Lab 06 — Ethernet Switching Fundamentals

Mission Information

Item	Details
Lab	06
Lab Name	Ethernet Switching Fundamentals
Track	CompTIA Network+
Difficulty	Beginner–Intermediate
Estimated Time	100–130 minutes
Primary Role	Network Technician / Junior Network Administrator
Environment	Network+ Virtual Switching Lab
Primary Systems	NETPLUS-ADMIN, NETPLUS-CLIENT01, NETPLUS-SERVER01, NETPLUS-SW01
Primary Tools	Virtual Switch / Managed Switch CLI, Wireshark, ping, ARP tools
Skills	Ethernet Switching, MAC Learning, Forwarding, Flooding, Broadcast Domains, Collision Domains, Interface Troubleshooting

Mission Objective: Understand how Ethernet switches learn MAC addresses, make forwarding decisions, handle broadcasts and unknown unicasts, and how interface state, speed, duplex, and topology influence Layer 2 communication.

Mission Scenario

You are working as a Junior Network Technician at GHC Enterprise.

Your network has expanded from direct virtual connectivity into a switched Ethernet environment.

The topology is now:

NETPLUS-ADMIN
10.10.10.10
      |
      |
   Port 1
      |
+----------------+
|  NETPLUS-SW01  |
+----------------+
   |          |
Port 2      Port 3
   |          |
   |          |
CLIENT01    SERVER01
10.10.10.20 10.10.10.30

The senior administrator asks you:

“How does the switch know where to send an Ethernet frame?”

Your task is to investigate how the switch:

Receives Frame
      ↓
Learns Source MAC
      ↓
Looks Up Destination MAC
      ↓
Forwards / Floods / Filters
      ↓
Updates MAC Address Table

You will also troubleshoot common switching issues.

Mission Objectives

By completing this lab, you will be able to:

explain Ethernet switching
understand switch ports
understand MAC address tables
observe dynamic MAC learning
identify source MAC learning behavior
explain destination MAC lookup
distinguish forwarding from flooding
understand unknown unicast flooding
understand broadcast forwarding
understand frame filtering
identify collision domains
identify broadcast domains
understand full duplex and half duplex
understand speed negotiation concepts
inspect interface state
troubleshoot disabled interfaces
recognize incorrect speed/duplex symptoms
understand MAC table aging
clear dynamic MAC entries safely
verify switched connectivity
document a switched topology

1. Build the Switching Topology

Add a Layer 2 switch:

NETPLUS-SW01

Connect:

NETPLUS-ADMIN
      ↓
Switch Port 1

NETPLUS-CLIENT01
      ↓
Switch Port 2

NETPLUS-SERVER01
      ↓
Switch Port 3

Logical topology:

           NETPLUS-SW01
        +----------------+
        |                |
        |                |
   Port 1    Port 2    Port 3
      |         |         |
      |         |         |
   ADMIN     CLIENT01   SERVER01
  .10          .20        .30

2. Verify IPv4 Addressing

Confirm:

NETPLUS-ADMIN
10.10.10.10/24

NETPLUS-CLIENT01
10.10.10.20/24

NETPLUS-SERVER01
10.10.10.30/24

All three systems should remain in:

10.10.10.0/24

3. Verify Endpoint Interfaces

On Linux:

ip link

On Windows:

Get-NetAdapter

Confirm the interfaces connected to the switch are:

UP

4. Verify Baseline Connectivity

From ADMIN:

ping -c 3 10.10.10.20

Then:

ping -c 3 10.10.10.30

From CLIENT01:

ping 10.10.10.30

All should succeed.

5. Understand What a Switch Does

A Layer 2 switch receives:

Ethernet Frames

and makes forwarding decisions primarily using:

Destination MAC Address

Conceptually:

Frame Arrives
      ↓
Learn Source MAC
      ↓
Read Destination MAC
      ↓
Check MAC Address Table
      ↓
Forward / Flood / Filter

6. Understand the MAC Address Table

A switch builds a table resembling:

MAC Address	Port
ADMIN MAC	Port 1
CLIENT01 MAC	Port 2
SERVER01 MAC	Port 3

This may also be called:

MAC Table

or:

CAM Table

depending on platform terminology.

7. How MAC Learning Works

When a frame arrives:

Source MAC:
AA:AA:AA:AA:AA:AA

Incoming Port:
Port 1

the switch learns:

AA:AA:AA:AA:AA:AA
      ↓
Port 1

Important:

Switches learn from the source MAC address, not from the destination MAC address.

8. Record Endpoint MAC Addresses

On ADMIN:

ip link

On CLIENT01:

getmac

On SERVER01:

ip link

Create:

Host	MAC	Connected Port
ADMIN	`<MAC>`	Port 1
CLIENT01	`<MAC>`	Port 2
SERVER01	`<MAC>`	Port 3

9. Inspect the Switch MAC Table

If your switch supports a Cisco-like CLI:

show mac address-table

or equivalent.

Initially, the table may be empty or partially populated.

Record what you see.

10. Clear Dynamic MAC Entries

Inside the lab, if supported:

clear mac address-table dynamic

or the equivalent command for your platform.

Do not clear production switch tables.

11. Generate Traffic from ADMIN

From NETPLUS-ADMIN:

ping -c 2 10.10.10.20

Then inspect the MAC table again.

You should see ADMIN and CLIENT01 learned.

12. Observe Source MAC Learning

The sequence is approximately:

ADMIN sends frame
      ↓
Frame enters Port 1
      ↓
Switch reads source MAC
      ↓
Learns:
ADMIN MAC → Port 1

When CLIENT01 replies:

CLIENT01 frame enters Port 2
      ↓
Switch learns:
CLIENT01 MAC → Port 2

13. Generate Traffic to SERVER01

Run:

ping -c 2 10.10.10.30

Inspect:

show mac address-table

You should now see:

ADMIN MAC → Port 1

CLIENT01 MAC → Port 2

SERVER01 MAC → Port 3

14. Understand Known Unicast Forwarding

Suppose ADMIN sends:

Destination MAC:
SERVER01 MAC

The switch checks its table:

SERVER01 MAC
      ↓
Port 3

Therefore:

Frame received on Port 1
      ↓
Forward only to Port 3

This is:

Known Unicast Forwarding

15. Understand Frame Filtering

Suppose two devices somehow communicate through the same switch port downstream.

If the source and destination are both known on the same outgoing port, the switch may not need to forward the frame to other ports.

This behavior is conceptually:

Filtering

A switch avoids sending frames where they are not required.

16. Understand Unknown Unicast

Suppose the switch receives:

Destination MAC:
DD:DD:DD:DD:DD:DD

but has no table entry.

The switch does not know which port owns the MAC.

Therefore it may:

Flood the frame

out other ports in the same VLAN.

17. Unknown Unicast Flooding

Conceptually:

Frame enters Port 1
      ↓
Destination unknown
      ↓
Flood:
Port 2
Port 3
Port 4
...

except the port where the frame arrived.

18. Why Unknown Unicast Flooding Exists

The switch needs to ensure that the destination still has a chance to receive the frame.

Once the destination replies:

Reply arrives
      ↓
Source MAC learned
      ↓
Future traffic forwarded directly

19. Observe Unknown Destination Behavior

Clear the switch MAC table.

Then immediately initiate traffic between endpoints.

If your simulator or physical lab allows traffic observation across ports, monitor the initial forwarding behavior.

You should conceptually observe:

Initial Traffic
=
Flooding possible

Later Traffic
=
Known unicast forwarding

20. Understand Broadcast Forwarding

Ethernet broadcast destination:

ff:ff:ff:ff:ff:ff

When a switch receives a broadcast:

Broadcast enters Port 1
      ↓
Switch forwards to all other ports
within the same VLAN

21. Generate an ARP Broadcast

Clear ADMIN’s ARP entry for SERVER01.

Linux:

sudo ip neigh del 10.10.10.30 dev <interface>

Start Wireshark.

Apply:

arp

Then:

ping -c 1 10.10.10.30

Observe the ARP broadcast.

22. Relate ARP to Switching

ARP request:

Ethernet Destination:
ff:ff:ff:ff:ff:ff

The switch floods it across the VLAN.

SERVER01 responds:

ARP Reply

The switch learns SERVER01’s MAC from the response source.

23. Understand Switch Learning During ARP

The exchange creates two useful effects:

ADMIN sends ARP request
      ↓
Switch learns ADMIN MAC

then:

SERVER01 sends ARP reply
      ↓
Switch learns SERVER01 MAC

Therefore ARP and switch learning often occur together.

24. Inspect Ethernet Traffic in Wireshark

Capture an ICMP packet after ARP resolution.

Expand:

Ethernet II

Record:

Source MAC:

Destination MAC:

Compare with the switch MAC table.

25. Validate Forwarding Logic

For ADMIN → SERVER01:

Source MAC:
ADMIN MAC

Destination MAC:
SERVER01 MAC

Switch table:

ADMIN MAC → Port 1
SERVER01 MAC → Port 3

Therefore the expected decision is:

Port 1
  ↓
Port 3

26. Understand Broadcast Domains

All devices in the same VLAN belong to the same:

Broadcast Domain

Current topology:

ADMIN
CLIENT01
SERVER01

is one broadcast domain if all are in the same VLAN.

27. Understand Collision Domains

With modern switched Ethernet, each switch port represents a separate collision domain.

Topology:

Port 1
=
Collision Domain 1

Port 2
=
Collision Domain 2

Port 3
=
Collision Domain 3

This is very different from old shared Ethernet hubs.

28. Switch vs Hub

Hub

Conceptually:

Frame In
   ↓
Repeat Out Every Port

Switch

Frame In
   ↓
Learn Source
   ↓
Check Destination
   ↓
Forward Intelligently

29. Collision Domain Comparison

With a hub:

Multiple Devices
      ↓
Shared Collision Domain

With a switch:

Device
  ↓
Dedicated Switch Port
  ↓
Separate Collision Domain

30. Broadcast Domain Comparison

A normal Layer 2 switch without VLAN separation does not automatically create a new broadcast domain per port.

Instead:

All Ports in VLAN 1
      ↓
One Broadcast Domain

VLANs will change this in Lab 07.

31. Understand Full Duplex

Full-duplex communication allows:

Transmit
+
Receive

simultaneously.

Modern switched Ethernet commonly operates:

Full Duplex

32. Understand Half Duplex

Half-duplex allows communication in both directions, but not simultaneously.

Conceptually:

Send
or
Receive

Classic shared Ethernet environments may use half duplex.

33. Compare Duplex Modes

Mode	Send and Receive Simultaneously?
Half Duplex	No
Full Duplex	Yes

34. Understand Auto-Negotiation

Ethernet interfaces may automatically negotiate:

Speed

Duplex

Possible speeds include:

100 Mbps

1 Gbps

2.5 Gbps

10 Gbps

depending on interface capabilities.

35. Inspect Linux Interface State

Run:

ip link

If available:

sudo ethtool <interface>

Review:

Speed:

Duplex:

Link detected:

36. Inspect Windows Link Speed

Run:

Get-NetAdapter

Review:

Name

Status

LinkSpeed

37. Inspect Switch Interface Status

On a managed switch, use a platform-appropriate command.

Cisco-like examples:

show interfaces status

and:

show interfaces

Record:

Port

Status

Speed

Duplex

VLAN

38. Build the Interface Table

Port	Connected Host	Status	Speed	Duplex
1	ADMIN	Up	`<speed>`	Full
2	CLIENT01	Up	`<speed>`	Full
3	SERVER01	Up	`<speed>`	Full

39. Understand Administratively Down

A switch interface may be physically connected but manually disabled.

Typical state:

Administratively Down

Meaning:

Configuration
      ↓
Port Disabled

40. Troubleshooting Scenario — Disabled Switch Port

Disable the SERVER01 switch port using your lab switch/simulator.

For Cisco-like syntax:

interface <port>
shutdown

Then test:

ping 10.10.10.30

Expected:

Failure

41. Investigate the Failure

Check:

Switch Port Status

Then endpoint:

ip link

or Windows equivalent.

You should determine whether:

Endpoint Interface
or
Switch Port

is causing the problem.

42. Re-enable the Port

Cisco-like example:

interface <port>
no shutdown

Verify:

Port Up

Then:

ping -c 2 10.10.10.30

Expected:

Success

43. Understand Port LEDs Conceptually

On physical switches, LEDs may indicate:

Link

Activity

Speed

Errors

They provide useful Layer 1/Layer 2 troubleshooting clues.

44. Troubleshooting Scenario — Cable / Virtual Link Disconnected

Disconnect CLIENT01 from the virtual switch.

Observe:

Switch Port:
Down

and:

Client:
No Layer 2 Connectivity

Reconnect after testing.

45. Understand MAC Aging

Dynamic MAC entries do not normally remain forever.

After a period of inactivity:

Dynamic MAC Entry
      ↓
Aging Timer
      ↓
Removed

When traffic resumes:

Switch Learns MAC Again

46. Why MAC Aging Exists

Devices can:

Move Ports

Disconnect

Reconnect

Change Network Location

Without aging, the table could contain outdated information indefinitely.

47. Observe MAC Aging if Practical

Inspect:

show mac address-table

Stop traffic from one endpoint.

Wait for the platform’s configured aging period if reasonable.

Observe whether the entry disappears.

If the default timer is too long for the lab, review the configured aging timer instead of waiting.

48. Understand Dynamic vs Static MAC Entries

Dynamic

Learned Automatically

Static

Configured Manually

Dynamic entries are the normal behavior for ordinary endpoint learning.

49. Troubleshooting Scenario — Host Moves Ports

Move NETPLUS-CLIENT01 from:

Port 2

to:

Port 4

Generate traffic.

Inspect the MAC table.

Expected:

CLIENT01 MAC
      ↓
Port 4

The switch should relearn the new location.

50. Understand MAC Moves

A MAC address appearing on a new port can mean:

Device physically moved

VM moved

Network topology changed

Redundant topology event

Possible Layer 2 issue

Context is required.

51. Troubleshooting Scenario — Duplicate MAC Concept

Duplicate MAC addresses are less common than duplicate IP addresses but can create major forwarding confusion.

Conceptually:

MAC-A
 ↓
Port 2

then suddenly:

MAC-A
 ↓
Port 3

The switch may repeatedly update the entry.

This is sometimes referred to as:

MAC Flapping

52. Understand MAC Flapping

Conceptually:

MAC X learned on Port 1
       ↓
MAC X learned on Port 2
       ↓
MAC X learned on Port 1
       ↓
MAC X learned on Port 2

Possible causes include:

Layer 2 Loop

Misconfiguration

Duplicate MAC

Virtualization Behavior

53. Do Not Simulate Harmful Looping Yet

Do not intentionally create an uncontrolled physical Layer 2 loop in this lab.

Loop behavior and prevention will be investigated safely in:

Lab 08 — Spanning Tree and Layer 2 Redundancy

54. Understand Unknown Unicast vs Broadcast

These are different.

Broadcast

Destination MAC:

ff:ff:ff:ff:ff:ff

Purposefully addressed to all devices in the broadcast domain.

Unknown Unicast

Destination is a specific unicast MAC:

AA:BB:CC:DD:EE:FF

but the switch does not know the port.

The switch may flood it temporarily.

55. Understand Flooding vs Forwarding

Forwarding

Destination MAC Known
      ↓
Send to One Correct Port

Flooding

Destination Unknown or Broadcast
      ↓
Send to Multiple Ports
within VLAN

56. Understand Filtering

A switch can avoid unnecessary forwarding.

Conceptually:

Frame does not need Port X
      ↓
Do not transmit on Port X

This is one reason switches are more efficient than hubs.

57. Build the Switch Decision Process

Use:

Frame Arrives
      ↓
Learn Source MAC
      ↓
Destination Broadcast?
      ↓
Yes → Flood
      ↓
No
      ↓
Destination MAC Known?
      ↓
No → Unknown Unicast Flood
      ↓
Yes
      ↓
Destination on Same Incoming Port?
      ↓
Yes → Filter
      ↓
No → Forward to Known Port

58. Inspect Packet Capture During Switching

Wireshark on one endpoint normally only shows frames visible to that endpoint’s virtual/physical interface.

You may not see all switch-port forwarding behavior unless:

Port Mirroring

SPAN

Virtual-Switch Capture

Simulator Packet Mode

is enabled.

This is expected.

59. Understand Port Mirroring

Port mirroring copies traffic from selected switch ports or VLANs to an analysis port.

Conceptually:

Production Port
      ↓
Switch
      ↓
Mirror Copy
      ↓
Analyzer / Wireshark

This supports monitoring and troubleshooting.

60. Configure Port Mirroring Conceptually

Depending on your platform, configure a mirror/SPAN session to copy selected lab traffic to the analyst interface.

Do not mirror unnecessary traffic in production environments without authorization and capacity planning.

61. Analyze Mirrored Traffic

If supported, capture traffic between:

CLIENT01
      ↕
SERVER01

from NETPLUS-ADMIN.

Verify:

Source MAC

Destination MAC

Protocol

Source IP

Destination IP

62. Troubleshooting Scenario — Endpoint Up but Switch Port Down

Symptoms:

Endpoint Interface:
Appears Enabled

Switch Interface:
Down

Investigate:

Virtual Cable

Physical Cable

Switch Port State

NIC

Hypervisor Attachment

63. Troubleshooting Scenario — Switch Port Up but No IP Connectivity

If:

Port:
Up

but:

Ping:
Fails

Layer 1/2 connectivity may be present.

Investigate next:

IP Address

Subnet Mask

ARP

Firewall

VLAN

64. Troubleshooting Scenario — MAC Learned but Ping Fails

If the switch has learned:

SERVER01 MAC → Port 3

this indicates Layer 2 frames are reaching the switch from SERVER01.

But IP communication can still fail because of:

Wrong IP

Wrong Subnet Mask

Firewall

Duplicate IP

Application Problem

Do not stop troubleshooting at the MAC table.

65. Troubleshooting Scenario — No MAC Learned

If no MAC is learned on a port:

No Frames Received

may be occurring.

Investigate:

Port Down

Endpoint Down

Cable Disconnected

Wrong Virtual Switch

NIC Disabled

No Traffic Generated

66. Use Layered Troubleshooting

Use:

Layer 1
Link Present?
      ↓
Layer 2
MAC Learned?
      ↓
Layer 3
IP Correct?
      ↓
Layer 4+
Service Working?

67. Create the Switch Baseline

Document:

Switch Name:
NETPLUS-SW01

Management Address:
<if configured>

Ports Used:
1–3

VLAN:
Default / Lab VLAN

MAC Aging:
<value>

Port Status:
<details>

68. Mission Challenge — MAC Learning

Clear dynamic MAC entries.

Generate traffic:

ADMIN → CLIENT01

CLIENT01 → SERVER01

SERVER01 → ADMIN

After each exchange, record the MAC table.

Your goal is to demonstrate:

Source Traffic
      ↓
MAC Learning

69. Mission Challenge — Forwarding Decision

Given:

MAC-A → Port 1

MAC-B → Port 2

MAC-C → Port 3

A frame arrives:

Incoming:
Port 1

Source:
MAC-A

Destination:
MAC-C

Answer:

Forward to Port 3

70. Mission Challenge — Unknown Unicast

A frame arrives:

Incoming:
Port 1

Source:
MAC-A

Destination:
MAC-X

MAC-X is not in the table.

Expected:

Flood to other ports in the VLAN

71. Mission Challenge — Broadcast

Frame destination:

ff:ff:ff:ff:ff:ff

Expected:

Flood to all other ports in same VLAN

72. Mission Challenge — Collision Domains

Given:

3 endpoints
connected to
3 separate switch ports

How many collision domains?

Answer:

assuming normal switched Ethernet operation.

73. Mission Challenge — Broadcast Domains

All three switch ports are in the same VLAN.

How many broadcast domains?

Answer:

74. Mission Challenge — Interface Troubleshooting

SERVER01 becomes unreachable.

You discover:

Switch Port 3:
Administratively Down

Your resolution:

Re-enable Port
      ↓
Verify Link
      ↓
Verify MAC Learning
      ↓
Verify IP Connectivity

75. Mission Challenge — Host Move

Move CLIENT01 to another switch port.

Record:

Old Port:

New Port:

MAC Before:

MAC After:

Time to Relearn:

Connectivity Result:

76. Create the Lab Workspace

On NETPLUS-ADMIN:

mkdir -p ~/NetworkPlus-Labs/LAB06/{Captures,Screenshots,Configs,Notes}

Create:

touch ~/NetworkPlus-Labs/LAB06/Notes/lab06-notes.md

77. Save Switch Information

Where supported, save outputs such as:

show mac address-table

show interfaces status

show interfaces

Store in:

~/NetworkPlus-Labs/LAB06/Configs/

78. Document Your Findings

Use:

# LAB06 — Ethernet Switching Fundamentals

## Switch

Name:
NETPLUS-SW01

## Port Mapping

### Port 1

Device:
MAC:
Status:
Speed:
Duplex:

### Port 2

Device:
MAC:
Status:
Speed:
Duplex:

### Port 3

Device:
MAC:
Status:
Speed:
Duplex:

## MAC Address Table

ADMIN:

CLIENT01:

SERVER01:

## MAC Learning

Describe how each MAC was learned.

## Known Unicast

Source:

Destination:

Incoming Port:

Outgoing Port:

## Unknown Unicast

Observed / Conceptual Behavior:

## Broadcast

Broadcast MAC:

Forwarding Behavior:

## Collision Domains

Count:

Explanation:

## Broadcast Domains

Count:

Explanation:

## Troubleshooting

### Disabled Port

Problem:

Root Cause:

Fix:

Verification:

### Host Move

Old Port:

New Port:

MAC Relearned:

## Final Assessment

Summarize how NETPLUS-SW01 learns and forwards Ethernet traffic.

79. Evidence to Capture

Capture:

01-switch-topology.png

02-endpoint-mac-addresses.png

03-empty-mac-table.png

04-admin-mac-learned.png

05-client-mac-learned.png

06-server-mac-learned.png

07-complete-mac-table.png

08-known-unicast-frame.png

09-arp-broadcast.png

10-broadcast-destination-mac.png

11-interface-status.png

12-speed-duplex.png

13-port-down.png

14-ping-failure.png

15-port-restored.png

16-connectivity-restored.png

17-host-port-move.png

18-mac-relearned.png

19-switch-baseline.png

20-final-topology.png

80. Validation Checklist

Topology

NETPLUS-SW01 created
ADMIN connected
CLIENT01 connected
SERVER01 connected
All interfaces verified

MAC Learning

Endpoint MAC addresses recorded
Dynamic MAC table reviewed
MAC table cleared safely
ADMIN MAC learned
CLIENT01 MAC learned
SERVER01 MAC learned
Source-MAC learning understood

Forwarding

Known unicast forwarding understood
Unknown unicast flooding understood
Broadcast flooding understood
Frame filtering understood
Forwarding decision process documented

Layer 2 Concepts

Collision domains understood
Broadcast domains understood
Switch vs hub understood
Unicast understood
Broadcast understood
MAC aging understood
Dynamic vs static MAC concepts understood

Interfaces

Interface status reviewed
Speed reviewed
Duplex reviewed
Full duplex understood
Auto-negotiation understood
Administratively down state understood

Troubleshooting

Disabled-port scenario completed
Port restored
Cable/virtual-link scenario understood
Missing-MAC scenario investigated
MAC-learned-but-IP-fails scenario understood
Host move completed
MAC relearning observed

Monitoring

Wireshark Ethernet frames reviewed
ARP broadcast captured
Source/destination MAC verified
Port-mirroring concept understood

Documentation

Port map created
MAC table documented
Switch baseline created
Evidence captured
Lab notes completed

81. Mission Review

In this mission, you moved from understanding individual Ethernet frames to understanding how a switch handles them.

The switching process is:

Ethernet Frame Arrives
        ↓
Learn Source MAC
        ↓
Inspect Destination MAC
        ↓
Known?
   ┌────┴────┐
  Yes        No
   ↓          ↓
Forward      Flood
   ↓
Correct Port

Broadcast traffic follows:

Broadcast Frame
      ↓
Switch
      ↓
Flood Within VLAN

You also learned the important distinction:

Switch Port
      ↓
Separate Collision Domain

while:

Multiple Ports in Same VLAN
      ↓
Same Broadcast Domain

The key lesson is:

A switch makes intelligent Layer 2 forwarding decisions by learning where source MAC addresses are located and then using its MAC address table to send known unicast traffic only where it needs to go.

Skills Developed

After completing this mission, you should be able to:

explain Ethernet switching
identify switch ports
read a MAC address table
explain source-MAC learning
explain known unicast forwarding
explain unknown unicast flooding
explain broadcast forwarding
explain frame filtering
distinguish hubs and switches
identify collision domains
identify broadcast domains
understand full and half duplex
understand speed and duplex negotiation
inspect interface states
recognize administratively down ports
understand MAC aging
understand MAC moves
recognize MAC flapping conceptually
troubleshoot basic switching problems

What’s Next?

Lab 07 — VLAN Configuration and Inter-VLAN Connectivity

You now have one switched network:

ADMIN
CLIENT01
SERVER01
      ↓
Same Switch
      ↓
Same Broadcast Domain

The next mission introduces VLANs to logically separate that network.

You will configure:

VLAN IDs
access ports
VLAN membership
VLAN segmentation
broadcast-domain separation
802.1Q trunking
tagged Ethernet frames
native VLAN concepts
VLAN verification
inter-VLAN routing
default gateways
router-on-a-stick concepts
Layer 3 switch concepts
VLAN mismatch troubleshooting
trunk troubleshooting

The progression becomes:

Ethernet Switch
      ↓
One Broadcast Domain
      ↓
VLANs
      ↓
Multiple Broadcast Domains
      ↓
802.1Q Trunks
      ↓
Layer 3 Routing
      ↓
Inter-VLAN Connectivity

➡️ Next: Lab 07 — VLAN Configuration and Inter-VLAN Connectivity