# Troubleshooting

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# Troubleshooting

| Field | Value |
| --- | --- |
| Distribution | WCT English — OpenC5ISR |
| Product | OpenC5ISR |
| Release | 0.15.1 |
| Deployment | `openc5isr-en.wallacecorptech.com` |
| Source | `/srv/wct/releases/OpenC5ISR-v0.15.0` |
| Evidence | Operational diagnostic standard |
| Source fingerprint | `63d2b1097707e25d666401cdc6362e395968600a40a08690210cd8c0b75fbf50` |
| Status | Generated baseline — human review required |

> **Verification boundary:** This page combines platform design guidance with static evidence from the release. It does not prove that every detected interface is enabled, reachable, secure, or operational in the deployed environment.

## Diagnostic sequence

1. State the exact user-visible symptom, start time, scope and last known good state.
2. Check DNS/routing/time before assuming an application defect.
3. Check process/container state and recent logs.
4. Test the backend locally on its bound address/port.
5. Test proxy/TLS path and WebSocket upgrade separately.
6. Test dependencies: database, OpenBus, OpenKnowledge, OpenFiles and external services.
7. Reproduce one primary workflow with correlation identifiers and capture evidence.
8. Apply the smallest reversible change, then retest all layers.

## Symptom matrix

| Symptom | Likely layer | First checks |
| --- | --- | --- |
| Connection refused | Process/socket | `systemctl status`, `ss -lntup`, local curl |
| Empty response/reset | App/upstream crash or protocol mismatch | Application logs, internal HTTP response, proxy protocol. |
| 502/504 | Reverse proxy/upstream | `nginx -t`, error log, `proxy_pass`, backend latency |
| Page loads but live data fails | WebSocket/CORS/auth | Browser network console, upgrade headers, token/role, route base. |
| Wrong distribution/branding | Nginx/service instance | Hostname routing, service unit, current release symlink, environment. |
| Tracks/tasks/products missing | Dependency/data flow | Producer logs, OpenBus/API, authorization, semantic type, time window. |
| Intermittent correlation error | Time/PNT/data quality | Clock offset, source timestamps, coordinate frame and calibration. |

## Evidence rule

Before changing configuration, preserve the relevant logs, status output, request/response, release version and timestamps. Troubleshooting without evidence tends to become configuration roulette—with worse odds and fewer free drinks.
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## Maintainer Notes

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Add human-reviewed deployment notes, corrections, decisions, screenshots, and links here. Content outside the generated block is preserved on future runs.
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