Vlan – Operational mode is down for one link

cisco-catalysttrunkvlan

I am setting up a simulated Cisco Packet Tracer with three Cisco Catalyst 2960 switches S1, S2 and S3. S1 being the trunk for S2 and S3.

I have three(3) interfaces F0/6, F0/11, F0/18 that are connected to my switches from three(3) PCs. I could ping from say PC1 to PC4 and and as well as PC3 to PC6 on same VLAN. However, PC2 to PC5 I could not ping and I found out that the interface F0/18 Operational Mode is down but the working one is not.

The first two F0/11 and F0/6 are connected to PC1, P3, PC4 and PC6 which are all working and have the following information using show interface <interface id> switchport command.

Name: Fa0/18
Switchport: Enabled
Administrative Mode: static access
Operational Mode: static access
Administrative Trunking Encapsulation: dot1q
Operational Trunking Encapsulation: native
Negotiation of Trunking: Off
Access Mode VLAN: 20 (Students)
Trunking Native Mode VLAN: 1 (Default)

But the first two again are working. However, F0/18 is not with the following information.

Name: Fa0/11
Switchport: Enabled
Administrative Mode: static access
Operational Mode: down
Administrative Trunking Encapsulation: dot1q
Operational Trunking Encapsulation: native
Negotiation of Trunking: Off
Access Mode VLAN: 10 (Faculty/Staff)
Trunking Native Mode VLAN: 1 (default)
.....<output omitted>
Appliance trust: none

The only difference I see is that the working ones has Appliance Trust: none but the non-working one has none.

Also this is an example running-configuration for S2:

Current configuration : 1248 bytes
!
version 12.2
no service timestamps log datetime msec
no service timestamps debug datetime msec
no service password-encryption
!
hostname S2
!
!
!
!
!
spanning-tree mode pvst
!
interface FastEthernet0/1
!
interface FastEthernet0/2
!
interface FastEthernet0/3
!
interface FastEthernet0/4
interface FastEthernet0/5
!
interface FastEthernet0/6
 switchport access vlan 30
 switchport mode access
!
interface FastEthernet0/7
!
interface FastEthernet0/8
!
interface FastEthernet0/9
!
interface FastEthernet0/10
!
interface FastEthernet0/11
 switchport access vlan 10
 switchport mode access
!
interface FastEthernet0/12
!
interface FastEthernet0/13
!
interface FastEthernet0/14
!
interface FastEthernet0/15
!
interface FastEthernet0/16
!
interface FastEthernet0/17
!
interface FastEthernet0/18
 switchport access vlan 20
 switchport mode access
!
interface FastEthernet0/19
!
interface FastEthernet0/20
!
interface FastEthernet0/21
!
interface FastEthernet0/22
!
interface FastEthernet0/23
!
interface FastEthernet0/24
!
interface GigabitEthernet0/1
!
interface GigabitEthernet0/2
 switchport trunk native vlan 99
 switchport mode trunk
!
interface Vlan1
no ip address
 shutdown
!
!
!
!
line con 0
!
line vty 0 4
login
line vty 5 15
login
!
!
end

What could have gone wrong?

I am just a newbie on this one, so please bear with me.

Best Answer

If you're working on this file -- 3.2.4.7 Packet Tracer - Troubleshooting a VLAN Implementation - Scenario 1.pka

PC5 is actually connected on Fa0/17 on S3 and not on Fa0/18(check by hovering to the green dot on S3).

-this is one of the flaws that I've seen on this activity file, other than wrong switch labels for ip addressing table, wrong port labels on logical diagram(i.e G1/1 instead of G0/1, etc.), and stuck to 60/70% completion even when everything is all good.

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