subinterfaces help needed

hi guys,

i am stuck on lab excersise for the WAN moduel of ccna. i need to create subinterfaces on the fa interfaces but dont know how to do this without assigning a vlan to it. below is the addressing table for the topology.

it seems like there are 3 vlan 10, 20, 30 so for example on R1 fa0/1.10 would go in vlan 10 but i dont understand what to do with fa0/1.12 or fa0/1.13 as it seems like it does not belong in a vlan. hope you can help

R1
Fa0/1.10
192.168.10.1
255.255.255.0

Fa0/1.12
10.12.12.1
255.255.255.0

Fa0/1.13
10.13.13.1
255.255.255.0

S0/0/0
10.1.1.1
255.255.255.252

R2

Fa0/1.12
10.12.12.2
255.255.255.0

Fa0/1.20
192.168.20.1
255.255.255.0

S0/0/0
10.1.1.2
255.255.255.252

S0/0/1
10.2.2.1
255.255.255.252

R3

Fa0/1.13
10.13.13.3
255.255.255.0

Fa0/1.30
192.168.30.1
255.255.255.0

S0/0/1
10.2.2.2
255.255.255.252

S1
VLAN10
192.168.10.2
255.255.255.0
192.168.10.1

S2
VLAN20
192.168.20.2
255.255.255.0
192.168.20.1

S3
VLAN30
192.168.30.2
255.255.255.0
192.168.30.1

PC1
NIC
192.168.10.10
255.255.255.0
192.168.10.1

PC3
NIC
192.168.30.10
255.255.255.0
192.168.30.1

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Comments

BroadcastStorm

Your subinterfaces doesn't need to match the VLAN number, although it is good to match it so it's uniform etc.

roonie

BroadcastStorm wrote: »

Your subinterfaces doesn't need to match the VLAN number, although it is good to match it so it's uniform etc.

do subinterfaces have to be assigned to a vlan number? and what ever number i assigned then to would i then need to create a vlan on the switch for them

BroadcastStorm

roonie wrote: »

do subinterfaces have to be assigned to a vlan number? and what ever number i assigned then to would i then need to create a vlan on the switch for them

Your assigning a sub network under the sub-interface your trying to do ROAS, VLAN can belong to any subnet example VLAN 2 can either belong to 192.168.2.x or 172.16.2.x

The sub-interface must include an encapsulation command followed by vlan number example, encapsulation dot1q 20 this is the key command of pointing the subinterface to a VLAN, then your subnet address.

Yes, you'll need to create the vlans in your switch,

wbosher

The encapsulation dot1q xx command is the important one in regards to vlans on an interface. The sub-interface can be whatever you like, although it is easier if they are the same.

roonie

i get it now thanks guys

rogue2shadow

wbosher wrote: »

The encapsulation dot1q xx command is the important one in regards to vlans on an interface. The sub-interface can be whatever you like, although it is easier if they are the same.

Also make sure to add "native" to the end of the encapsulation dot1q xx command for the native vlan on the router for the network (ie. Management vlan).