How Permit-All Mode Simplifies Troubleshooting Across Routing and Firewalls

Understanding the Challenge of Mixed Routing and Firewall Failures

When application traffic fails to reach its destination, teams must determine whether the problem lies in routing, firewall rules, NAT behavior, or a combination of all three. In many environments, these components overlap in ways that make traditional troubleshooting slow and error-prone. Engineers often have to run repeated tests, stage changes, or temporarily disable rules to understand why a flow is being blocked. The community example highlights a typical case: internet traffic intended for a public virtual IP is dropped at an edge firewall, leaving open questions about what happens after that enforcement point.

Digital twins fundamentally change this process by allowing teams to model traffic behavior end to end, including every routing hop and every security device. Instead of altering production configurations or relying on guesswork, teams can run non-intrusive analysis to separate the contributing factors. This provides early clarity on whether the path is functionally viable, whether additional enforcement points exist further along the flow, and whether routing misconfigurations could still break application access.

What Permit-All Mode Reveals in a Digital Twin

Permit-all mode allows engineers to ask a critical troubleshooting question: “What would happen to this traffic if every firewall and ACL permitted it?” Using the digital twin, this hypothetical analysis exposes the full routing behavior without risk to the live network. The tutorial demonstrates that by toggling this mode, the modeled traffic successfully reaches the top-of-rack switch, confirming that routing is functioning correctly. It also surfaces additional enforcement points deeper in the path where traffic would still be blocked.

This visibility helps teams distinguish between a firewall issue and a routing issue in seconds. It also highlights exactly which security devices must be evaluated or updated. The digital twin automatically identifies all relevant rules that apply to the flow, enabling targeted remediation instead of broad, disruptive policy adjustments. These insights are covered in the full community post, which provides screenshots and workflow details.

Gaining Clarity on Routing Behavior Before Making Changes

Before modifying any firewall rules, teams need to ensure that routing is not part of the problem. Permit-all mode provides that certainty by isolating routing from security behavior. Instead of staging tests or pushing trial configurations, engineers validate the full forwarding path inside the model. In the example case, this confirmed that every route, prefix, and hop was correctly aligned to deliver the traffic to its destination.

This eliminates unnecessary guesswork and prevents changes that could introduce new issues. With accurate modeling, teams avoid the common trap of adjusting firewall rules only to discover that routing loops, missing prefixes, or asymmetric paths were the real culprit. The community tutorial shows how this approach helps practitioners avoid multiple rounds of testing and rollback by conducting the analysis safely in the digital twin environment.

Reducing Troubleshooting Cycles and Improving Confidence

Permit-all mode shortens the troubleshooting cycle by revealing all enforcement points and all routing behavior in one analysis. According to the tutorial, without a digital twin this process may require repeated configuration changes, iterative tests, and coordination across teams. With permit-all, engineers know immediately whether the issue is isolated to one firewall or whether multiple devices need updates.

The result is faster incident resolution and higher confidence when making changes. Because all analysis happens off-network, teams avoid risk while validating end-to-end application reachability. The digital twin provides the clarity needed to prioritize work, reduce false assumptions, and accelerate root-cause diagnosis. For detailed steps and UI-level actions, readers can refer to the original community guide.