, Timeout(ms)=600000) ran for 600082 ms before timing out.
runpod-worker-0:142:189 [0] NCCL INFO Bootstrap : Using eth0:10.244.1.18<0>
runpod-worker-0:142:189 [0] NCCL WARN Connect to 172.17.0.1<49211> failed : Connection timed out

Recommended verification flags

Set these environment flags in your training container or launch script to capture high-resolution collective logs:

NCCL_DEBUG=INFONCCL_SOCKET_IFNAME=eth0TORCH_DISTRIBUTED_DEBUG=DETAILTORCH_NCCL_ASYNC_ERROR_HANDLING=1

Diagnostic Scope Boundary

Denpex cannot inspect private RunPod hypervisor state from a log upload or reconfigure container virtual NICs. The evaluation structures log evidence for your engineering and provider support handoff.