I did this Practice Exercise for CCNA Course ( Neil Anderson )

Stage 1

Initial Setup:

• All switches and routers were in factory default state.
• Verified VLAN database using show vlan brief – only default VLANs existed.

Configuration Steps:

1. Checked default switchport settings using:

   show interfaces switchport

2. Configured trunk links between switches:

   BASH

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   interface Gi0/1
   switchport mode trunk
   switchport trunk native vlan 199

   Click to expand and view more

3. Configured VTP:

   • On SW1:

     BASH

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     vtp mode server
     vtp domain FLACKBOX

     Click to expand and view more

   • On SW2:

     BASH

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     vtp mode transparent
     vtp domain FLACKBOX

     Click to expand and view more

   • On SW3:

     BASH

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     vtp mode client
     vtp domain FLACKBOX

     Click to expand and view more

4. Created VLANs on SW1 (VTP Server):

   BASH

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   vlan 10
   name ENG
   vlan 20
   name SALES
   vlan 199
   name NATIVE

   Click to expand and view more

5. VLAN propagation:

   • Verified VLANs automatically synced to SW3 (Client).
   • SW2 remained unchanged (Transparent mode).

6. Set trunk native VLAN on all trunk ports for security:

   BASH

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   switchport trunk native vlan 199

   Click to expand and view more

7. Configured access ports for PCs:

   • Example on SW3:

     BASH

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     int range f0/1 - 2
     switchport mode access
     switchport access vlan 10
     int f0/3
     switchport mode access
     switchport access vlan 20

     Click to expand and view more

8. Resolved native VLAN mismatch errors:

   • Matched native VLAN (199) on both sides of trunk links.
   • STP blocking issues resolved.

Verification:

• Verified VLANs using: show vlan brief
• Verified trunk status: show interfaces trunk
• Checked PC connectivity with ping commands (Eng1 - Eng3, Sales1 - Sales3)

Stage 2: Inter-VLAN Routing - Option 1

Using Separate Physical Interfaces on Router (R1)

Router (R1) Configuration

1. Enable and assign IP addresses to interfaces:

   • FastEthernet0/0 (for ENG VLAN):

     BASH

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     interface FastEthernet0/0
     ip address 10.10.10.1 255.255.255.0
     no shutdown

     Click to expand and view more

   • FastEthernet0/1 (for Sales VLAN):

     BASH

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     interface FastEthernet0/1
     ip address 10.10.20.1 255.255.255.0
     no shutdown

     Click to expand and view more

Both interfaces are UP and functioning

Switch (SW2) Configuration

1. VLAN Configuration:

   • VLAN 10 (ENG) and VLAN 20 (Sales) are already created:

     BASH

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     vlan 10
     name ENG
     
     vlan 20
     name Sales

     Click to expand and view more

2. Assign VLANs to Ports:

   • Fa0/1 → VLAN 10 (ENG):

     BASH

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     interface Fa0/1
     switchport mode access
     switchport access vlan 10

     Click to expand and view more

   • Fa0/2 → VLAN 20 (Sales):

     BASH

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     interface Fa0/2
     switchport mode access
     switchport access vlan 20

     Click to expand and view more

3. Trunk Port Configured:

   • Gig0/1 set as trunk with native VLAN 199:

     BASH

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     interface Gig0/1
     switchport trunk native vlan 199
     switchport mode trunk

     Click to expand and view more

VLAN interfaces Vlan10 and Vlan20 are up

Verification Steps

1. Connectivity from Eng1 (Fa0/1) to R1’s VLAN 20 (10.10.20.1)

   (pending)

2. Connectivity from Eng1 to Sales1 (across VLANs)

   

Stage 3: Inter-VLAN Routing - Option 2

Router-on-a-Stick Configuration

Router (R1) Configuration

1. Clear Existing IPs on Physical Interface
   • Removed IPs from FastEthernet0/0 to prepare for subinterfaces.
2. Configure Sub-Interfaces on FastEthernet0/0:

   • For VLAN 10 (ENG):

     BASH

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     interface FastEthernet0/0.10
     encapsulation dot1Q 10
     ip address 10.10.10.1 255.255.255.0

     Click to expand and view more

   • For VLAN 20 (Sales):

     BASH

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     interface FastEthernet0/0.20
     encapsulation dot1Q 20
     ip address 10.10.20.1 255.255.255.0

     Click to expand and view more

Both sub-interfaces are UP and functional

*FastEthernet0/0 now acts as trunk carrying tagged VLAN traffic*

Switch (SW2) Configuration

1. VLAN Setup:

   • VLANs already exist:

     BASH

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     vlan 10
     name ENG
     vlan 20
     name Sales
     vlan 199
     name NATIVE

     Click to expand and view more

2. Assign Access Ports:

   • Fa0/1 to VLAN 10 (ENG)

     BASH

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     interface Fa0/1
     switchport mode access
     switchport access vlan 10

     Click to expand and view more

   • Fa0/2 to VLAN 20 (Sales)

     BASH

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     interface Fa0/2
     switchport mode access
     switchport access vlan 20

     Click to expand and view more

3. Configure Trunk to Router:

   • Fa0/1 (connected to R1’s Fa0/0) as trunk:

     BASH

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     interface Fa0/1
     switchport trunk encapsulation dot1q
     switchport mode trunk
     switchport trunk allowed vlan 10,20

     Click to expand and view more

Trunk operational and forwarding VLAN 10 and 20 traffic

1. Set Default Gateway on SW2:

   BASH

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   ip default-gateway 10.10.10.1

   Click to expand and view more

Verification Steps

1. PC Eng1 (VLAN 10) should be able to:

   • Ping 10.10.20.1 (R1’s subinterface for VLAN 20)
   • Ping Sales1 PC

   

   Pinging Sales 3 from Eng 1

   

Pinging Eng1 from Sales 1

Conclusion

This lab successfully demonstrated three critical aspects of VLAN implementation:

• Basic VLAN Configuration: Established proper VLAN segmentation with VTP configuration across multiple switches
• Traditional Inter-VLAN Routing: Implemented routing using separate physical interfaces, proving the basic concept of inter-VLAN communication
• Router-on-a-Stick: Successfully configured and tested a more scalable inter-VLAN routing solution using subinterfaces

Key Learning Outcomes:

• Understanding of different VTP modes and their impact on VLAN propagation
• Practical experience with both physical and logical inter-VLAN routing methods
• Troubleshooting skills for native VLAN mismatches and connectivity issues

All configurations were verified with successful ping tests between VLANs, demonstrating a fully functional network design.