22 Firewall Best Practices for Stronger Network Security

Firewalls are meant to be a line of defense – but without regular attention, they can leave your business network more exposed than protected.

Following firewall best practices can help you reduce that risk. It gives you a clearer picture of what’s allowed on your network, improves response time when issues come up, and makes it easier to stay ahead of compliance requirements.

In this blog, we’ll break down essential firewall best practices for building stronger, more manageable protection across your environment.

Why Do Firewall Security Best Practices Matter?

Firewalls can be powerful tools when they’re configured and monitored correctly. However, when they’re mismanaged or neglected, they can become a liability. Many data breaches happen because firewall settings weren’t reviewed or policies weren’t clear. 

Taking time to review your firewall strategy can improve visibility and reduce blind spots in your security setup. If you’re not sure where to begin, Aseva’s cybersecurity experts can help you evaluate what’s working, what’s not, and how to make improvements without disrupting your daily operations.

Firewall Configuration Best Practices

Following firewall configuration best practices can help your IT teams align security tools with your business needs. Here are some tips for strengthening your setup:

1. Start With a New Rule Set

Avoid reusing outdated rule sets. Start with what you know your users and systems will actually need, then build from there.

2. Apply the Principle of Least Privilege

The principle of least privilege enables your firewall to limit access where possible rather than allowing broad permissions by default. 

3. Use Network Segmentation

Divide your network traffic between different user groups, devices, and applications to contain threats and isolate your critical systems.

4. Enable Logging 

Logs can help you understand how traffic is flowing across the network. They can also be useful when troubleshooting or investigating security issues.

5. Update Configurations

Firewall rules should reflect how your network operates now, not how it worked last year. Schedule time to review and update configurations annually.

6. Test Before Pushing Live

If your firewall supports a test environment or staging option, you should use it. Testing rule changes before they go live helps reduce the chance of unintended disruptions.

Firewall Security Best Practices

Securing firewalls is an ongoing process. Some best practices for keeping your firewalls secure include:

1. Keep Firmware Updated

Outdated firmware leaves firewalls exposed to known vulnerabilities. Deploy new patches right away or work with a partner like Aseva to make sure your security tools stay up to date.

2. Automate Alerts 

Automated alerts let your IT teams know when something unusual or potentially dangerous is happening, so they can respond early and limit the impact on your systems.

3. Schedule Audits

Audits, whether internal or through a trusted security partner, can reveal oversights that your teams might miss during day-to-day firewall management.

4. Back Up Configurations

Having a recent backup of all data across your network can make it easier to recover from a failed update or system outage.

5. Limit Administrative Access

Only give firewall access to the people who truly need it. Use role-based access controls and enable MFA to add an extra layer of protection.

Firewall Policy Best Practices

Firewall rules are only as effective as the policies supporting them. These firewall policy best practices can help you ensure clarity and accountability:

1. Document Policies

Each firewall rule should have a stated purpose and a person responsible for it, all laid out in clear, easy-to-access documentation.

2. Standardize Across Locations

Apply firewall policies across each of your locations consistently to prevent gaps in protection across different offices or environments.

3. Clean Rules Regularly

Rules that no longer apply to your operations can weaken security and complicate troubleshooting. Remove them as part of regular maintenance.

4. Set App-Aware Policies

Next-gen firewalls often support controls based on application types, so your teams get more context and flexibility than relying on port numbers alone.

5. Limit Exceptions

Rule exceptions can introduce risk to your network, so they deserve extra attention. Make sure they’re always documented and temporary whenever possible.

Firewall Placement Best Practices

A firewall’s effectiveness largely depends on where and how you deploy it. Here are some tips to ensure your firewall is in the right place:

1. Protect the Perimeter

Position firewalls at the edge of the network to filter traffic entering and leaving. Filtering at these points can make it easier to spot unwanted or malicious connections.

2. Use Internal Segmentation

Segment your network by placing firewalls between departments or functions. This helps stop threats from moving laterally through your network, even if they’ve breached the perimeter.

3. Secure Cloud Workloads

Cloud infrastructure needs firewall protection, just like on-prem environments. Use virtual firewalls or cloud-native tools to control traffic across your cloud services.

4. Support Branch Offices

If your organization spans across multiple sites, place a firewall in each location – or deploy a cloud firewall to provide consistent protection across your entire network.

5. Don’t Overcomplicate

Firewall placement should be thoughtful, not excessive. Aseva’s consultants can help you find the right balance between security and simplicity.

6. Design for Redundancy

Operations can come to a halt if a firewall fails and there’s no backup. Implement high-availability configurations to avoid downtime and support business continuity.

What Are Common Pitfalls in Firewall Security?

Even with the best intentions, businesses can stumble in their firewall strategies. Some common pitfalls include:

• Allowing overly permissive rules that grant broad access.
• Ignoring shadow IT applications that bypass corporate policies.
• Failing to update rules after staff or projects change.
• Underestimating cloud security needs leaving workloads vulnerable.
• Lack of visibility due to inconsistent logging and reporting.

Working with a trusted partner can help you avoid these missteps. Aseva’s cybersecurity experts regularly help IT teams solve security problems by delivering integrated solutions tailored to your organization’s needs – so you get the right tools and support.

Bring Firewall Best Practices Together With Aseva

Firewalls are a living part of your network. Taking time to review configuration, fine-tune placement, and clarify your policies makes your firewall more effective and easier to manage. It’s worth the effort, especially when it helps prevent incidents down the road.

Whether you’re looking to refresh your setup or just need help understanding where to start, Aseva’s expert technology consultants are here to support you. We’ll work with your team to design a cybersecurity strategy that fits your goals, your resources, and your environment.

Ready to strengthen your firewall strategy? Get started with Aseva today.