tutorial

How to Monitor ONLYOFFICE with Vigilmon (Document Server, API, and SSL Alerts)

ONLYOFFICE Docs and ONLYOFFICE Workspace give teams a self-hosted alternative to Google Docs — real-time collaborative editing for text, spreadsheets, and pr...

ONLYOFFICE Docs and ONLYOFFICE Workspace give teams a self-hosted alternative to Google Docs — real-time collaborative editing for text, spreadsheets, and presentations without sending documents to a third-party cloud. When ONLYOFFICE goes down, editing sessions drop and users can't open or save documents, often mid-collaboration. Silent failures are common: the web UI may still load while the document conversion service or WebSocket layer is broken.

This tutorial covers end-to-end monitoring for ONLYOFFICE using Vigilmon — free tier, no credit card.

Why ONLYOFFICE needs dedicated monitoring

ONLYOFFICE has multiple independent services that can fail in isolation:

  • Document Server (DocService) — the core editing engine that handles WebSocket connections and document conversion; can fail while nginx still serves the portal UI
  • Conversion service — handles document format conversions (DOCX to PDF, etc.); a separate process that can crash independently
  • Database connectivity — ONLYOFFICE Workspace requires PostgreSQL and Redis; a database failure causes editing to fail silently (documents appear to save but changes are lost)
  • SSL certificate expiry — breaks HTTPS WebSocket connections that the collaborative editor depends on, causing editing sessions to drop

External monitoring from Vigilmon catches these from the outside — the same way your users experience failures.

What you'll need

  • A running ONLYOFFICE Docs or ONLYOFFICE Workspace installation
  • A free Vigilmon account (takes under a minute to sign up)

Step 1: Verify the Document Server health endpoint

ONLYOFFICE Document Server exposes a dedicated health check endpoint:

curl -i https://onlyoffice.your-domain.com/healthcheck

When the Document Server is healthy, it returns:

HTTP/2 200
content-type: text/plain

true

The response body is the literal string true. Any other response — including false, a 500 error, or a timeout — indicates the Document Server is unhealthy.

If you're running ONLYOFFICE Workspace (the full portal), the health check path is the same but served from the Document Server's virtual host, not the portal's main domain.

Step 2: Set up HTTP monitoring for the Document Server

  1. Log in to vigilmon.online and go to Monitors → New Monitor
  2. Choose HTTP / HTTPS
  3. URL: https://onlyoffice.your-domain.com/healthcheck
  4. Check interval: 1 minute
  5. Expected status code: 200
  6. Response body contains: true
  7. Save the monitor

This is the most important monitor — it directly verifies that the document editing engine is running and ready to accept connections.

Step 3: Monitor the web portal UI

Add a separate monitor for the main portal or welcome page:

  1. Monitors → New Monitor → HTTP / HTTPS
  2. URL: https://onlyoffice.your-domain.com/
  3. Check interval: 2 minutes
  4. Expected status code: 200
  5. (Optional) Response body contains: ONLYOFFICE
  6. Save

This catches nginx failures, portal application crashes, and misconfigured reverse proxy rules that would prevent users from reaching the application at all.

Step 4: Monitor the Document Server API

ONLYOFFICE Document Server exposes a JSON API for document management. The API info endpoint is a lightweight check that validates API routing:

curl -i https://onlyoffice.your-domain.com/info/info.json

Set up a monitor for this path:

  1. Monitors → New Monitor → HTTP / HTTPS
  2. URL: https://onlyoffice.your-domain.com/info/info.json
  3. Check interval: 5 minutes
  4. Expected status code: 200
  5. Response body contains: documentServer
  6. Save

If the conversion service or internal document processing fails, this endpoint will return an error or degraded status before the /healthcheck endpoint does, giving you earlier warning.

Step 5: Set up SSL certificate monitoring

ONLYOFFICE's collaborative editing relies on WebSocket connections over WSS (WebSocket Secure), which require a valid SSL certificate. If the certificate expires, editing sessions drop and new connections fail with cryptic browser errors — users won't know it's a certificate issue.

  1. Monitors → New Monitor → SSL Certificate
  2. Domain: onlyoffice.your-domain.com
  3. Alert at 30 days before expiry
  4. Critical alert at 7 days before expiry
  5. Save

If you're using Let's Encrypt with Certbot or ONLYOFFICE's built-in certificate manager, also verify your auto-renewal cron job is working — certificate monitoring is a safety net, not a replacement for working renewal.

Step 6: Configure response time monitoring

ONLYOFFICE document opening involves multiple backend hops — database queries, file storage reads, and WebSocket setup. A response time above 5 seconds for the health endpoint is a leading indicator of database or storage backend issues.

  1. Open the /healthcheck HTTP monitor
  2. Settings → Response Time Alert
  3. Threshold: 5000ms
  4. Save

This gives you an early warning before users start reporting that documents take forever to open.

Step 7: Set up alert channels

  1. Alert Channels → Add Channel
  2. Configure Email for the primary alert contact
  3. Configure Slack or Discord for team alerts
  4. Assign all monitors to the alert channel

For ONLYOFFICE deployments in business environments, email alerts to an operations alias (e.g. ops@your-company.com) ensure the right people are notified even if a specific on-call engineer is unavailable.

Step 8: Create an internal status page

  1. Status Pages → New Status Page
  2. Name: "ONLYOFFICE Status"
  3. Add monitors: Document Server health, web portal UI, API info
  4. Publish

Share the status page URL with your team. When ONLYOFFICE has issues, users can check the status page themselves instead of creating support tickets.

Monitor summary

| Monitor | Type | Interval | What it catches | |---------|------|----------|-----------------| | /healthcheck | HTTP | 1 min | Document Server crashes, service failures | | / portal UI | HTTP | 2 min | nginx failures, portal application crashes | | /info/info.json | HTTP | 5 min | API routing, conversion service health | | SSL certificate | SSL | Daily | Certificate expiry, WSS failures | | Response time > 5s | Threshold | — | Database or storage backend issues |

What's next

  • Heartbeat monitoring — if you run scheduled document backup or export jobs, add heartbeat monitors to detect silent job failures
  • Multi-service status page — if you run ONLYOFFICE alongside other self-hosted tools, combine them on a single status page for a unified view

Get started free at vigilmon.online — no credit card, monitors are live in under a minute.

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