🔒 Monitor SSL certificate expiry with Google Sheets and SMTP email alerts
⚡ 98 views · 🔒 SecOps & Security Automation
Description
Who is this for?
DevOps engineers, sysadmins, and website owners who manage multiple domains and need proactive SSL certificate expiration monitoring without manual checks.
What it does
Automatically monitors SSL certificates across multiple domains, tracks expiration status in a Google Sheet dashboard, and sends beautifully formatted HTML email alerts before certificates expire.
✅ No API rate limits — Uses direct OpenSSL commands, so you can scan unlimited domains with zero API costs or restrictions.
How it works
- Triggers on schedule (every 3 days at 10AM)
- Reads domain list from your Google Sheet
- Checks each domain’s SSL certificate using OpenSSL commands
- Parses expiration dates, issuer info, and calculates days remaining
- Updates Google Sheet with current status for all domains
- Sends styled email alerts only when certificates are expiring soon
Set up steps
- Connect your Google Sheets OAuth2 credentials
- Create a Google Sheet with these columns: Domain, Expiry Date, Days Left, Status, Issuer, Last Checked (the workflow matches on the Domain column to update results)
- Add your domains to scan in the Domain column
- Update the Sheet ID in the Read Domain List from Google Sheets and Update Google Sheet with Results nodes
- Connect SMTP credentials in the Send Alert Email via SMTP node
- Optionally adjust
ALERT_THRESHOLD_DAYSin two nodes: Prepare Domain List and Set Threshold and Parse SSL Results and Identify Expiring Certs (default: 20 days)
Setup time: ~10 minutes
🔗 Nodes Used
Send Email, Google Sheets, Schedule Trigger
📥 Import
Download workflow.json and import into n8n:
Workflow menu → Import from File