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Sumit Dhaka
Sumit Dhaka

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I Got Tired of SNMP Dev Hell, So I Built Trishul SNMP Suite

#snmp #python #fastapi #opensource

If you've done serious SNMP work, you know the tax. Terminals full of snmpwalk flags you've looked up three times before. A MIB browser you either paid $500 for or pirated. A trap receiver that only works if three other processes are already running. I built Trishul SNMP Suite to kill that loop — one container, browser UI, free and open source.

The Real Problem: Five Disconnected Tools

SNMP dev work has always forced you to juggle tools that were never designed to work together:

What you need What you're stuck with
Simulate an SNMP agent snmpsim + manual CLI config
Walk a device & read results snmpwalk + manual OID lookup
Send & receive test traps snmptrap + snmptrapd config hell
Browse MIB structures iReasoning ($500+) or a 2003-era Java app
Upload & validate MIBs Text editor + dependency resolution by hand

Every context switch between these tools is friction that slows down development. When something breaks in your NMS integration, you're not sure which layer is wrong. Trishul SNMP Suite collapses all of this into one place.

What Trishul SNMP Suite Actually Is

A self-hosted, browser-based SNMP dev toolkit running in a single Docker container. The backend is FastAPI with SQLite for durable state, powered by two purpose-built Python libraries:

  • trishul-snmp — the in-process async SNMP runtime (responder, manager, trap listener, trap send)
  • trishul-smi — the MIB compiler and bundle pipeline

The frontend is a clean Bootstrap 5 operator shell served directly by FastAPI. No Nginx. No split runtime. No subprocess workers. Just:

curl -LfsS -o install-trishul-snmp-suite.sh \
  https://raw.githubusercontent.com/tosumitdhaka/trishul-snmp-suite/main/install-trishul-snmp-suite.sh \
  && bash install-trishul-snmp-suite.sh up
Enter fullscreen mode Exit fullscreen mode

Open http://localhost:8980. That's your entire SNMP lab, running.

Seven Tools, Zero Context Switching

📊 Dashboard

Live runtime status with an 8-counter activity row — SNMP requests served, OIDs loaded, traps received/sent, walks executed, and more — all driven by WebSocket push. No polling. Counters update the instant something happens and survive container restarts via SQLite-persisted stats.

🖥️ Simulator

Spin up a UDP SNMP responder with custom OIDs and simulation rules: counter, random, timestamp, uptime. Comes with a searchable activity log. Test your NMS integration code against a real SNMP agent without touching any physical hardware.

🚶 Walk & Parse

Run SNMP GET, GETNEXT, GETBULK, and full walks with automatic OID-to-name resolution. Filter, search, and export results to JSON or CSV. Walk history is preserved across sessions.

📡 Traps

Both directions. Send test traps with a full varbind editor to validate your NMS handler formats. Receive live traps with real-time WebSocket display and durable event history — event-time OID resolution included. Ships with a library of 24+ pre-built trap types covering standard and vendor MIBs.

📚 MIB Manager

Drag-and-drop MIB upload with auto-validation on file pick, automatic dependency resolution and fetch, and source-group-aware status tracking. Duplicate shadowing detection means loading overlapping MIBs from different vendors no longer breaks your entire bundle.

🌳 MIB Browser

The iReasoning replacement that lives in your browser. Interactive OID tree with dual views (by module or OID hierarchy), real-time search by name/OID/description, smart type filtering, and lazy child loading so MIBs with 5000+ objects stay snappy.

The killer feature: click any OID or trap you find and jump directly to Walker or Trap Sender with it pre-filled. Your MIB exploration is your test setup — no copy-pasting OID strings, no tab switching.

⚙️ Settings

Auth rotation, auto-start controls for Simulator and Trap Receiver, session timeout, stats export/reset, and product metadata — all in one place.

Why the Architecture Matters

The v2.0 rewrite wasn't cosmetic. The old v1.x model ran the SNMP simulator and trap receiver as separate subprocess workers that communicated with the main FastAPI process via UDP loopback IPC and file-based stats with cross-process locking. It worked, but it was fragile:

  • Startup race conditions in Docker
  • Healthcheck failures blocking container readiness
  • Lost stat updates between competing file writers
  • A broker/adapter layer between API routes and services

trishul-snmp eliminated all of that. The responder, manager (GET/GETNEXT/GETBULK/walk/bulkwalk), notification listener, and trap send all run in-process and async inside the single FastAPI application. No subprocesses. No UDP IPC. No shell-outs. Stats live in SQLite, not files with cross-process locks.

The result: the container starts cleanly, the API surface is flat and predictable (/api/... only), and the WebSocket connection goes directly to FastAPI — no proxy bridging required.

How It Compares to Existing Tools

Tool Cost Self-Hosted SNMP Simulate MIB Browser Trap Send+Receive REST API
iReasoning MIB Browser $500+ ✅ ❌ ✅ ✅ ❌
ManageEngine MIB Browser Freemium ✅ ❌ ✅ Limited ❌
Net-SNMP CLI tools Free ✅ Limited ❌ ✅ ❌
snmpsim Free ✅ ✅ ❌ ❌ ❌
Trishul SNMP Suite Free / OSS ✅ ✅ ✅ ✅ ✅

The Journey: From v1.0 to v2.0.1

The project has shipped continuously since June 2025:

  • v1.0 — Initial release: Simulator, Walker, Traps, MIB Manager, Docker deploy, session auth
  • v1.1.x — Trap enhancements, early MIB Browser, JSON/CSV export, Docker volume persistence, one-command installer
  • v1.2.0 — Full MIB Browser: lazy OID tree, dual views, smart filtering, state persistence, seamless Walker/Trap integration, 24+ trap library
  • v1.2.3–1.2.4 — Complete WebSocket push architecture: live dashboard counters, auto-reconnect client, navbar connection indicator, Settings management with auto-start and session timeout controls
  • v1.2.5 — Drag-and-drop MIB upload, auto-validation on file pick, dark mode
  • v1.3.0 — Security hardening: XSS paths eliminated, WebSocket auth enforced on logout/timeout, MIB upload path traversal fix, remote dependency fetch, MIB Browser view export, test coverage gate
  • v1.4.0 — Single Docker image and canonical installer (trishul-snmp-suite), automatic data migration from the legacy split runtime, Nginx layer removed
  • v2.0.0 — Full backend rewrite: trishul-snmp in-process runtime replaces subprocess workers, trishul-smi bundle pipeline, SQLite state for sessions/notifications/settings, flat /api/... surface
  • v2.0.1 (current) — Port model cleanup (APP_PORT=8980 canonical), structured container logging to stdout/stderr, MIB status model separating active_modules from source_inventory, trap history fix with event-time OID resolution, MIB Browser search preserves active type filter

Who Should Try This

  • NMS and integration developers who need a controllable SNMP agent and trap receiver without real hardware — runs perfectly in CI or staging with docker compose up
  • Network automation engineers adding SNMP to Python/Ansible/NAPALM workflows who want a visual companion to explore and validate OIDs before writing code
  • DevOps and SRE teams building custom Prometheus exporters for legacy SNMP-only hardware (switches, UPS units, routers)
  • Network engineers who explore MIBs daily and are tired of paying for or pirating MIB browser licenses
  • Students and learners — Trishul's UI makes SNMP approachable in a way that the Net-SNMP CLI never was

What it's not: a production 24/7 monitoring system. Use Zabbix, LibreNMS, or PRTG for that. Trishul SNMP Suite is your SNMP workbench — fast to spin up, easy to throw away, and always ready when you need it.

Try It Now 

curl -LfsS -o install-trishul-snmp-suite.sh \
  https://raw.githubusercontent.com/tosumitdhaka/trishul-snmp-suite/main/install-trishul-snmp-suite.sh \
  && bash install-trishul-snmp-suite.sh up
Enter fullscreen mode Exit fullscreen mode

Open http://localhost:8980 — default login admin / admin123. Change it immediately in Settings.

  1. Upload a MIB (start with IF-MIB — dependencies auto-fetch)
  2. Browse the OID tree in the MIB Browser
  3. Start the Simulator with a couple of custom OIDs
  4. Walk it from the Walk & Parse tab
  5. Fire a test trap and watch the Dashboard counter move in real time

GitHub → github.com/tosumitdhaka/trishul-snmp-suite

A ⭐ helps other engineers find it when they're searching for exactly this.

Built with FastAPI · trishul-snmp · trishul-smi · SQLite · Bootstrap 5 · MIT License

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