Synology DSM Tip: Easily Change the DDNS Domain in Sharing Links for Enhanced Privacy

# Synology DSM Tip: Easily Change the DDNS Domain in Sharing Links for Enhanced Privacy ## The Core Problem: Protecting Your Public IP & Simplifying Video Production When using a Synology NAS, we typically set up DDNS (Dynamic DNS) to access it from the internet via a fixed domain name. However, when you create file sharing links in DSM, the system defaults to this primary DDNS domain, inadvertently exposing your public IP address. For content creators, this means having to blur the domain in every screen recording to protect privacy, adding to the post-production workload. --- ## The Solution: Add a Dedicated Domain for Sharing This video presents a simple and effective solution that doesn't require changing your existing DDNS setup. Instead, you can add an \"alias\" domain specifically for generating sharing links. ### Step-by-Step Guide: 1. Log in to your Synology DSM. 2. Go to **Control Panel** -> **External Access**. 3. Switch to the **Advanced** tab. 4. In the \"Hostname or static IP\" field, enter the new domain you want to use for sharing (e.g., `share.lib00.com`). 5. Click **Apply** (or Save). After completing these steps, when you create a new sharing link, DSM will automatically use this newly configured domain instead of your primary DDNS domain. --- ## Important Note: DNS Resolution Must Be Configured Separately It's crucial to understand that adding this domain in DSM **only changes the text of the generated link**. It does not automatically configure DNS resolution for this new domain. You must manually perform one of the following steps to make the link functional: - **For Public Access**: In your domain provider's DNS settings or your router's DDNS settings, point this new subdomain to your public IP address. - **For Local Testing/Demos**: As the video creator does, you can modify your local computer's `hosts` file to point the new domain to your NAS's internal IP address. This way, the domain only resolves within your local network, perfect for recording tutorials without ever exposing public information. --- ## Summary & Use Cases This handy tip not only solves the privacy concerns for content creators but also offers greater flexibility for all users. For instance, you could set strict firewall rules for your primary domain while having different access policies for the dedicated sharing domain, or simply use different domains for different services to keep your NAS management more organized and secure.