Installing and Configuring Tailscale on Synology NAS

Access Synology and Local Network Devices via Tailscale from Windows or Mobile (with Subnet Routes)

Objective

This guide walks you through:

1. Installing Tailscale on Synology DSM
2. Setting up your Synology as a Subnet Router
3. Allowing external devices (Windows / Mobile) to access Synology and the entire LAN using their original IPs

Even when your laptop or phone is on an external network (4G/5G/Wi-Fi elsewhere),
you’ll be able to access your Synology DSM and LAN devices using their native IPs, e.g.:

https://172.16.20.102:5001

Step 1. Download the .spk Package

1. Visit the official page:
   👉 https://pkgs.tailscale.com/stable/#spks
2. Go to Synology’s official page:
   👉 https://kb.synology.com/en-uk/DSM/tutorial/What_kind_of_CPU_does_my_NAS_have
   Find your NAS model in the list and note the CPU model (for example, “Intel Celeron J4125” or “Realtek RTD1296”).
   
3. Search the CPU model on Google, for example: Celeron J4125 architecture
   This tells you if it’s x86_64, aarch64 (ARM64), or armv5/7/8.
   
4. Download the appropriate file to your computer.

Step 2. Install via DSM GUI

1. Log in to DSM → open Package Center
2. Click Manual Install in the upper-right corner
3. Select the .spk file you just downloaded
4. Proceed through the wizard → Accept → Install
5. After installation, check Installed Packages → Tailscale

Step 3. Connect Synology to Tailscale

1. Open Tailscale from DSM Main Menu
2. Click “Log in to Tailscale”
3. Once authenticated, the DSM window will show: “Connected”

At the Tailscale window you’ll see something like:

100.65.23.25

This is your Synology’s Tailscale address — you’ll use it for testing later.

Step 4. Join the Same Tailnet from Windows

1. Install Tailscale for Windows
2. Sign in using the same account as on Synology

Step 5. Configure Subnet Routes

1. On your Windows computer where Tailscale is installed, open a browser and visit your Synology’s Tailscale IP address:5001.
   This lets you access DSM through the Tailscale network, even if you’re not on the same LAN.
2. DSM → Tailscale → Settings
3. If you see “Viewing” at the top right, click it → Sign in.
4. Check the option: Subnet router
5. Enter your LAN subnet (adjust to your actual network): 172.16.20.0/24

Step 6. Approve Subnet Routes in Tailscale Admin Console

1. On your Windows browser, open:
   👉 https://login.tailscale.com/admin/machines
2. Locate your Synology device (e.g., ds223j) → Edit route settings
3. You’ll see something like: Subnet routes: 172.16.20.0/24
4. Check it and Save

Step 7. Test Access from Windows or Mobile

• On your phone, install Tailscale from the App Store (iOS) or Google Play (Android).
• Open the app and sign in with the same account you used on Synology (e.g., Google or Microsoft).
• Once signed in, your Synology NAS should appear in the Devices list and show Connected.

• Now, you can directly open Synology’s original LAN IP (for example https://172.16.20.102:5001) from the phone — Tailscale will automatically route it through your NAS.
• You can also use Synology’s official mobile apps (such as DS File, DS Photo, DS Audio, etc.) and connect by entering the same LAN IP instead of QuickConnect or DDNS — they’ll work seamlessly through Tailscale.