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ISP - DHCP - Subinterfaces

aacisco123
Level 1
Level 1
I have an interface connected to an isp which is the DHCP server. I need to create two subinterfaces that receive two different IP addresses from the ISP. In one subinterface I will do NAT and the other will not. 
What would be the best solution to receive IP addresses from the ISP?
interface G0
no ip address

interface g0/0.2
encapsulation dot1q 2
ip address dhcp
¿?

ip vrf forwarding OUTSIDE 1
 interface g0/0.3
encapsulation dot1q 3 ip address dhcp
¿?
ip nat outside
ip vrf forwarding OUTSIDE 3
 ! 

interface vlan 3
ip vrf forwarding OUTSIDE3

ip nat inside
ip address xxx
THANK IN ADVANCE 
2 Replies 2

Hello,

I think you need the 'ip helper-address' command on the subinterfaces, with the IP address being the one of the DHCP server...

Hi,

Do you know if the provider is using your MAC addresses as identifier? If they are, you could configure the following command under your sub interfaces. Assuming the ISP has a local dhcp pool and the configuration is correct and the dhcp pools are different to avoid overlapping.

int g0/0.2
ip address dhcp
ip address dhcp client-id g0/0.2

int g0/0.3
ip address dhcp
ip address dhcp client-id g0/0.3

Could you please confirm the MAC addresses displayed on the sub-interfaces? I have not used it with subinterfaces before but you can try. 




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