VLANs on routers

Question 1

Do routers negotiate trunking?

Answer 1

No, all trunking must be configured manually

Question 2

If a router has multiple tagged subinterfaces on a physical interface connected to a switch, should the switch port be configured as trunk or access?

Answer 2

The switch port should be configured as a trunk

Question 3

Configure a router interface (gi1/0) to use a subinterface in vlan 11 with the most common encapsulation, with an IP address of 10.22.33.1/24

Answer 3

conf t
interface gi1/0.11
encapsulation dot1q 11
ip address 10.22.33.1 255.255.255.0

Question 4

Assuming a router has gi2/2.15 configured, change it so that vlan 15 is the native vlan

Answer 4

conf t
int gi2/2.15
encapsulation dot1q 15 native

Question 5

In the below output, which line defines that vlan tagging that will be used?

conf t
interface gi1/0.11
encapsulation dot1q 11
ip address 10.22.33.1 255.255.255.0

Answer 5

encapsulation dot1q 11

Question 6

What alternative encapsulation can be used if dot1q is not an option?

Answer 6

isl

Question 7

What are the 2 methods on a router for specifying untagged traffic?

Answer 7

1. Put an IP address on the main interface.

2. Put an IP address on a subinterface, and add the keyword “native” when specifying the encapsulation/vlanid.

Question 8

Command on a router to show the native vlan.

Answer 8

show vlans [vlanid]

Question 9

Command on a router to show all trunks and their encapsulation

Answer 9

show vlans