How do I set up recurring crawls for site monitoring?

To set up recurring crawls for site monitoring, you generally want a system that:

1. Crawls your site on a schedule
2. Compares each crawl to previous runs
3. Alerts you when something changes or breaks

Here’s a practical way to do it.

1) Define what you want to monitor

Decide which pages and issues matter most:

• Key pages: homepage, product pages, pricing, docs, login, etc.
• Technical issues: 404s, 500s, redirects, noindex tags, broken links
• Content changes: title, meta description, H1, body text
• Performance or availability: response time, downtime

2) Choose a crawling approach

Common options:

A. Use an SEO/site monitoring tool

Many tools support scheduled crawls out of the box:

• Screaming Frog SEO Spider + scheduled mode
• Sitebulb
• Ahrefs / Semrush site audit
• ContentKing (continuous monitoring)

These are easiest if you want dashboards and alerts without building your own.

B. Build your own scheduled crawler

If you need custom monitoring, use:

• A crawler library: Scrapy, Playwright, Puppeteer, BeautifulSoup + requests
• A scheduler: cron, Celery, Airflow, GitHub Actions, Cloud Scheduler
• Storage: database, S3, CSV, or a data warehouse

3) Set up the crawl schedule

Examples:

Cron example

Run every night at 2 AM:

0 2 * * * /usr/bin/python3 /path/to/crawl.py

GitHub Actions example

For lightweight monitoring:

on:
  schedule:
    - cron: "0 2 * * *"

Cloud scheduler

If deployed in cloud:

• AWS EventBridge
• Google Cloud Scheduler
• Azure Scheduler / Logic Apps

4) Store crawl results

Save enough data to compare runs:

• URL
• HTTP status code
• Title tag
• Meta description
• Canonical
• H1
• Word count
• Last crawl timestamp
• Response time
• Extracted links

A database table or JSON snapshots works well.

5) Compare against previous crawl

Look for:

• New 404/500 pages
• Missing pages
• Changes in titles/H1s
• New redirects
• Pages removed from crawl
• Robots/noindex changes
• Sudden drops in word count or content changes

6) Add alerting

Notify yourself when thresholds are exceeded:

• Email
• Slack
• Teams
• PagerDuty
• Webhook

Example alerts:

• “10 pages now return 404”
• “Homepage title changed”
• “Crawl found 200 new broken internal links”

7) Respect crawl limits

To avoid overloading your site:

• Set low concurrency
• Add delays between requests
• Respect robots.txt if appropriate
• Exclude irrelevant sections (admin, search results, logout)
• Limit crawl depth if needed

8) Good monitoring setup checklist

A solid recurring crawl setup usually includes:

• Scheduled runs
• Same settings every time
• Consistent crawl scope
• Change detection
• Alerting
• Historical reporting

Simple example architecture

• Crawler: Scrapy or Screaming Frog CLI
• Scheduler: cron
• Storage: PostgreSQL or JSON files
• Diffing: Python script comparing current vs previous crawl
• Alerts: Slack/email

If you want, I can also give you:

1. a no-code setup using an existing tool, or
2. a Python example for a custom scheduled crawler.