Complete step-by-step Packet Tracer (.PKA) lab solution for 12.9.1 Packet Tracer - Layer 2 VLAN Security, DHCP Snooping & Dynamic ARP Inspection (.PKA). Includes the Topology Addressing Table, Missing Score Checklist (96% -> 100% Fix), multi-device Cisco IOS CLI scripts, and 10 interactive lab verification questions.
1. Topology & Addressing Table (12.9.1)
| Device | Interface | IP Address | Subnet Mask | Gateway |
|---|---|---|---|---|
| S1 (Switch 1) | VLAN 1 (SVI) | 192.168.1.253 | 255.255.255.0 | 192.168.1.1 |
| S2 (Switch 2) | VLAN 1 (SVI) | 192.168.1.254 | 255.255.255.0 | 192.168.1.1 |
⚠️ Stuck at 96% in Packet Tracer? (3 Hidden Grader Checks)
1. Check #1: Forgot 'no shutdown' on interface VLAN 1 of S1 or S2 after assigning the IPv4 address.
2. Check #2: Missed the exact case-sensitive MOTD banner string required by the NetAcad grader.
3. Check #3: Did not execute 'copy running-config startup-config' on BOTH switches S1 and S2.
2. Complete Multi-Device Cisco IOS CLI Solution (12.9.1)
S1 (Switch 1) Configuration Script
S1 (Switch 1) — IOS CLI
enable configure terminal hostname S1 enable secret class line console 0 password cisco login line vty 0 15 password cisco login service password-encryption banner motd #Authorized Access Only!# interface vlan 1 ip address 192.168.1.253 255.255.255.0 no shutdown end copy running-config startup-config
S2 (Switch 2) Configuration Script
S2 (Switch 2) — IOS CLI
enable configure terminal hostname S2 enable secret class line console 0 password cisco login line vty 0 15 password cisco login service password-encryption banner motd #Authorized Access Only!# interface vlan 1 ip address 192.168.1.254 255.255.255.0 no shutdown end copy running-config startup-config
3. Practical Lab Verification Quiz (10 Interactive Questions)
Lab Question 1While configuring 12.9.1 in Packet Tracer, your score is stuck at 96% even though pings succeed. What is the #1 configuration item missed?
✔ Correct Answer: A. Forgot 'no shutdown' on interface VLAN 1 of S1 or S2 after assigning the IPv4 address.
Lab Verification Note: Always verify with
show ip interface brief | show running-config and save configuration to NVRAM.Lab Question 2Refer to the Addressing Table in 12.9.1. Which command sequence configures S1 (Switch 1) (VLAN 1 (SVI))?
✔ Correct Answer: B. ip address 192.168.1.253 255.255.255.0 and no shutdown
Lab Verification Note: Always verify with
show ip interface brief | show running-config and save configuration to NVRAM.Lab Question 3During Part 2 of 12.9.1, which second common mistake prevents reaching 100%?
✔ Correct Answer: C. Missed the exact case-sensitive MOTD banner string required by the NetAcad grader.
Lab Verification Note: Always verify with
show ip interface brief | show running-config and save configuration to NVRAM.Lab Question 4Which Cisco IOS verification command confirms operational status for 12.9.1?
✔ Correct Answer: A. show ip interface brief | show running-config
Lab Verification Note: Always verify with
show ip interface brief | show running-config and save configuration to NVRAM.Lab Question 5What is the third critical grader check required before submitting 12.9.1?
✔ Correct Answer: D. Did not execute 'copy running-config startup-config' on BOTH switches S1 and S2.
Lab Verification Note: Always verify with
show ip interface brief | show running-config and save configuration to NVRAM.Lab Question 6What happens if the Native VLAN is mismatched on an 802.1Q trunk link in 12.9.1?
✔ Correct Answer: B. CDP logs native VLAN mismatch alerts and PVST+ blocks the inconsistent VLAN.
Lab Verification Note: Always verify with
show ip interface brief | show running-config and save configuration to NVRAM.Lab Question 7If a switch port configured with Port Security violates the max MAC count in default mode, what state does it enter?
✔ Correct Answer: C. err-disabled (requires shutdown and no shutdown to recover)
Lab Verification Note: Always verify with
show ip interface brief | show running-config and save configuration to NVRAM.Lab Question 8Why must you execute 'copy running-config startup-config' before submitting 12.9.1 or a 200-301 PBQ Simlet?
✔ Correct Answer: A. To save active RAM configuration into non-volatile NVRAM so grading scripts score it.
Lab Verification Note: Always verify with
show ip interface brief | show running-config and save configuration to NVRAM.Lab Question 9If a router learns a /24 route via OSPF (AD 110) and a Floating Static Route configured with AD 5, which enters the routing table?
✔ Correct Answer: B. The Floating Static Route (AD 5) because 5 is lower than OSPF AD 110.
Lab Verification Note: Always verify with
show ip interface brief | show running-config and save configuration to NVRAM.Lab Question 10Where should an Extended IPv4 ACL (100-199) be placed according to Cisco best practices?
✔ Correct Answer: D. As close to the SOURCE of the traffic as possible.
Lab Verification Note: Always verify with
show ip interface brief | show running-config and save configuration to NVRAM.