Monitoring n8n with Vigilmon: Health Endpoint, Web Editor Uptime, Webhook TCP Check & SSL Alerts

n8n is the open-source workflow automation platform that connects your SaaS tools, internal APIs, and databases through a visual editor — replacing Zapier and Make with a self-hosted instance you fully control. Because n8n workflows execute business processes automatically (syncing CRMs, sending notifications, processing orders, triggering deployments), availability is not optional: if n8n goes down, workflows stop silently. If the webhook endpoint stops responding, incoming triggers from Stripe, GitHub, or your own services fail without retrying. If the web editor becomes unreachable, your team can't diagnose or fix broken workflows. Vigilmon gives you external visibility into n8n's health API, web editor, webhook TCP endpoint, and SSL certificate so your automation layer is never silently failing.

What You'll Build

• A monitor on n8n's /healthz health endpoint
• An HTTP monitor for the n8n web editor UI
• A TCP monitor for the webhook execution port
• SSL certificate monitoring for your n8n domain
• An alerting setup that distinguishes editor failures from webhook delivery failures

Prerequisites

• A running n8n instance with a public or network-reachable domain
• HTTPS configured (e.g., https://n8n.example.com)
• Webhook port accessible (default 5678, or 443/80 behind a reverse proxy)
• A free account at vigilmon.online

Step 1: Verify n8n's Health Endpoint

n8n exposes a dedicated health check at /healthz:

curl https://n8n.example.com/healthz

A healthy n8n returns HTTP 200 with a JSON body:

{"status":"ok"}

This endpoint is unauthenticated and specifically designed for uptime monitoring — it confirms that the n8n process is running and its core services are operational, including database connectivity and queue worker availability.

Step 2: Create a Vigilmon HTTP Monitor for the Health Endpoint

1. Log in to Vigilmon → Add Monitor → HTTP.
2. URL: https://n8n.example.com/healthz.
3. Check interval: 60 seconds.
4. Response timeout: 10 seconds.
5. Expected status: 200.
6. Keyword: ok.
7. Click Save.

This monitor catches:

• n8n process crashes or unexpected restarts
• Database connectivity failures (n8n stores workflow state and execution history in its database)
• Queue worker failures in scaled deployments
• Configuration errors after n8n upgrades or environment variable changes

Because n8n workflows often execute business-critical processes, a 60-second check interval ensures you're alerted within a minute of the automation layer going offline — before stakeholders notice that orders aren't being processed or notifications aren't being sent.

Step 3: Monitor the n8n Web Editor

The /healthz endpoint confirms the backend is alive, but the web editor involves additional layers: the Vue.js frontend, authentication middleware, and the WebSocket connections that power live execution logs. Monitor the editor independently:

1. Add Monitor → HTTP.
2. URL: https://n8n.example.com.
3. Check interval: 60 seconds.
4. Expected status: 200.
5. Keyword: n8n.
6. Label: n8n Web Editor.
7. Click Save.

This monitor catches reverse proxy failures, TLS termination issues, and static asset serving problems that wouldn't affect the health endpoint but would prevent your team from accessing the editor to diagnose workflow failures.

Note: If your n8n instance uses basic auth or SSO, the web editor monitor will see the login page rather than the editor itself. Adjust the keyword to match text that appears on your login page (e.g., n8n.io) to keep the monitor accurate.

Step 4: Create a TCP Monitor for the Webhook Port

n8n's webhook execution endpoint receives incoming triggers from external services. Even if n8n's UI is healthy, a firewall change or reverse proxy misconfiguration can silently drop webhook traffic — breaking integrations without any visible error in the n8n interface.

1. Add Monitor → TCP.
2. Host: n8n.example.com.
3. Port: 443 (if behind a reverse proxy) or 5678 (n8n's default port if directly exposed).
4. Check interval: 60 seconds.
5. Response timeout: 10 seconds.
6. Label: n8n Webhook Port.
7. Click Save.

When the TCP monitor fires but the web editor monitor is green, you have a network routing issue specifically affecting webhook ingress — n8n is running but external services cannot reach it to trigger workflows. This is a common scenario after reverse proxy reconfigurations or firewall rule changes.

Security note: n8n's default port 5678 should not be directly exposed to the public internet. Use a reverse proxy (nginx, Caddy) and monitor port 443 instead. The TCP check on 443 confirms your reverse proxy is accepting connections even when the full HTTP response isn't being verified.

Step 5: Monitor SSL Certificates

n8n's SSL certificate is critical because:

• The web editor uses HTTPS — expiry locks out your team
• Webhook endpoints use HTTPS — expiry causes external services to reject the connection and stop triggering workflows
• n8n's credential storage and OAuth callbacks require HTTPS — expiry breaks API integrations at renewal time

1. Add Monitor → SSL Certificate.
2. Domain: n8n.example.com.
3. Alert when expiry is within: 30 days.
4. Alert again: 14 days, 7 days, 3 days, 1 day.
5. Click Save.

For workflow automation platforms, catching certificate expiry at 30 days is especially important because many webhook sources (Stripe, GitHub, Salesforce) will immediately stop delivering events when they encounter a certificate error — and resume delivery requires reconfiguring webhooks on the external service, not just renewing the certificate.

Step 6: Configure Alerting

In Vigilmon under Settings → Notifications, configure your alert channels:

| Monitor | Trigger | Action | |---|---|---| | /healthz | Non-200 or ok missing | Check systemctl status n8n; inspect n8n process logs | | Web Editor | Non-200 or n8n missing | Check reverse proxy; verify n8n frontend assets are serving | | Webhook TCP port | Connection refused or timeout | Check firewall rules; inspect reverse proxy configuration | | SSL certificate | < 30 days to expiry | Renew certificate; check ACME automation on reverse proxy |

Alert after: 2 consecutive failures for HTTP monitors. 1 failure for the TCP monitor — webhook port connection failures are rarely transient and indicate a real routing problem.

Common n8n Failure Modes and What Vigilmon Catches

| Scenario | Vigilmon monitor | |---|---| | n8n process crash | /healthz unreachable; alert within 60 s | | Database goes down | Health check returns non-200; workflow execution history unavailable | | Webhook port blocked by firewall | TCP monitor fires; web editor monitor stays green | | Reverse proxy misconfiguration | Web editor monitor fires; /healthz may be unreachable | | SSL certificate expires | SSL monitor alerts at 30-day threshold; webhooks stop delivering | | n8n upgrade failure | Health check non-200 or missing keyword; rollback needed | | Queue worker crashes (scaled mode) | Health check may degrade; workflow executions queue but don't run | | Out of memory | n8n process restarts; health check temporarily unreachable | | DNS misconfiguration | All HTTP and SSL monitors fire simultaneously | | n8n license/community edition limits | Health check stays green; specific workflows silently disabled |

Workflow automation is invisible infrastructure — it works until it doesn't, and when it fails, the impact shows up in downstream business processes, not in error logs your team checks. Vigilmon watches n8n's health endpoint, web editor, webhook port, and SSL certificate so you know immediately when your automation layer needs attention, before your users notice that something is broken.

Start monitoring n8n in under 5 minutes — register free at vigilmon.online.