Synology ssl certificate

Welcome to the Latest Installment of My Synology Series

In this comprehensive guide, we’re diving into the world of Synology once again, focusing on a crucial aspect: installing an SSL certificate for your Synology NAS. Whether you’ve arrived here following my previous article “Synology on WordPress” or “Optimize WordPress on Synology,” or you’re just starting your journey into enhancing your Synology setup, you’re in the right place.

This article aims to bridge the gap between these topics, providing you with a seamless learning experience. So, let’s get started on ensuring your Synology NAS is secure and fully optimized.


Introduction to Setting Up an SSL Certificate on Your Synology NAS

Securing Your Synology NAS with an SSL Certificate

Keeping your Synology NAS secure is crucial to protect your data from unauthorized access, and an SSL (Secure Socket Layer) certificate plays a key role in this. When you set up an SSL certificate, it involves handling several SSL files. These include the certificate itself, the private key, and often intermediate certificates, which establish a trust chain to a root certificate.

By default, your Synology NAS is designed to facilitate the SSL activation process. The NAS interface guides you through downloading the necessary SSL files from a certificate authority like Let’s Encrypt.


Why Choose Let’s Encrypt for Your NAS?

Let’s Encrypt is widely respected for enhancing NAS security without any cost. It stands apart from traditional providers who charge for SSL certificates. As a non-profit, Let’s Encrypt offers these certificates for free, promoting a safer internet for everyone.

Their certificates are as secure as the paid ones, which is essential in an online world where insecure websites are not trusted, are recognized by most web browsers, and are easy to set up, especially on Synology NAS. These devices come with built-in Let’s Encrypt integration, making the process straightforward for administrators who value security and cost-effectiveness.

A standout feature of Let’s Encrypt is the automated renewal of certificates. This means less hassle for you, as your Synology NAS can handle the renewals. It ensures uninterrupted, secure access to your NAS without constant manual updates.

Given its user-friendly approach and robust security, Let’s Encrypt is an excellent choice for your Synology NAS.


Preparing Your Synology NAS for SSL Installation

Setting Up a Custom Domain for Your Synology NAS

The First Step is getting a Custom Domain Name

Before installing an SSL certificate, having a custom domain name like werdernet.com for your Synology NAS is essential. Think of this domain name as your NAS’s unique online address. If you haven’t already got one, you can register a domain name through various third-party providers. I recommend Namecheap.

Synology’s Easy-to-Use DDNS Service

Synology simplifies remote access to your NAS with its Dynamic Domain Name System (DDNS) service. This service assigns a Synology-specific domain name, like “your name. Synology.me”, to your NAS. It’s particularly useful if your home internet has a dynamic IP address, which changes periodically.

Quickconnect is not required. With your custom domain (hostname) your Synology NAS will have the ability for external access as well. You would need the correct port forwarding in place.

Unlike traditional domain names that require frequent manual updating with changing IP addresses, Synology’s DDNS service automatically updates this for you. So, even if your IP address changes, your custom Synology domain will consistently point to your NAS. This automatic update feature makes Synology’s DDNS a good choice.

You find it Synology DSM, under external access, DDNS.


Synology DDNS

Connecting Your Custom Domain to Your Synology NAS

After securing your domain name, the next crucial step is linking it to your Synology NAS. You must direct the domain to your NAS’s external or WAN IP address. This connection is essential for ensuring your NAS is accurately accessible via your chosen domain on the internet.

If your IP address is dynamic, which is very common with most home internet connections, you might consider using a service like Dynu.com. Dynu.com is highly regarded for efficiently mapping dynamic IP addresses to domain names. Even if your IP address changes, Dynu.com will keep your domain consistently pointing to your NAS.

This step is fundamental, especially when setting up your SSL certificate. The SSL certificate must be linked to your domain, which is connected to your NAS. This linkage enables secure and encrypted communication between your NAS and its users.

An important step is to point the DNS nameserver to the DDNS service. You perform this task at the provider where you bought your custom domain name.

Here is a screenshot from Namecheap on changing the DNS server to another provider.


Namecheap domain service

Setting Up Port Forwarding: A Crucial Step for SSL Installation

Before installing your SSL certificate with Let’s Encrypt, setting up port forwarding on your Synology NAS is crucial. Specifically, you need to forward ports 80 and 443. Port 80 is used for HTTP connections, and port 443 for HTTPS, which is secured by SSL. This setup is crucial because Let’s Encrypt verifies your domain’s ownership and issues the SSL certificate through these ports. By forwarding them, you ensure that Let’s Encrypt can communicate with your NAS during the verification and installation process, enabling a smooth and successful setup of your SSL certificate for secure, encrypted web access.


Installing a Let’s Encrypt SSL Certificate on Your Synology NAS

Getting started with Let’s Encrypt on your Synology NAS is a straightforward process. This section will guide you through installing a Let’s Encrypt SSL certificate, enhancing your NAS’s security with minimal hassle. The Synology SSL services setup wizard makes it straightforward.

Follow along for a quick and easy setup:

  1. Access DSM Control Panel: Log into your Synology DiskStation Manager (DSM).
  2. Navigate to Security Settings: Go to the ‘Control Panel’, and under the ‘Security’ tab, find the ‘Certificate’ section.
  3. Add a New Certificate: Click on ‘Add’ and then select ‘Add a new certificate’. Choose ‘Get a certificate from Let’s Encrypt’.

create SSL certification
Get a new SSL certificate from Let's Encrypt

  • Domain Name: Enter the domain name you’ve registered and pointed to your NAS.
  • Email Address: Provide an email address for certificate registration and recovery.
  • Subject Alternative Name (SAN): Add your custom domain name. An email account is important for any notifications. For a wildcard certificate, use the format *.yourdomain.com. Ensure your DNS settings support wildcard subdomains if you go this route.

enter SSL information

  1. Begin Validation Process: After entering the details, start the validation process. Let’s Encrypt do the domain validation for you.
  2. Automatic Installation: Let’s Encrypt will issue the SSL certificate to your NAS once the domain is validated. The DSM will automatically install and activate it.
  3. Confirm Certificate Activation: You should see the certificate in the ‘Certificate’ section once installed. Ensure it’s the default for DSM and any other services you run on your NAS.

Synology SSL certificate installed

Verifying and Managing Your New SSL Certificate

Testing HTTPS Access to Your Synology NAS

Once your Let’s Encrypt SSL certificate is installed, it’s crucial to test it:

  1. Open a Web Browser: Use any web browser and enter your Synology NAS domain name.
  2. Check the URL Bar: Look for ‘HTTPS’ before your domain name. It indicates a secure connection.
SSL Padlock

  1. Browser Security Icon: Most browsers show a padlock icon for secure HTTPS connections. Ensure this is present.
  2. Test Services: If your NAS hosts other services (like a personal website), navigate to those to confirm they’re secure.

This test ensures that your SSL certificate works correctly and your NAS is securely accessible online.


Renewing the Certificate

Let’s Encrypt certificates have a 90-day validity period. Thankfully, your Synology NAS can automatically renew these certificates:

  1. Automatic Renewal: Synology DSM is configured to renew Let’s Encrypt certificates automatically. This process happens every 90 days, ensuring no service interruption due to an expired certificate.
  2. Check Renewal Settings: In DSM, you can verify the auto-renewal settings under the ‘Certificate’ section in the ‘Security’ tab.
Synology check settings
  1. Manual Renewal Option: You can manually renew the certificate by selecting it in the ‘Certificate’ section and clicking ‘Renew’.
Manually renew certificate
  1. Notification: Synology will typically notify you via DSM notifications if there’s an issue with the automatic renewal.

This automatic renewal process helps maintain continuous secure access to your Synology NAS without regular manual intervention.


Configure the certificate for Applications

Using the settings button, two SSL certificates in my Synology NAS can be allocated to specific applications. However, the service names lack clarity. I configure the system default and replication service, which works for my web server. I would have wished to see the application names like File Station, Web Station, etc.

Assign the SSL certificate to an application

What Should I Do If I Encounter Errors Installing or Renewing My Let’s Encrypt SSL Certificate on Synology NAS?

If you face issues while installing or renewing your Let’s Encrypt SSL certificate on your Synology NAS, here are some steps to troubleshoot:

  1. Check Domain Configuration: Ensure your domain name correctly points to your NAS’s IP address. Any misconfiguration here can lead to validation failures.
  2. Verify Port Forwarding: Confirm that ports 80 and 443 are correctly forwarded in your router settings. These ports are essential for Let’s Encrypt’s validation process.
  3. Review DSM Version: Make sure your Synology DSM is up-to-date. Older versions might have compatibility issues or bugs resolved in newer releases.
  4. Check for Firewall Restrictions: Ensure no firewall settings block the ports necessary for Let’s Encrypt to validate your domain.
  5. Review Let’s Encrypt Rate Limits: Let’s Encrypt has rate limits for certificate requests. If you’ve hit a limit, you may need to wait before trying again.
  6. Consult Synology Support and Forums: If you’re still experiencing issues, check Synology’s support resources or community forums. Often, other users have faced similar issues and can offer practical solutions.
  7. Check Let’s Encrypt Status: Sometimes, the issue might be on Let’s Encrypt’s end. Check their status page for any ongoing problems or maintenance.

FAQs on Synology SSL Certificate Setup with Letsencrypt

Which Models of Synology NAS Support SSL Certificates?

Most Synology NAS models support SSL certificates. However, it’s always best to check the specific model on Synology’s official website or refer to the documentation of your NAS model for confirmation. Generally, any Synology NAS running DSM (DiskStation Manager) 6.0 or later should support SSL certificates, including Let’s Encrypt.

How Often Should I Renew My Let’s Encrypt SSL Certificate?

Let’s Encrypt SSL certificates, which have a validity period of 90 days. Synology NAS is designed to automatically renew these certificates before they expire, typically starting the renewal process 30 days before the expiration date. Ensuring that your Synology NAS is configured correctly for auto-renewal is essential to maintain continuous security.

What Are the Benefits of Using Let’s Encrypt Over Other Certification Authorities?

Cost-Effectiveness: Let’s Encrypt offers SSL certificates for free, making it an excellent option for individuals and organizations looking to secure their websites without incurring additional costs.
Ease of Use: Let’s Encrypt is designed to simplify obtaining, installing, and renewing SSL certificates. Its integration with Synology NAS makes it particularly user-friendly.
Automation: The automatic renewal feature of Let’s Encrypt minimizes the need for manual certificate management, reducing the risk of running a service with an expired certificate.
Security: Let’s Encrypt certificates offer the same level of encryption as paid certificates, ensuring secure and encrypted communication.
Open and Transparent: As an open-source project, Let’s Encrypt’s processes and policies are transparent, contributing to internet security and trust.


For Synology NAS users, the integration of Let’s Encrypt within DSM makes setting up SSL/TLS a fluid and hassle-free experience, significantly lowering the barrier to implementing robust security measures. The alliance of Synology NAS devices’ powerful capabilities with Let’s Encrypt’s user-friendly certification authority creates a compelling and secure storage and management solution.

Before you go …

If you found the guide on setting up an SSL certificate for your Synology NAS helpful, you might be curious about which Synology NAS model is the best fit for your needs. I recommend checking out Which Synology NAS Should You Buy?. This article dives into the different models, comparing their features and performance, helping you make an informed decision for your setup. It’s a great next step to ensure you get the most out of your network storage solutions.

Full Disclosure

Any purchases made from clicks on links to products on this page may result in an affiliate commission for me. 

Please keep in mind that the quantity or price of items can change at any time.

As an Amazon  Associate, I earn from qualifying purchases.

As an Aliexpress Associate, I earn from qualifying purchases. 

Als Amazon-Partner verdiene ich an qualifizierten Verkäufen

Tech Expert & Blogger


Leave a Reply

Your email address will not be published. Required fields are marked *

For security, use of Google's reCAPTCHA service is required which is subject to the Google Privacy Policy and Terms of Use.