When you set up a NAS at home or in the office and want to access it remotely, the question of static or dynamic IP ceases to be theoretical and becomes very practical: what type of IP do I need to make my NAS accessible, secure, and easy to manage? Many people get confused because they mix up public IPs, private IPs, VPN servers, DDNS, ports… and in the end, they don't know what settings to configure on the router or what service to contract with their internet provider.
In this article, we'll break down, step by step, how a NAS fits into this whole IP mess , what really changes between using dynamic or static IPs (both public and private), when it makes sense to pay for a static IP from your provider, when a dynamic IP + DDNS is sufficient, and what happens if you set up OpenVPN on the NAS itself or on your router. The goal is for you to end up with a clear understanding and know what's best for your specific situation, without any unnecessary hype.
Basic concepts: Public, private, static, dynamic, dedicated, and shared IP addresses
Before deciding anything for your NAS, it's important to clarify which IP address we're talking about, because the NAS's internal IP address is not the same as the public IP address you use to connect to the internet, and a dedicated IP address is not the same as a shared one.
Private IP vs. Public IP
Within your local area network (LAN), each device—PC, mobile phone, smart TV, and, of course, your NAS—has a private IP address . This IP is assigned by your router, usually via DHCP, and is only used for devices to communicate with each other within your home or office. If you need to find the IP addresses of devices on your network , there are helpful guides available. It is not visible from the internet.
The public IP address is something else entirely: it's the one your Internet Service Provider (ISP) assigns to your connection. This is the IP address your router uses to "go out" to the internet, and it's what websites, online services, and any external device see when accessing your network. This public IP address can be static or dynamic.
Dedicated IP vs. Shared IP
Furthermore, an IP address—usually the public one—can be dedicated or shared . If it's dedicated, only you (or your line) use it. If it's shared, other clients appear with the same public IP address, and the ISP uses NAT to separate the traffic from each one. This is common with some ISPs and also with many VPN services.
For a NAS that you want to access from outside, ideally the public IP should be dedicated (even if it's dynamic), because with some CG-NAT or shared IP configurations, port forwarding becomes complicated or impossible without alternative solutions like tunnels or external VPNs.
How IPs are assigned on your network: DHCP, static, and reservations
Most home networks use DHCP to assign dynamic private IPs . This means that when the NAS connects, the router gives it a free IP address within the internal range (for example, 192.168.1.37) for a certain period of time.
However, for services like NAS devices, network printers, IP cameras , or home servers, it's important that the internal IP address doesn't change every time the router restarts . For this, you have two options: assign a static IP address to the NAS itself or create a DHCP reservation on the router so that it always assigns the same private IP address to the NAS.
Typical private IP ranges
Private IPs are defined in the RFC 1918 standard and are taken from one of these reserved ranges, which are reused in networks around the world without conflict:
- 10.0.0.0-10.255.255.255, widely used in large or business networks
- 172.16.0.0-172.31.255.255, common in some organizations
- 192.168.0.0-192.168.255.255, the classic of home networks
Your NAS will have one of those addresses, something like 192.168.1.10 or 192.168.0.25 , and it's the one you'll use internally or as the destination for the router's port forwarding (for example, the famous UDP 1194 if you configure OpenVPN on the NAS).
What is a static IP (public and private) and what does it mean for your NAS?
A static IP address is one that doesn't change over time unless someone manually modifies it or the provider decides to reassign it in exceptional circumstances. This applies to both the NAS's internal IP address and your internet connection's public IP address.
Static private IP address on the NAS
On a local network, a static private IP address means you fix the NAS's address so that it's always the same, for example, 192.168.1.100. You can do this from the NAS itself or by reserving the IP address by MAC address on the router using static DHCP.
This is very practical because it facilitates port forwarding and internal access : if the router always knows that the NAS is at 192.168.1.100, you can create a permanent rule (for example, external port 5000 to internal 192.168.1.100:5000 to manage DSM, or UDP port 1194 to the NAS for OpenVPN).
Static public IP address assigned by the ISP
Static public IP addresses are the ones that usually cause the most confusion. In this case, your provider assigns you a fixed address that doesn't change when you restart your router or over time. This is commonly used by companies that host services accessible from the internet (websites, email, corporate VPNs, etc.).
For a home NAS, a static public IP offers some clear advantages:
- Highly predictable remote access: you always connect to the same IP, without depending on DDNS services.
- Ease of using "classic" DNSIf you want to point a domain or subdomain directly to your IP (like home.mydomain.com), a static IP simplifies the setup.
- Less fuss with whitelistsIf you want to limit access to your NAS or VPN by IP (for example, in a firewall or third-party services), having a stable IP helps a lot.
But it's not all advantages. Having a static public IP address with an exposed NAS has these disadvantages:
- More attack surfaceSince it doesn't change, it's a perfect target for brute-force attacks, continuous scans, or automated attempts against your open ports.
- Less privacyTracking your activity is easier, since everything comes from the same public IP address.
- Additional cost and limited availabilityMany ISPs only offer static IPs on business plans or with a monthly supplement.
- Rigidity after a breachIf your IP address is compromised (spam lists, continuous attacks, etc.), changing it is not always immediate.
What is a dynamic IP address and why are you almost certainly already using one?
A dynamic IP address is one that your provider automatically assigns from a pool of addresses and that can change periodically: when you restart the router, after a certain number of hours or days, or when the operator reorganizes resources.
In practice, for most fiber or ADSL users, the public IP address is dynamic by default . You might have the same IP address for weeks or months, but the ISP isn't committed to keeping it, and sooner or later it will change.
How are dynamic IPs (DHCP) managed?
The allocation of dynamic public IPs is also usually done via DHCP on the ISP's side . Your router requests an IP address, the ISP's DHCP server assigns it a free one from the available range, and when the "lease" expires, it can be renewed or changed.
In the case of private IPs on your LAN, it is the router that acts as a DHCP server and delivers dynamic IPs to devices , unless you force static IPs or reserve by MAC.
Advantages of dynamic IP for general use
For browsing, streaming, gaming, and typical home use, dynamic IP works wonderfully. Its advantages include:
- Included in almost all standard plansYou don't pay anything extra for it.
- Automatic management without manual configurationYou connect the router and that's it, the operator takes care of the rest.
- Slight privacy improvement: because it changes every so often, keeping track of your long-term activity becomes somewhat more complicated.
- Less "fixed goal"If you suffer scans or attacks on your IP, a change of IP can make the attackers lose track of you.
On the other hand, dynamic IPs make direct remote access to home services like NAS, game servers, or IP cameras a bit more complicated if you intend to log in simply by typing the public IP address into a client or browser.
NAS with dynamic or static IP on the local network: which is better
For the NAS, the critical IP address at the basic configuration level is the internal (private) IP address . If that IP address changes, port forwarding, firewall rules, and generally any service pointing to that address will be disabled.
Advantages of a static private IP address on a NAS
Having a static IP address on the NAS within the LAN is almost essential if you are going to:
- Configure port forwarding from the router to the NAS (HTTP/HTTPS, OpenVPN, FTP, etc.).
- Use it as a file or multimedia server for other devices that have it mapped by IP.
- Implement internal firewall rules IP-based to limit access on your own network.
In this context, the most convenient thing is usually to reserve the NAS's IP address via DHCP on the router (static assignment by MAC), thus avoiding address conflicts and continuing to manage everything from a single location.
Are there performance differences between static and dynamic internal IP?
No. There are no improvements in speed, ping, or stability simply because the IP address is static or dynamic, either on the LAN or to the internet. That's one of the most widespread myths. Latency and performance depend on line quality, packet routing, congestion, and hardware capacity, not on whether the IP address changes every few hours. If you want to optimize TCP/IP and reduce latency, there are practical guides on the most influential settings.
NAS with dynamic public IP: DDNS, tunnels and myths that no longer make sense
For years it was said that to access a NAS from outside, " you absolutely need a static public IP address ." Today, with DDNS services, integrated solutions from manufacturers themselves, and secure tunnels like Cloudflare Tunnel or similar, this is becoming less and less true.
Dynamic DNS (DDNS) for dynamic public IP
Dynamic DNS is a service that associates a constant domain name (for example, mydomain.ddns.net) with your public IP address, even if it changes. The NAS or router is responsible for updating the domain's IP address whenever it detects a change.
Virtually all modern NAS and router manufacturers offer built-in or recommended DDNS , and many even provide their own free domain. As a result, you can always access your NAS by typing a name (example.synology.me) regardless of whether your ISP has changed your public IP address that night. If you're interested in learning more about custom DNS and alternatives, there are resources that explain the advantages and risks.
Tunnels and solutions without opening ports
Another increasingly common approach is the use of secure tunnels that run from your network to an intermediary service (such as Cloudflare Tunnel, Tailscale, or proprietary solutions from some manufacturers). In this case, the router or NAS doesn't require a directly accessible public IP address or traditional port forwarding.
This debunks one of the biggest myths: that with a dynamic IP you can't expose anything to the outside world . These days, it's rare to find a NAS or home automation ecosystem that doesn't offer some secure remote access option without needing a static IP or manually opening ports.
OpenVPN on NAS: Do I need a static IP or is a dynamic IP sufficient?
If you've looked at tutorials for setting up OpenVPN on a Synology NAS or another manufacturer's NAS , you'll almost always have seen a step of "make sure your NAS IP is static" and "forward UDP port 1194 from the router to the NAS".
Why do they require a static IP address for the NAS?
In reality, what those tutorials want is for the NAS's private IP address not to change , because if the router redirects port 1194 to 192.168.1.50 and tomorrow the NAS changes to 192.168.1.32, the forwarding stops working and the VPN drops.
The correct solution is to configure the NAS with a static internal IP address (or DHCP reservation) . This doesn't necessarily mean contracting a static public IP address from your provider, just assigning the IP address within your LAN.
Why is UDP 1194 usually used and not TCP?
OpenVPN can work over UDP or TCP , but the most common default port is UDP 1194. UDP is preferred because:
- Reduce latency because there is no confirmation of each packet as in TCP.
- Avoid "TCP over TCP" (When you encapsulate TCP traffic within another TCP flow, inefficiencies and redundant retransmissions are generated).
- It tends to perform better for streaming, gaming, and interactive sessions through the VPN.
Even so, you can configure OpenVPN over TCP if your environment requires it (for example, to get through very restrictive firewalls), but the general recommendation for NAS is to use UDP unless you have a clear reason to do otherwise.
Is a static public IP better for OpenVPN?
It's not essential. It offers convenience because your VPN clients will always connect to the same IP address without relying on dynamic DNS, but with a dynamic public IP address and a properly configured DDNS, you'll achieve practically the same result.
In most home and small office scenarios, dynamic public IP + DDNS + NAS with fixed internal IP is more than enough to have a stable and functional OpenVPN.
Is it smarter to run OpenVPN on the router than on the NAS?
Another very common question is whether it's better to set up the OpenVPN server directly on the router instead of on the NAS.
Advantages of installing OpenVPN on the router
When you run OpenVPN on your router, it becomes the secure gateway to your entire network . Some clear advantages are:
- Full access to the LANBy connecting via VPN, you enter as if you were inside your home, seeing the NAS and the rest of the devices without any extra configuration.
- Less NAS exposureYou don't need to open specific NAS ports directly to the Internet, just the router's VPN port.
- Simpler architecture In many cases, this is because the router is designed to handle through traffic and NAT.
The main drawback is performance : many home routers have limited processors, and encrypting/decrypting high-speed VPN traffic can overload them. If your router is modest and your NAS is powerful, the NAS might handle the VPN load better.
Advantages of running OpenVPN on the NAS
If you run the VPN server on the NAS, the encryption and session management workload falls on a device that is typically more capable than the router. Furthermore:
- The NAS attendees themselves They usually make configuring OpenVPN and generating client profiles much easier.
- You have more granular control about which NAS services you expose to the VPN and which you don't.
- Some ISP routers are very limited and they don't allow you to set up a VPN on them, so a NAS is your only local option.
However, your NAS will still be accessible from the Internet through the VPN port (even if it is protected by credentials and certificates), so the security of the NAS itself becomes even more critical (updates, strong passwords, two-factor authentication, certificates, etc.).
VPN with static or dedicated IP: another way to have a "fixed" IP
If your internet provider doesn't offer a static public IP address or it's too expensive, you can use a VPN that includes a static or dedicated IP address . In this case, you connect to the VPN first, and all your internet traffic then goes through the VPN server's IP address.
Advantages of using a static IP address through a VPN
With a static or dedicated IP address from a VPN you get:
- Constant external IP address without having to change your plan with your ISP.
- More privacyBecause your real home IP address is not the one the internet sees, but the one from the VPN.
- Geographic flexibilityYou can choose a static IP address in another country or region to bypass geographical restrictions or access specific services.
Some providers offer shared static IPs (which you use with other customers) and others give the option of hiring a dedicated IP just for you, which makes it easier to whitelist IPs in external services but with less anonymity compared to other VPN users.
Common myths about static and dynamic IPs in NAS environments
Many myths circulate in forums and old guides that are no longer valid. Some of the most repeated are:
- "A static IP address provides faster speeds or better ping"False. Speed ​​and latency depend on line quality, route, and congestion, not on whether the IP address changes or not.
- "With a dynamic IP address, you can't access your NAS from outside."This is false in practice today. DDNS, integrated tunnels, and proprietary manufacturer services allow stable remote access with dynamic IPs.
- "A static IP address is more secure because it doesn't change."It's actually the opposite. A stationary target is easier to attack continuously.
- "Having a public IPv6 address makes everything insecure."With modern routers, the firewall already blocks unsolicited incoming traffic by default. The important thing is to configure the rules correctly, not to avoid IPv6 altogether.
How to tell if your IP is static or dynamic (public and private)
If you want to check what type of IP address you use, both within your network and to the Internet, you can do it in a few steps.
Check if your device's private IP address is static or dynamic
In all systems, the key is to see if the IP address is configured automatically (DHCP) or manually . In short:
- WindowsOpen the network settings of your active connection and look under "IP Assignment". If it says Automatic (DHCP), it's dynamic; if it says Manual, it's static.
- MacOSIn System Settings > Network > your connection > TCP/IP, check "Configure IPv4". "Using DHCP" is dynamic; "Manual" is static.
- AndroidIn the Wi-Fi settings, go to your network, look for "IP settings" and you will see DHCP (dynamic) or Static.
- iOSIn Settings > Wi-Fi > your network, under "Configure IP" you will see Automatic (dynamic) or Manual (static).
In the specific case of your NAS, you can see it in its network control panel: if the IP is automatically filled in by DHCP , it is dynamic; if you have entered the values ​​(IP, mask, gateway, DNS), it is static.
Check if your public IP address is static or dynamic
For a public IP address, the simplest trick is:
- Write your Current public IP address with a website that says "What is my IP address?".
- Restart the router (Turn it off or unplug it for a minute and then turn it back on).
- Check your public IP address again. If it has changed, You are using a dynamic IP address.If it remains the same, it may be static, although some ISPs maintain the same dynamic IP for long periods.
The only definitive confirmation will come from your operator: in many cases, static IP is listed as an additional service in the customer area or in the contract.
What type of IP address is best for your NAS and your internet usage?
The decision isn't so much a matter of "static IP is good, dynamic IP is bad" as it is "which combination makes the most sense for your situation ." For most home users, the best approach is usually:
- Static private IP address for the NAS within the LAN (either by setting it on the NAS itself or via DHCP reservation on the router).
- Dynamic public IP address of the ISPwhich is the one that comes standard and is cheaper, combined with DDNS or with the remote access solution from the NAS manufacturer.
- VPN server (OpenVPN or similar) on the router or NAS If you want secure remote access to your entire network and not just specific services.
It only makes sense to consider a static public IP contracted from the operator when you have very specific requirements: hosting business services with "traditional" DNS, applying strict IP policies in external firewalls, or ensuring that certain integrations always see the same address.
In online gaming environments, basic remote work, or intensive use of a home NAS, a well-configured combination of a static internal IP, a dynamic public IP, dynamic DNS, and proper VPN usage usually more than covers all needs without incurring extra costs or unnecessary complications. Share this information so other users can learn about it.