Re: Second DHCP server seems to be ignoring requests

I would suspect it is either the fact the DHCP server hasn't been authorized
yet in AD -or- the clients aren't on the same subnet as the DHCP server and
a dhcp helper (Relay on a router) on the remote subnets hasn't been
configured.

--
Paul Bergson
MVP - Directory Services
MCTS, MCT, MCSE, MCSA, Security+, BS CSci
2008, 2003, 2000 (Early Achiever), NT4
Microsoft's Thrive IT Pro of the Month - June 2009

http://www.pbbergs.com

Please no e-mails, any questions should be posted in the NewsGroup This
posting is provided "AS IS" with no warranties, and confers no rights.

"tdnnash25" <> wrote in message
news:37731dcb-32a4-4277-987e-...
>I have a Domain Controller that is doing DHCP but we are going to be
> taking it down. Thus, I am tasked with getting DHCP, DNS, etc
> configured on Server2.
>
> Server 2 is a domain controller. I used netsh to export the DHCP
> database from Server1 and likewise used it to import the database on
> Server2. I then authorized Server2 as a DHCP server.
>
> The problem is when I stop the DHCP service on Server1 and attempt to
> get a DHCP address on a client PC, I don't get one. As soon as I
> restart the DHCP service on Server 1, I do. I ran Wireshark on
> Server2 and it sees the DHCP broadcasts coming in, but nothing
> happens.
>
> Can anyone share some suggestions?

Here some backgroup on a relay agent. This can/should be first configured
on a router if possible.

http://www.tech-faq.com/dhcp-relay-agent.shtml

--
Paul Bergson
MVP - Directory Services
MCTS, MCT, MCSE, MCSA, Security+, BS CSci
2008, 2003, 2000 (Early Achiever), NT4
Microsoft's Thrive IT Pro of the Month - June 2009

http://www.pbbergs.com

Please no e-mails, any questions should be posted in the NewsGroup This
posting is provided "AS IS" with no warranties, and confers no rights.

"tdnnash25" <> wrote in message
news:794325db-5212-47a3-9310-...
On Oct 29, 7:27 am, "Paul Bergson [MVP-DS]" <pbbergs@no_spammsn.com>
wrote:
> I would suspect it is either the fact the DHCP server hasn't been
> authorized
> yet in AD -or- the clients aren't on the same subnet as the DHCP server
> and
> a dhcp helper (Relay on a router) on the remote subnets hasn't been
> configured.
>

It has been authorized in AD. The clients I'm testing with are on a
different subnet in a VM. But, the primary DHCP server is on the same
subnet as the secondary DHCP server (10.10.11.x). I am not sure about
a Relay though.

> On Oct 29, 7:27*am, "Paul Bergson [MVP-DS]" <pbbergs@no_spammsn.com>
> wrote:
>> I would suspect it is either the fact the DHCP server hasn't been authorized
>> yet in AD -or- the clients aren't on the same subnet as the DHCP server and
>> a dhcp helper (Relay on a router) on the remote subnets hasn't been
>> configured.
>>
>
> It has been authorized in AD. The clients I'm testing with are on a
> different subnet in a VM. But, the primary DHCP server is on the same
> subnet as the secondary DHCP server (10.10.11.x). I am not sure about
> a Relay though.

If the clients are on a different subnet, then I assume that the DHCP
scope is set to an IP range for the subnet the clients are sitting on,
and the DHCP server is either directly connected to that subnet
(meaning the interface of the DHCP server has an IP on that subnet), or
there is a DHCP Relay agent to receive/transmit DHCP requests from that
subnet to the DHCP server on a different subnet.

DHCP will only work if one of the interfaces are configured with a
configuration with an IP address in the same subnet as the scope but
not within the scope. Otherwise, if the clients are on a subnet the
DHCP server is not connected to, then you must use some sort of DHCP
relay agent or IP helper.

Ace

--
Ace

This posting is provided "AS-IS" with no warranties or guarantees and
confers no rights.

Please reply back to the newsgroup or forum for collaboration benefit
among responding engineers, and to help others benefit from your
resolution.

Ace Fekay, MCT, MCITP EA, MCTS Windows 2008 & Exchange 2007, MCSE &
MCSA 2003/2000, MCSA Messaging 2003
Microsoft Certified Trainer

For urgent issues, please contact Microsoft PSS directly. Please check
http://support.microsoft.com for regional support phone numbers.

Do you have network teaming configured on the DHCP server? I had a similar
problem and it ended being the teaming of the nic's on the DHCP server that
was preventing the DHCP server from handing out ip's to the client machines

"Ace Fekay [MCT]" <> wrote in message
news: t.org...
>> On Oct 29, 7:27 am, "Paul Bergson [MVP-DS]" <pbbergs@no_spammsn.com>
>> wrote:
>>> I would suspect it is either the fact the DHCP server hasn't been
>>> authorized
>>> yet in AD -or- the clients aren't on the same subnet as the DHCP server
>>> and
>>> a dhcp helper (Relay on a router) on the remote subnets hasn't been
>>> configured.
>>>
>>
>> It has been authorized in AD. The clients I'm testing with are on a
>> different subnet in a VM. But, the primary DHCP server is on the same
>> subnet as the secondary DHCP server (10.10.11.x). I am not sure about
>> a Relay though.
>
> If the clients are on a different subnet, then I assume that the DHCP
> scope is set to an IP range for the subnet the clients are sitting on, and
> the DHCP server is either directly connected to that subnet (meaning the
> interface of the DHCP server has an IP on that subnet), or there is a DHCP
> Relay agent to receive/transmit DHCP requests from that subnet to the DHCP
> server on a different subnet.
>
> DHCP will only work if one of the interfaces are configured with a
> configuration with an IP address in the same subnet as the scope but not
> within the scope. Otherwise, if the clients are on a subnet the DHCP
> server is not connected to, then you must use some sort of DHCP relay
> agent or IP helper.
>
> Ace
>
> --
> Ace
>
> This posting is provided "AS-IS" with no warranties or guarantees and
> confers no rights.
>
> Please reply back to the newsgroup or forum for collaboration benefit
> among responding engineers, and to help others benefit from your
> resolution.
>
> Ace Fekay, MCT, MCITP EA, MCTS Windows 2008 & Exchange 2007, MCSE & MCSA
> 2003/2000, MCSA Messaging 2003
> Microsoft Certified Trainer
>
> For urgent issues, please contact Microsoft PSS directly. Please check
> http://support.microsoft.com for regional support phone numbers.
>
>