Is the order of Access List and Control List rules important?

• A. Yes
• B. No
• C. Sometimes
• D. Not specified

Answer: (A)

The order of Access Lists and Control Lists determines what actually happens to traffic because rules are evaluated in sequence and the first match wins. As a packet is processed, the device checks each rule from top to bottom and applies the action of the first rule that matches. That means where you place a specific deny or permit changes the outcome for many packets. For example, if you want to block a single host but allow others, you must place that block rule before any broader permit rule; otherwise the broad permit might match first and the block would never take effect. There’s usually an implicit deny at the end for anything that doesn’t match any rule, which reinforces why you must be explicit about what should be allowed. This is why the order is important for implementing the intended traffic policy.