The benefits of Let’s Encrypt certificates are that they are automated, short lifetimes (90 days) and that they are completely FREE!

Below is a quick guide on how to install Let’s Encrypt SSL on a Synology NAS!

Prerequisites before starting

  • A domain name of your own
  • DDNS service configured. I’ll be using the Synology DDNS service as it’s free and I already use it.
  • Create a CNAME DNS record with your registrar to forward requests to your DDNS service.
  • Enable port forwarding of from your router for port 80 to your NAS.

How to install a Let’s Encrypt SSL on a Synology NAS

For this guide I’ll be using my Synology DS1815+ running DSM 6.1.5-15254 Update 1 with 16GB RAM.

  1. First log into your DSM and navigate to: Control panel > Security > Certificate and click on  
  2. Then select “Replace an existing certificate” to replace your existing or self-signed certificate.   
  3. Now select “Get a certificate from Let’s Encrypt” and check “Set as default certificate”   
  4. Finally, enter a Domain Name and email address and click on Apply.   At this point your Synology NAS will receive the Let’s Encrypt SSL and restart it’s web services automatically and you’ll then be able to access your NAS via the domain name.
    Every 90 days your Synology will automatically renew the Let’s Encrypt SSL cert for you.