CCNA-Notes/18. VLAN (Part 3).md

id, aliases, tags

id	aliases	tags
1778493954-IJHJ	VLAN (Part 3)

VLAN (Part 3)

Native VLAN on a router (ROAS)

There 2 methods for configuring the native VLAN on a router:

R1(config)# int g0/0.10
R1(config-subif)#encapsulaton dot1q *vlan-id* native

Configure the IP address for the native VLAN on the router's physical interface (the command is not necessary)

R1(config)# int g0/0.10
R1(config-subif)#ip address 192.168.1.62 255.255.255.192

Layer 3 (Multilayer) switches

• A multilayer switch is capable of both switching and routing.
• It is 'Layer 3 aware'
• You can assign IP addresses to its interfaces, like a router.
• You can create virtual interfaces for each VLAN, and assign IP addresses to those interfaces.
• You can configure routes on it, just like a router.
• it can be used for inter-VLAN routing

Inter-VLAN routing via SVI

• SVIs (Switch Virtual Interfaces) are the virtual interfaces you can assign IP addresses to in a multilayer switch.
• Configure each PC to use the SVI (Not the router) as their gateway address.
• To send traffic to different subnets/VLANs, the PCs will send traffic to the switch, and the switch will route the traffic

the command to enable Layer 3 routing on the switch is

SW2(config)#ip routing

## this configure the interface as a 'routed port'
## (Layer 3 port, not Layer 2 /switchport)
SW2(config)#interface g0/1
SW2(config-if)#no switchport

## then you can configure an IP address on the interface like a regular router interface
SW2(config-if)#ip address 192.168.1.193 255.255.255.252

## then you can configure the default route
SW2(config-if)#ip route 0.0.0.0 0.0.0.0 192.168.1.194

To configure SVI you can assign ip address to each vlan

SW2(config)#interface vlan10
SW2(config-if)#ip address 192.168.1.62 255.255.255.192
SW2(config-if)#no shutdown
SW2(config)#interface vlan20
SW2(config-if)#ip address 192.168.1.126 255.255.255.192
SW2(config-if)#no shutdown
SW2(config)#interface vlan30
SW2(config-if)#ip address 192.168.1.190 255.255.255.192
SW2(config-if)#no shutdown

1. The Vlan must exist on the switch
2. The swithc must have at least one access port in the VLAN in an up/up state, AND/OR one trunk port that allows the VLAN that is in an up/up state
3. The VLAN must not be shutdown (you can use the shutdown command to disable a VLAN)
4. The SVI must not be shutdown (SVIs are disabled by default)

Review

• Native VLAN on a router
• Wireshark analysis
• Layer 3 Switching/multilayer Switching

next lesson

• DTP (Dynamic Trunking Protocol)
• VTP (VLAN trunking Protocol)