When you need to protect a network, Access Control Lists (ACLs) are some of your first lines of defense. ACLs act like digital bouncers that determine who gets in and who’s denied access. Commonly used in firewalls and routers, they allow or restrict traffic based on factors like the source or destination IP addresses, as well as protocols and ports.
A Domain Name System (DNS) ACL defines these permissions based on domain name resolution and IP behavior. For example, a DNS ACL may restrict access to a resource unless it comes from a trusted domain or IP.
Proper implementation of Dynamic DNS firewall rules can protect your data by enforcing access policies to stop unauthorized entry, all while allowing employees to get to the infrastructure they need to access.
Challenges With Traditional ACL Management
There are three key reasons why managing your ACL rules the old-fashioned way can be a headache, and they are as follows:
They Count on Static IPs
Your ACLs can become outdated as soon as your ISP assigns a different address to your device, effectively throwing all your hard work down the drain.
This also becomes an issue when employees travel and need to access company networks. As they transition between networks, the IP address will change, preventing them from accessing the company infrastructure.
You Must Manually Update Your Lists All the Time
When IPs change, like when employees move locations, you need to update your ACLs. And you must do so by hand, every time. That can take long enough with one device or location, but it’s far more likely that you’ll need to update your records for several different entries.
There Are Greater Security Risks
If your ACLs are wrong, authorized users can get locked out, and unauthorized individuals may slip by your firewall. No matter how you slice it, it’s bad news.
How DDNS Solves ACL Challenges
Setting up Dynamic DNS (DDNS) can be a real game changer! DDNS simplifies your life by mapping a hostname to a dynamic IP address. That means you’ll no longer have to risk tying ACL rules to an IP address that might change. Even if your IP address changes, the hostname will keep pointing to that device.
DDNS-based firewall rules automate the updating process, which means your ACLs will easily reference correct and up-to-date information. Further benefits of using dynamic DNS firewall rules include:
- Eliminating the need to manually track IP changes
- Keeping your DNS ACL synced with real-time IP data
- Ensuring that only authorized devices gain access
- Spending less time configuring your DNS-based firewall rules
Step-by-Step Guide: Implementing DDNS for ACLs
Now that you’re ready to streamline your DNS firewall rules, here’s how to use a DDNS to power smarter ACL configurations:
Choosing a Reliable DDNS Provider
Your first step involves choosing a provider with a global footprint and robust uptime. Make sure the one you select offers easy integration with routers and firewalls.
No-IP offers a truly global presence and fast DNS resolution. Our reliable, enterprise-grade services make us a great fit for everyone from individuals to large businesses. No-IP is compatible with most consumer and enterprise routers and firewalls, as well as consumer devices, ensuring compatibility across the board.
Setting Up a DDNS Hostname
Next, you’ll need to set up a dynamic DNS hostname. Here’s how the process works with No-IP:
- Create a free No-IP account
- Navigate to your dashboard and click “Add Hostname”
- Choose a subdomain (like myhomeoffice.ddns.net)
- Enter your IP address or hostname target
- Select the appropriate record type (usually A Record)
- Save your settings
Your hostname is now linked to your device’s public IP. It’s truly as simple as that, and it means you can spend more time building a secure infrastructure to protect your devices and data.
Configuring ACLs With Your DDNS Hostname
Instead of hardcoding an IP address into your firewall or router ACL, use the hostname you created earlier. Many modern firewalls support hostname-based ACL entries natively, so even if the IP address changes, your DNS ACL will stay up to date. You can repeat the steps above for each hostname and ACL you need to configure.
Testing and Monitoring ACL Functionality
You want to make sure that traffic is going where you need it to, so use firewall logs or pings to ensure that your hostname resolves correctly. Test connectivity from approved and non-approved locations to see if the firewall is filtering traffic as designed. If you’re curious to know more about testing and monitoring your DNS ACL, check out our guide, which includes a host of tips for checking if your firewall ports are open correctly.
Take Control of Your Network Security
No-IP offers premium, industry-leading DDNS and managed DNS services that are perfect for firewall and ACL automation. Our team has decades of experience and can identify the ideal solution for your needs. What’s more, we provide a user-friendly dashboard that will make creating and managing your DNS ACL effortless.
Sign up for a free No-IP account to get started, and know that our support team is standing by to provide expert guidance on implementing DDNS for ACLs.