Configure IPv4 DHCP with trunk port

[bi13hy]

Hi All,

I am currently stuck trying to configure DCHP  over a trunk port.

I have completed the DHCP procedure but I'm unsure how to assign an IP address to a trunk port?

Any help appreciated.

[Flavio Miranda]

Add the zipped .pkt and devices password.  I can help you.

But, antecipating, you can assign IP to a trunk. In order to assign IP address to an Interface, you need to run the command:

no switchport

The interface need to be in Layer 3 mode. Trunk is essencially, a Layer 2 mode interface

What you can do is assign IP address to a port-channel.

[bi13hy]

Thank you Falvio for your response.

Correct me if I'm wrong but am i typing the incorrect subnet mask here to encapsulate my router to access VLAN 4 addresses? I have used the VLAN 4 subnet I.D but says it is overlapping? Thoughts please?

[Flavio Miranda]

For some reason I did not see any file. Can you attach here please.

[bi13hy]

Thank you for your response.

I have established I need to create subinterfaces on my router for VLAN's. 

However when I enter VLAN ip and subnet it rejects it. 

Thoughts please?

[Jon Marshall]

The IPs you are entering are the subnet addresses ie. 172.16.64.0 and 172.16.128.0  which is why it is showing an error. 

Use the first IP address available ie. 172.16.64.1 and 172.16.128.1 (or any other IP from the subnet if you want). 

Jon

[bi13hy]

Hi Jon, 

Thank you for your response. 

When i assign different subnets, it suggests my mask is overlapping with go/o but I have adjusted this?

I have attached 2 screen shots, one with an overview of the task and the latter my coding.

[Jon Marshall]

You seem to have posted the same as before ie. you have not updated the IPs you are using. 

What is the IP and subnet mask on gi0/0 ? 

Also that is a very large topology you have, if you are learning networking best to start small and then build up. 

Jon

[bi13hy]

Hi Jon,

For example i used a different ip address but same subnet as VLAN public address /20 but states it overlaps with 172.16.64.0 /16 gigabitethernet 0.0. However that IP address is 172.16.44.9 /16. 

This topology is for an assignment annoyingly.

Thoughts?

[Jon Marshall]

Can you just post the IPs you are trying to use with the subnet masks where it is saying they are overlapping. 

Jon

[bi13hy]

IP addresses

Network IP 172. 16. 0.0 /16

Vlan 2 172.16.128.0/20

Vlan 3 172.16.64.0/19

Router Interface g0/0 IP 172.16.144.9 255.255.0.0

Router interface g0/1- Trunk port-Subnet I.D's  Vlan2:128.1 Vlan3: 64.1 

I have coded the following:

interface go/1.2

encapsulation dot1q 2

ip address 172.16.128.3 255.255.240.0

then says....

172.16.64.0 overlaps with gigabitethernet 0/0

Thoughts please

[Jon Marshall]

Yes because gi0/0 is 172.16.0.0/16 which covers both 172.16.64.0/19 and 172.16.128.0/20. 

So you need to change the subnet mask of gi0/0 if you want to use 172.16.x.x IPs on all the interfaces eg. /24 would be fine but there are a lot of options you could choose. 

Jon

[bi13hy]

Thank you for your help. Problem solved. 

[Georg Pauwen]

Hello,

what they most likely want you to do is configure the link between R8 and S8 as a trunk with subinterfaces on R8. The configuration of R8 would look something like below:

R8

interface GigabitEthernet0/0
description Trunk to S8
!
interface GigabitEthernet0/0.3
description Vlan3 Subinterface
encapsulation dot1q 3
ip address 192.168.3.1
!
interface GigabitEthernet0/0.4
description Vlan4 Subinterface
encapsulation dot1q 4
ip address 192.168.4.1

[bi13hy]

Thank you Georg for your response.

Following your guidance I still failed to complete a DHCP.

I used the default VLAN 4  address  172.16.0.0 255.255.192.0

Any suggestions welcome please?