Vigilmon vs Airbrake: Uptime Monitoring vs Exception Tracking

Airbrake and Vigilmon both show up in conversations about "monitoring." But they are solving fundamentally different problems — and understanding the difference will save your team from the most common monitoring blind spot: assuming that catching exceptions means you'll know when your site goes down.

This article explains what each tool does, where each one fails without the other, and how to run them together for coverage that catches failures at every layer.

What Is Airbrake?

Airbrake is an application error and performance monitoring platform. It integrates with your application via an SDK and captures exceptions, crashes, and performance data from inside your running code.

Airbrake's core capabilities include:

Error tracking: Capture unhandled exceptions with full stack traces, request parameters, user context, and environment metadata
Error grouping and deduplication: Cluster similar exceptions into issues and track frequency, first/last occurrence, and trends over time
Performance monitoring: Identify slow routes, database queries, and external API calls that degrade response times
Deploy tracking: Associate errors with specific code deployments to identify when a regression was introduced
Issue integrations: Connect to GitHub, Jira, Slack, and other tools so errors flow into your existing workflow
Alerting: Threshold and spike-based alerts on error rate or occurrence count

Airbrake is fundamentally a code debugger at runtime. When your application throws an exception, Airbrake is the tool that tells you exactly where it happened, who experienced it, and what sequence of events led there.

What Is Vigilmon?

Vigilmon is a purpose-built external uptime monitoring service. It does not integrate with your application code. It does not receive exception events from an SDK. It sends HTTP requests to your endpoints from multiple geographic locations and alerts you the moment those requests fail or time out.

Vigilmon's core capabilities include:

HTTP/HTTPS endpoint monitoring with status code and response validation
TCP port monitoring for non-HTTP services
Cron job heartbeat monitoring (dead man's switch pattern)
Multi-region consensus alerting — fires only when multiple independent probes agree the target is down
Response time history with configurable period selectors
Webhook, email, and Slack alert channels
Customer-facing status page included with every account
REST API for programmatic monitor management

There is no SDK, no code changes, and no exception grouping. Vigilmon answers a single question: is your service reachable from the outside world right now?

The Core Difference: Inside vs Outside

The most important thing to understand about Airbrake and Vigilmon is where they observe your system from:

Airbrake looks from inside your application. It requires your code to run to produce data. Every insight Airbrake gives you — stack traces, user context, deploy associations — comes from events your application generates.

Vigilmon looks from outside your application. It requires no code to run. It sends HTTP probes from external vantage points and measures what a user would experience: did the server respond, how fast, and with what status code?

This distinction has a concrete consequence:

When your application is completely unreachable — server down, DNS failed, load balancer misconfigured, TLS expired — Airbrake receives nothing. No exceptions are generated. No alerts fire. From Airbrake's perspective, total silence looks identical to a healthy system with zero errors.

Vigilmon, by contrast, detects the outage immediately. The probe fails. The alert fires. Your team knows within one check interval.

| Scenario | Airbrake sees | Vigilmon sees | |---|---|---| | Unhandled exception in application | ✅ Full stack trace | ✅ HTTP 500 from probe | | Server unreachable (full outage) | ❌ Nothing | ✅ Probe fails, alert fires | | DNS resolution failure | ❌ Nothing | ✅ Probe fails, alert fires | | TLS certificate expired | ❌ Nothing | ✅ Probe fails, alert fires | | Load balancer returning 502 | ❌ Nothing | ✅ Detects 502, alert fires | | Slow database causing timeouts | ✅ Performance traces | ✅ Response time exceeds threshold | | Cron job stopped running | ❌ | ✅ Heartbeat missed, alert fires |

Feature Comparison

| Feature | Airbrake | Vigilmon | |---|---|---| | Error capture with stack traces | ✅ core strength | ❌ | | Performance monitoring (APM) | ✅ | ❌ | | Deploy tracking / regression tagging | ✅ | ❌ | | External HTTP uptime probing | ❌ | ✅ core strength | | Multi-region consensus probing | ❌ | ✅ default behavior | | TCP port monitoring | ❌ | ✅ | | Cron job heartbeat monitoring | ❌ | ✅ | | Customer-facing status page | ❌ | ✅ included | | Alerting on complete outage | ❌ | ✅ | | Requires code/SDK changes | ✅ SDK required | ❌ zero code changes | | Setup time | 15–30 min (SDK + config) | ~2 minutes |

The Complementary Stack

The right framing is not "Airbrake vs Vigilmon" — it is "Airbrake and Vigilmon at different layers."

┌─────────────────────────────────────────────┐
│  LAYER 1: Is the service reachable at all?   │
│  → Vigilmon (external probes, uptime)        │
├─────────────────────────────────────────────┤
│  LAYER 2: Is the service throwing errors?    │
│  → Airbrake (exception tracking, APM)        │
├─────────────────────────────────────────────┤
│  LAYER 3: Is the service performing well?    │
│  → Airbrake APM or Prometheus + Grafana      │
└─────────────────────────────────────────────┘

Each layer catches what the others miss:

Vigilmon fires, Airbrake silent → the service is completely unreachable. The problem is at the infrastructure layer (network, DNS, load balancer, server). Airbrake SDK has no process to report from. Vigilmon caught the worst possible failure.
Airbrake fires, Vigilmon silent → the service is reachable and returning successful responses to probes, but throwing exceptions internally for specific users, request patterns, or edge cases. Airbrake caught a bug that wasn't visible externally.
Both fire → the service is up but returning error status codes. The probe detects the HTTP 500. Airbrake provides the stack trace. You have both the scope and the diagnosis.

Teams relying on Airbrake alone for alerting have a complete blind spot for the entire Layer 1 failure class — the failures users care about most.

The Detection Gap Problem

Consider this sequence during a full outage:

Your server loses network connectivity
Users attempt to load your application — requests time out
Users see a browser error or timeout page
Airbrake SDK — whether client-side or server-side — has nothing to report
No exception is thrown, so no alert fires
Your team gets no notification
Users start tweeting, filing support tickets, or quietly leaving

With Vigilmon configured:

Probe fires on its regular interval (every 1 minute)
Request times out — multiple probe regions confirm
Alert fires to Slack/email/webhook within 1–2 minutes
Your team is investigating before users start filing tickets

This is the detection gap: the time between when users experience a failure and when your engineering team knows. For full-outage scenarios, Airbrake's detection gap is unbounded — it never fires. Vigilmon's detection gap is bounded by the probe interval.

Setting Up Both

Running Vigilmon and Airbrake together requires no integration between them — they observe independently and alert independently.

Vigilmon setup (2 minutes)

1. Create a free account at vigilmon.online
2. Click "Add Monitor" → enter your API or app URL
3. Set check interval: 1 minute
4. Add Slack webhook or email for alerts
5. Optionally: ping a heartbeat URL from your cron jobs

Airbrake SDK setup (Node.js example)

const Airbrake = require('@airbrake/node');

const airbrake = new Airbrake.Notifier({
  projectId: process.env.AIRBRAKE_PROJECT_ID,
  projectKey: process.env.AIRBRAKE_API_KEY,
  environment: process.env.NODE_ENV,
});

// Wrap your app to capture unhandled rejections
process.on('unhandledRejection', (reason) => {
  airbrake.notify(reason);
});

With both configured, your alert coverage is complete:

Vigilmon fires → service is unreachable → investigate infrastructure immediately
Airbrake fires → service is reachable but throwing exceptions → investigate code
Both fire → service is up but returning errors → you have scope and stack trace

When to Prioritize Each Tool

Most teams should run both. But if you're starting with one:

Start with Vigilmon if:

You have no monitoring at all and need coverage in under 5 minutes
You've been burned by outages where users discovered the problem before you did
You need a customer-facing status page for transparency
You're monitoring third-party APIs, webhooks, or services where SDK installation isn't possible

Start with Airbrake if:

Your infrastructure is stable but you're shipping code bugs that crash the app
You need detailed debugging context (stack traces, user info, breadcrumbs) when things go wrong
You want to track error regressions across deploys
You have complex application logic where silent failures in code are a primary risk

The combination handles both failure classes. The free tiers of both tools are sufficient for most small teams. There is no scenario where having both creates a problem — and there are many scenarios where having only one leaves your team blind.

Pricing Overview

| | Airbrake | Vigilmon | |---|---|---| | Free tier | Limited trial | 5 monitors, 1-min intervals, status page | | Entry paid | ~$19/month | ~$10–20/month | | Self-hosted | ❌ | ✅ open source |

Vigilmon's free tier is genuinely useful indefinitely — no trial period, no credit card required. Airbrake's free access is typically trial-based before requiring a paid plan.

Summary

Airbrake and Vigilmon are complementary monitoring tools, not competitors. They are looking at your system from opposite directions.

Airbrake catches what goes wrong inside your application: exceptions, regressions, and performance bottlenecks that your code generates. If a bug exists and code runs, Airbrake will find it.

Vigilmon catches when your application stops being reachable: server outages, DNS failures, expired certificates, and network issues that produce no exceptions because no code runs at all.

The monitoring blind spot for teams using only Airbrake is exactly the failure type users care most about — complete unavailability. Vigilmon closes that gap.

Add external uptime monitoring to your stack at vigilmon.online — 5 monitors, 1-minute check intervals, multi-region consensus, and a status page, all free. Set up in 2 minutes, no code changes required.

Tags: #monitoring #devops #airbrake #uptime #errortracking #sre #observability