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doc/security/ssl-certbot.md

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+# Generate a Certificate Using Let's Encrypt 🔒
+
+To get around the certificate warnings in Chrome, you might want to install a
+certificate from a trusted Certificate Authority (CA). Luckily, there are CAs
+like [Let's Encrypt](lets-encrypt) which provide certificates for free.
+
+[lets-encrypt]: https://letsencrypt.org/
+
+---
+
+### Using Certbot
+
+[Certbot](certbot) is the program we'll be using to issue certificates from
+Let's Encrypt.
+
+> Pre-requisites: You will need a domain name or subdomain pointed to the IP
+> address of your server.
+
+1. Install Certbot by heading to the [instructions page](certbot-instructions).
+   Select **None of the above** for the software and the right operating system
+   for your setup.
+2. Follow the installation instructions, and stop once you get up to the part
+   where you run the `certbot certonly` command.
+3. Ensure your code-server instance isn't running, and any other webservers that
+   could interfere are also stopped.
+4. Run the following command, replacing `code.example.com` with the
+   hostname/domain you want to run your server on, to issue a certificate:
+   ```
+   sudo certbot certonly --standalone -d code.example.com
+   ```
+5. Follow the prompts, providing your email address and accepting the terms
+   where required.
+6. Once the process is complete, it should print the paths to the certificates
+   and keys that were generated. You can now restart any webservers you stopped
+   in step 2.
+
+[certbot]: https://certbot.eff.org/
+[certbot-instructions]: https://certbot.eff.org/instructions
+
+---
+
+### Starting code-server with a Certificate and Key
+
+Just add the `--cert` and `--cert-key` flags when you run code-server:
+
+```shell
+./code-server --cert=/etc/letsencrypt/live/code.example.com/fullchain.pem --cert-key=/etc/letsencrypt/live/code.example.com/privkey.pem
+```
+
+You can now verify that your SSL installation is working properly by checking
+your site with [SSL Labs' SSL Test](ssl-labs-test).
+
+[ssl-labs-test]: https://www.ssllabs.com/ssltest/
+
+---
+
+### Next Steps
+
+You probably want to setup automatic renewal of your certificates, as they
+expire every 3 months. You can find instructions on how to do this in
+[Certbot's documentation](certbot-renew-docs).
+
+[certbot-renew-docs]: https://certbot.eff.org/docs/using.html?highlight=hooks#renewing-certificates