Basic configuration: cisco switch configuration vlan (2)

VLAN settings on a layer-3 Switch

1) Method 1: General Configuration

 
 

  
  
Switch# configure terminal  
  
  
 
  
  
Switch(config)# vlan 20  
  
  
 
  
  
Switch(config-vlan)# name test20  
  
  
 
  
  
Switch(config-vlan)#ip address 1.1.1.1 255.255.255.0  
  
  
 
  
  
Switch(config-vlan)# end 
 
 

Method 2: enable VLAN configuration:

 
 

  
  
Switch # vlan database // enter the VLAN configuration status
  
  
 
  
  
Switch (vlan) # vlan 20 name test20 // Add the vlan id and VLAN name
  
  
 
  
  
Switch (vlan) # exit update the VLAN database and exit
 
 

2) allocate a port to a VLAN

 
 

  
  
Switch # configure terminal
  
  
 
  
  
Switch (config) # interface fastethernet0/1
  
  
 
  
  
Switch (config-if) # switchport mode access // defines the working mode of the L2 port as the access mode
  
  
 
  
  
Switch (config-if) # switchport access vlan 2 // assign a port to a VLAN
  
  
 
  
  
Switch (config-if) # end
  
  
 
  
  
Switch #
 
 

3) Configure VLAN Trunks

 
 

  
  
Switch # configure terminal
  
  
 
  
  
Switch (config) # interface fastethernet0/4
  
  
 
  
  
Switch (config-if) # switchport mode trunk
  
  
 
  
  
Switch (config-if) # switchport trunk encapsulation dot1q
  
  
 
  
  
Switch (config-if) # end
  
  
 
  
  
Appendix: switchport trunk encapsulation {isl | dot1q | negotiate} // configure trunk to encapsulate ISL or 802.1Q or automatically negotiate
 
 

Switchport mode {dynamic {auto | desirable} | trunk} is generally not used). Configure the layer-2 trunk mode. Dynamic auto-automatically negotiate whether it is a trunk; dynamic desirable-set the port to trunk if the peer port is trunk, desirable, or automatic mode; trunk-set the port to the forced trunk mode, regardless of whether the other port is trunk)

4) define the VLAN allowed by the trunk

 
 

  
  
Switch (config) # interface fastethernet0/1
  
  
 
  
  
Switch (config-if) # switchport trunk allowed vlan remove 2 // configure the VLAN allowed by the trunk
  
  
 
  
  
Switch (config-if) # end
  
  
 
  
  
Appendix: switchport trunk allowed vlan {add | all | unique T | remove} vlan-list
 
 

5) Configure Native VLAN802.1q)

 
 

  
  
Switch (config-if) # switchport trunk native vlan-num
  
  
 
  
  
// The trunk port that encapsulates 802.1q can accept tagged and unlabeled data streams. The switch transfers unlabeled data streams to the native vlan, by default, the native VLAN is VLAN 1. Use the no switchport trunk native vlan port configuration command to return to the default status.
 
 

6) configure a group of Ports

 
 

  
  
4006 # configure terminal
  
  
 
  
  
4006 (config) # interface range fastethernet2/1-5
  
  
 
  
  
4006 (config-if-range) # no shutdown
  
  
 
  
  
// Note: a space must be added between the port numbers. For example, interface range fastethernet 2/1-5 is valid, while interface range fastethernet 2/1-5 is invalid.
  
  
 
  
  
The following example shows how to configure groups with different port types using commas:
  
  
 
  
  
4006 # configure terminal
  
  
 
  
  
4006 (config) # interface range fastethernet2/1-3, gigabitethernet3/1-2
  
  
 
  
  
4006 (config-if-range) # no shutdown
 
 

7) Other Common commands

 
 

  
  
Duplex {auto | full | half}
  
  
 
  
  
// Set full or half duplex.
  
  
 
  
  
Speed {10 | 100 | 1000 | auto | nonegotiate}
  
  
 
  
  
// Note: 1000 only works on Gigabit ports. The GBIC module only works at 1000 Mbps. nonegotiate can only use 1000BASE-SX,-LX, and-zx gbic on these GBIC.
  
  
 
  
  
Copy running-config startup-config
  
  
 
  
  
// Save settings
 
 

8) Configure EtherChannel

Several Ethernet ports are bound to an independent Logical Link. For example, you can bind a 4006 vswitch to a maximum of eight compatible ports with the same speed on any 4006 module. Each Ethernet channel has a port-channel port number. To bind an Ethernet channel, a logical port-channel is generated. The configuration under the logical port may affect the physical port bound with it, however, the configuration of physical ports does not affect the configuration of logical ports.

1) layer-3 Ethernet channel logical port-channe) Configuration

 
 

  
  
Switch # configure terminal
  
  
 
  
  
Switch (config) # interface port-channel 1 // create a logical port
  
  
 
  
  
Switch (config-if) # ip address 172.32.52.10 255.255.255.0
  
  
 
  
  
Switch (config-if) # end
 
 

2) layer-3 physical port configuration

 
 

  
  
Switch # configure terminal
  
  
 
  
  
Switch (config) # interface range fastethernet 5/4-5 (Note: spaces are required)
  
  
 
  
  
Switch (config-if) # no switchport // change the port to a layer-3 Interface
  
  
 
  
  
Switch (config-if) # no ip address // confirm that the interface is not configured with an ip address
  
  
 
  
  
Switch (config-if) # channel-group 1 mode desirable
  
  
 
  
  
Switch (config-if) # end
  
  
 
  
  
Appendix: Switch (config-if) # channel-group port_channel_number mode {auto | desirable | on} // Add the physical port to an Ethernet channel and determine the PagP mode.
 
 

3) layer-2 Ethernet Channel Configuration

 
 

  
  
Switch # configure terminal
  
  
 
  
  
Switch (config) # interface range fastethernet 5/6-7 (Note: spaces are required)
  
  
 
  
  
Switch (config-if-range) # channel-group 2 mode desirable
  
  
 
  
  
Switch (config-if-range) # end
  
  
 
  
  
Switch # show running-config interface port-channel 2
  
  
 
  
  
Building configuration...
  
  
 
  
  
Current configuration:
  
  
 
  
  
!
  
  
 
  
  
Interface Port-channel2
  
  
 
  
  
Switchport access vlan 10
  
  
 
  
  
Switchport mode access
  
  
 
  
  
End
  
  
 
  
  
Switch #
 
 

The configurations of VLAN on a layer-3 Switch have been described.

1. Typical VLAN-VPN Configuration
2. Typical configurations of multicast VLAN
3. Port-based VLAN Configuration Guide
4. Basic configuration: cisco switch configuration vlan1)
5. Basic configuration: cisco switch configuration vlan2)