Question 640
A security ACL has sequence 10 permit ip any any followed by sequence 20 deny tcp any host 198.51.100.8 eq 23. The Telnet deny never matches. What is the root problem?
Explanation
Correct Answer
IOS ACL processing stops at the first matching ACE. A permit for all IPv4 traffic above the Telnet deny makes the deny unreachable for those packets.
Incorrect Answers
Host matching is valid in a destination field; rule order is the problem.
Telnet uses TCP destination port 23 as written, but the earlier permit shadows the deny.
An ACL is a packet filter; adding a static route is not a repair for shadowed ACE order.