This guide provides a concise, step-by-step overview for setting up a fully functional PACS system using Orthanc on a Synology NAS, with both local (LAN) and secure remote (VPN) access. It is designed as a practical reference for rapid deployment and troubleshooting, covering Docker installation, VPN configuration, and integration with DICOM viewers such as RadiAnt and Horos. The aim is to ensure a stable, reproducible, and secure workflow for storing, accessing, and retrieving imaging studies across devices and locations.

1. Install Orthanc PACS on Synology NAS (Docker)
a. Create container
- Open Container Manager → Create Container
- Use an Orthanc image (e.g.
jodogne/orthancor orthancteam/orthanc or equivalent)
b. Configure ports
4242→ DICOM8042→ Web interface
c. Configure volumes (IMPORTANT)
Map persistent storage (Synology folder → Container path) :
/volume1/docker/orthanc/config → /etc/orthanc
/volume1/docker/orthanc/db → /var/lib/orthanc/db
/volume1/docker/orthanc/import → /var/lib/orthanc/import (optional)
👉 Without this, data will be lost on container restart. – Enable Auto-restart
2. Configure Orthanc
Edit orthanc.json inside the config folder (edit username / password to use).
Basic required settings:
- AE Title:
ORTHANC - DICOM Port:
4242 - Enable remote access if needed
- Define DICOM peers (optional but recommended)
👉 See full template at the end.
3. Verify Orthanc is running
Open in browser:
http://<NAS-IP>:8042
Example:
http://192.168.1.13:8042
✔ If this does not open → container/network issue
4. Configure VPN (Remote Access)
a. Enable VPN Server on Synology
- Install VPN Server package
- Enable OpenVPN
b. Key settings
- Virtual IP range (e.g.
10.8.0.0) - ✔ Enable: “Allow clients to access server LAN”
👉 This is critical for accessing PACS remotely
c. Export configuration
- Export
.ovpnfile
d. Router configuration
- Port forward:
UDP 1194 → NAS local IP
e. Synology Firewall
Allow:
- UDP 1194 (VPN)
- TCP 4242 (DICOM)
- TCP 8042 (Web)
5. Configure PACS Viewer (RadiAnt / Horos)
a. Local Network (LAN)
Configure DICOM node:
- AE Title:
ORTHANC - IP Address:
192.168.1.13(NAS) - Port:
4242 - Retrieve Protocol:
C-GET(simpler setup)
Optional:
- Calling AE Title:
RADIANT(PC)HOROS(Mac)
b. Remote Access (via VPN)
Step 1 – Install OpenVPN client
- PC: OpenVPN GUI
- Mac: Tunnelblick / OpenVPN
Step 2 – Import config
- Load exported
.ovpn
Step 3 – Edit config file
Replace:
remote YOUR_IP 1194
With:
- Public IP OR
- DDNS (recommended), e.g.:
remote mynas.synology.me 1194
Step 4 – Connect to VPN
After connection:
Test:
ping 192.168.1.13
✔ If reachable → OK
Step 5 – Use SAME PACS settings as local
⚠️ Important:
Use internal NAS IP, NOT public IP
- IP:
192.168.1.13 - Port:
4242 - AE Title:
ORTHANC
6. (Optional but Recommended) DDNS Setup
Synology:
- Control Panel → External Access → DDNS
Example:
mynas.synology.me
👉 Avoids changing IP manually
7. DICOM Modalities (Optional but Recommended)
In orthanc.json, define known clients:
- RadiAnt (PC)
- Horos (Mac)
This improves:
- C-MOVE functionality
- Communication stability
8. Quick Troubleshooting Checklist
✔ Web UI opens (:8042)
✔ VPN connects successfully
✔ Can ping NAS (192.168.1.13)
✔ DICOM send works
✔ Query/Retrieve works
⚙️ Orthanc orthanc.json Template (Clean & Practical)
You can adapt this to your setup:
{
"Name": "Orthanc",
"StorageDirectory": "/var/lib/orthanc/db",
"DicomAet": "ORTHANC",
"DicomPort": 4242,
"RemoteAccessAllowed": true,
"AuthenticationEnabled": true,
"RegisteredUsers": {
"admin": "your_password"
},
"DicomModalities": {
"RADIANT": [ "RADIANT", "192.168.1.100", 104 ],
"HOROS": [ "HOROS", "192.168.1.101", 11112 ]
},
"HttpServerEnabled": true,
"HttpPort": 8042,
"OrthancExplorerEnabled": true,
"DefaultEncoding": "Latin1",
"DicomScpTimeout": 30,
"DicomScuTimeout": 10,
"MaximumStorageSize": 0,
"MaximumPatientCount": 0
}
🧠 Final Notes (from experience)
- C-GET works easier than C-MOVE (no routing issues)
- VPN is the safest way → avoid exposing DICOM port publicly
- Always test:
- Local first
- Then VPN
- Keep a backup of
orthanc.json
Get a printable PDF (1-page cheat sheet)
More details at NAS Storage for Horos
