The network lab contains two Catalyst 2950T24 switches named Maryland and California, and one Catalyst 2950G switch named Virginia. The 2950T24 switches each have 24 10/100 Base T ports and two 10/100/1000 Base T ports. The 2950G switch currently does not have its two 10/100/1000 Base T ports installed. VLANs are used to segment the network and define which ports belong to which VLANs through configuration commands.

1. VLAN 1
VLAN Configuration
The network lab has two Catalyst 2950T24 switches, with
names Maryland and California, and one Catalyst 2950G
Switch with name Virginia.
- References:
http://www.cisco.com/en/US/products/hw/switches/ps4916/pro
ducts_configuration_guide_chapter09186a008017e532.html
− The two Catalyst 2950T24’s in the network lab, each
has 24 10/100 Base T ports, and two 10/100/1000 Base T
ports i.e., gi0/1 and gi0/2.
− For Catalyst 2950G (i.e, Virginia), the two
10/100/1000 Base T ports are currently not installed
− The 24 10/100 Base T ports are: fa0/1, fa0/1,fa0/2, …
fa0/24
− Two 10/100/1000 Base T ports are: gi0/1 and gi0/2
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2. VLAN 2
♦ All the Cisco switches has two operational modes
− User Exec Mode :
When a user first establishes the connection with the
switch, and enter the password, the switch is in ‘User
EXEC Mode’, and the prompt is ‘>’.
− Privileged Mode: when user enter the command
‘enable’ and supply the password, it enters the
privileged mode, and the prompt is ‘#’
− Only in privileged mode, a user can enter configuration
mode; to enter configuration mode, user must enter the
command ‘config t’
♦ Configuration commands
− The following configuration commands explains how to
define a vlan name, assigning a static-access ports to a
VLAN, or deleting a VLAN.
− A VLAN port can be either in permanent trunk mode,
or in non-trunking mode as access
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3. VLAN 3
Configure
Privileged Mode
User Mode enable Mode Config t
Router(config)#
Router> Router#
end
disable
end
Ctrl-Z interface
Router(config-if)
router
Router(config-router)
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4. VLAN 4
♦ What is a Trunk?
• A Trunk is a point-to-point link that transmit and receive
traffic between switches or switch and routers.
• Trunks carry the traffic of multiple VLANs and can
extend VLANs across an entire network
I.Define VLAN name
step command purpose
1 Config t Enter global configuration mode
2 Vlan vlan-id Enter a VLAN ID
3 Name vlan-name Enter a name for the VLAN
4 end Return to privileged mode
5 Show vlan {name | id vlan-id } Verify your entries
6 copy running-cnofig startup- Save the configuration in the switch
config or wr mem configuration file
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5. VLAN 5
II.Insert interface ports to VLAN
Step Command Purpose
1 Config terminal Enter global configuration mode
2 Inter interface-id Enter the interface to be added to the
VLAN
3 Switchport mode access Define the VLAN membership mode for
the port
4 Switchport access vlan Assign the port to a VLAN
Vlan-id
5 end Return to privileged EXEC mode
6 Show config or running-config Verify the VLAN membership mode of
interf interface-id the interface
7 Sh interf interface-id switchport Verify your entries in the Administrative
mode and the access mode VLAN field
8 Copy running-config startup- Save your entires in the configuration
config file
Or wr mem
III.Deleting a VLAN
step command purpose
1 Config t Enter global configuration mode
2 No vlan vlan-id Remove the VLAN by entering the
VLAN-ID
3 end Return to privileged mode
4 Sh vlan brief Verify the VLAN removed
5 copy running-config startu-config Save the configuration in the switch
or wr mem startup configuration file
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6. VLAN 6
♦ The 26 interface ports of Catalyst 2950 T24 are:
• Interface fa0/i, where i= 1. 24 are the 24 10/100 Base T
ports
• Interface gi0/1 or 0/2 are the two 10/100/1000 Base T
ports
♦ The 24 ports of Catalyst 2950G Switch are:
• Interface fa0/i, where i= 1. 24
♦ Switchport mode access – interface is put into permanent
nontrunking mode
♦ Switchport mode trunk - interface into permanent
trunking mode
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7. VLAN 7
Examples of VLAN configuration
California#sh vtp status
/* show the vtp status */
California#sh vlan /*to show all the vlans configured */
California#config t /* this command cause the switch to enter configuration mode, when
all configuration is completed, enter either Ctrl^z or end to return to privileged
EXEC mode */
California(config)#vlan 10 name vlan10
/* defines name of vlan 10 as vlan10
California(config)#int fa0/1
California(config)#switchport mode access
California(config)#switchport access vlan 10 /* set port fa0/1
into vlan 10 */
California(config)#int fa0/2
California(config)#switchport mode access
California(config)#switchport access vlan 10
California(config)#int fa0/3
California(config)#switchport mode access
California(config)#switchport access vlan 10
/* at this point, vlan 10 has 3 members i.e., fa0/1, fa0/2 and fa0/3 */
California(config)#vlan 20 name vlan20
California(config)#int fa0/5
California(config)#switchport mode access
California(config)#switchport access vlan 20
California(config)#int fa0/6
California(config)#switchport mode access
California(config)#switchport access vlan 20
California(config)#int fa0/7
California(config)#switchport mode access
California(config)#switchport access vlan 20
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8. VLAN 8
California(config)#int fa0/8
California(config)#switchport mode access
California(config)#ctrl-Z
California# /*return to privileged mode */
/* At this poing vlan 20 has 4 members i.e.,
fa0/5, fa0/6, fa0/7 and fa0/8 */
California(config)#int gi0/2
California(config)# switchport mode trunk
/* this will put the port gi0/2 to be in permanent
trunking mode */
California(config)#switchport access vlan 40
/* put int gi0/2 into vlan 40 */
California(config)#switchport access vlan 20
California(config)#end or ctrl-Z
/* return to privileged mode */
California#wr mem or copy running-config strtup-config
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