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New Member

VLAN and DHCP

Freinds,

I have a scenario here where i have 2 diffrent VLAN configured( VLAN 1 and VLAN 2), And i have a DHCP Server on third VLAN, I have VLAN trunking and able to reach my DHCP from both the VLANS,

Now the issue is that in DHCP i have created 2 Scopes of Diffrent Subnets, i want that Hosts of Each VLAN to get IP from there Respective Subnet from the DHCP, For Ex. if VLAN 1 has IP range of some Subnet A for which i have a Scope in DHCP also ,then Host of VLAN 1 should get IP from this particular scope of DCHP, And the same should happen for VLAN 2 for which some Subnet B scope has been created in DHCP.

Is this possible ?? If yes then How

Maneesh

4 REPLIES
New Member

Re: VLAN and DHCP

what switch do u use? is it a layer 3?

New Member

Re: VLAN and DHCP

Ya its a Layer 3 Switch.

New Member

Re: VLAN and DHCP

Yes,

1st - you have to configure the trunk in dot1q (802.1q)

2nd - The DHCP Server needs a NIC that supports 802.1q and the DHCP service must support it also....or be fooled as 2 distinct NIC's..

regards,

PT

New Member

Re: VLAN and DHCP

Yes,

You need to put an IP helper address of your DHCP server on each of the Vlan interfaces that you define in order for the DHCP broadcasts to be forwarded to the DHCP Server.

For example:

interface Vlan1

description Native Vlan

ip address “Subnet A”

ip helper-address “DHCP Server IP Address”

!

interface Vlan2

description

ip address “Subnet B”

ip helper-address “DHCP Server IP Address”

!

interface Vlan3

description Vlan with DHCP Server

ip address “Subnet C”

Hope this is what you were looking for....

Geoff

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