New subnet not getting DHCP address

[ksaveit]

Hello so I am trying to migrate to a new subnet. I would like to get the new subnet and old coexisting so I can switch over in stages. I have an asa 5516 and the original subnet is 192.1 the new is 10.128. I have set up DHCP relay on the 10.128 interface and still can't get an IP address from DHCP. Traffic is flowing fine between the interfaces if I statically assign an ip on the 10.128. I think the issue is tied to the asa but not fully sure. Any help would be appreciated! I will attach my config. Thanks

[Georg Pauwen]

Hello,

before anything else, I assume you 'no shut' the interface ?

interface GigabitEthernet1/8
shutdown
nameif NewSub
security-level 100
ip address 10.128.128.20 255.255.240.0

[Georg Pauwen]

Hello,

the config doesn't look right. Your DHCP server is 192.1.1.6, so it is behind interface 'inside' BVI1. That means, the config should be:

dhcprelay server 192.1.1.6 inside
dhcprelay enable NewSub
dhcprelay setroute NewSub
dhcprelay timeout 60

[ksaveit]

I get the following error when sending cmd dhcprelay server 192.1.1.6 inside

Result of the command: "dhcprelay server 192.1.1.6 inside"

ERROR: % Ambiguous command: "dhcprelay server 192.1.1.6 inside"

[Georg Pauwen]

Hello,

what are your options when you type:

dhcprelay server 192.1.1.6 ?

[ksaveit]

This is what i get thanks 

Result of the command: "dhcprelay server 192.1.1.6 ?"

configure mode commands/options:
Available interfaces on which the DHCP server can be found:
Azure-VTI01 Name of interface Tunnel30
NewSub Name of interface GigabitEthernet1/8
inside_5 Name of interface GigabitEthernet1/6
inside_6 Name of interface GigabitEthernet1/7
outside Name of interface GigabitEthernet1/1

[Georg Pauwen · Accepted solution]

Hello,

see the enhancement request. DHCP relay server is currently not supported on BVI interfaces. Your only option is to move the DHCP server to another interface...

ENH: Add support for DHCP Relay for Integrated Routing and Bridging

CSCvh32636

Description

Symptom:
DHCP relay is currently not supported on an L3 BVI interface using ASA or FTD integrated routing and bridging. The IRB functionality was released in ASA 9.7(1).

Conditions:
Attempting to configure DHCP relay on an L3 BVI interface using ASA or FTD integrated routing and bridging

Workaround:
N/A - this is an enhancement request to include this functionality.

[ksaveit]

Is it possible to just remove the bvi? 

[Georg Pauwen]

It looks like you have several physical interfaces bound to that BVI. I don't know what your topology looks like, or if you can change the IP address of the BVI, or remove it altogether ?

[ksaveit]

I was able to get it working by setting up my spare ASA without the BVI settings. Thanks for all the help!

[ksaveit]

Hey thanks for the quick response! Yes it is currently set to no shut. 

[paul driver]

Hello
Is this is a new setup regards dhcp relay as i dont see anything related to any other current dhcp relay just that one entry pointing to a quite large subnet interface?

So where does you dhcp server reside, out of what interface?

You also have NAT enabed for every interface, No dynamic or default routing or any specific route in your configuration to allow the dhcp traffic to be routed to the relay address?