What does ACL Conflict Validator | Firewall Rule Analyzer do?

Analyze access-list rules, conflicts, overlaps, and permit-deny behavior for firewall and router policy planning.

Network engineers, sysadmins, DevOps teams, security learners, and technical operators can use this browser-based workflow.

Firewall Rule Conflict Lab

Identify redundant, shadowed, or conflicting Access Control Rules to optimize firewall performance and security posture.

Action

Protocol

Source IP

Dest IP

Understanding Rule Conflicts

Firewalls and routers process Access Lists (ACLs) from top to bottom. The first matching rule wins. This sequential order creates two common types of logic errors:

Shadowed Rules: A rule that can NEVER be hit because a previous rule covers the exact same conditions. For example, if rule #1 denies everything from `10.0.0.0/8`, a rule #2 permitting `10.0.0.1` is "shadowed" and will never execute.
Redundant Rules: A rule that adds no value. For example, if rule #1 permits `any any`, then a second rule permitting `10.1.1.1` is redundant because the traffic was already permitted.