Free SSL/TLS Certificate Expiry Checker

Nginx (Certbot auto-renewal)

server {
    listen 443 ssl http2;
    server_name example.com;

    ssl_certificate     /etc/letsencrypt/live/example.com/fullchain.pem;
    ssl_certificate_key /etc/letsencrypt/live/example.com/privkey.pem;

    ssl_stapling on;
    ssl_stapling_verify on;
    ssl_trusted_certificate /etc/letsencrypt/live/example.com/chain.pem;
}

# /etc/cron.d/certbot
0 3 * * * root certbot renew --quiet --deploy-hook "systemctl reload nginx"

Apache (Certbot auto-renewal)

<VirtualHost *:443>
    ServerName example.com

    SSLEngine on
    SSLCertificateFile      /etc/letsencrypt/live/example.com/fullchain.pem
    SSLCertificateKeyFile   /etc/letsencrypt/live/example.com/privkey.pem

    SSLUseStapling on
    SSLStaplingResponderTimeout 5
</VirtualHost>

# /etc/cron.d/certbot
0 3 * * * root certbot renew --quiet --deploy-hook "systemctl reload apache2"

Node.js (greenlock-express for ACME)

import GreenlockExpress from "greenlock-express"
import express from "express"

const app = express()
app.get("/", (_req, res) => res.send("ok"))

GreenlockExpress.init({
  packageRoot: process.cwd(),
  configDir: "./greenlock.d",
  maintainerEmail: "ops@example.com",
  cluster: false,
})
  .ready((glx) => glx.serveApp(app))
// Certificates auto-renew ~30 days before expiry via the ACME client.