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I have a virutal environment as follows:

  • a Windows server 2008 with two NIC's. One NIC is connected to internel 'LAN' and the other to 'LAN2'. Roles: DHCP, AD, DNS and RRAS.
  • a Windows 7 client. The NIC is connected to 'LAN2'.

Almost everything is out of the box, I only set up two DHCP pools.

The problem is that the client can't obtain a IP of the DHCP server. The server also can't be pinged with a static ip.. (the connections details shows incomming packets)

But when I change the network of the client to "LAN", then I get a IP from the DHCP without problems.

How does this come?

share|improve this question
What pools do you have configured on your DHCP server? – Lewis Aug 3 '11 at 15:09
Pool 1: /24, Pool 2: /24 – Sven van Zoelen Aug 3 '11 at 23:25
And the Bindings are OK? DHCP is listening on both NICs? netstat -an – Lewis Aug 4 '11 at 6:43
A lot of data is flying through the console. For what kind of data must I look for? – Sven van Zoelen Aug 5 '11 at 10:27
You're looking to see if the DHCP service is listening on all IP addresses bound to the server. DHCP listens on UDP 67 so perhaps a better command to run would be netstat -an -p UDP and look for an entry listing port 67 next to it. Better still, provide us with the entire list. – Lewis Aug 5 '11 at 13:48

DHCP requests are ICMP broadcasts. And broadcasts are not routed to WAN by design. I could have lookup the RFC, but it is a fact.

ICMP broadcasts are only valid in local LAN and so it can only work inside the LAN.

share|improve this answer
I only named the virtual network "WAN". I could name it whatever i wanted. So it can be handled as a LAN. – Sven van Zoelen Aug 3 '11 at 12:22
So what are your IPs and netmasks on each of the server's NIC? – mailq Aug 3 '11 at 12:26
LAN: /24 and on LAN2: /24 – Sven van Zoelen Aug 3 '11 at 12:32
Looks OK. Then there is either a firewall on NIC2 that blocks ICMP from LAN2 or the virtual network card on NIC2 is not configured correctly. I would try to reach other destinations from the server via LAn2. – mailq Aug 3 '11 at 12:42
But everything is default. I installed server 2008, installed the server roles. Configured dhcp, rras and ad. And that's it. It's a virtual environment, so how can it be configured wrong? I disabled the firewall, but still no go. – Sven van Zoelen Aug 3 '11 at 13:41

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