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Win Server 2008 R2 Network problem

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Bird222

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I am running Windows Server 2008 R2 64-bit as a guest on Win 7 using VMware workstation.
I keep getting an error saying 'there is a conflict with an IP address on the network'. The event log says 'the system detected an address conflict for IP address 0.0.0.0 with hardware address 00-1E-**-**-**-**. Network operations on this system maybe disrupted as a result' The event id is 4199. My network adapter is set to 'bridged'. This seems to work fine for XP Pro and Ubuntu. Can someone help to get my network working?

Also, Server 2008 seems to think I am trying to connect to a public network instead of a private one

Thanks!
 
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You've set the same IP address on this guest as on another machine on the network...
 
can you copy/paste your entire ipconfig /all here from the guest machine?

maybe take a screen of your vmware workstation network settings too?

I have only run R2 in a Hyper-V environment, not in VB or VMware
 
Bird222 said:
No it gets its IP from the router (DHCP).
Click to expand...

One of your other VMs has the same mac address. Use the VMware KB to find the static list, pick one from there, and then power the machine up - boom, new IP!
 
lopoetve said:
One of your other VMs has the same mac address. Use the VMware KB to find the static list, pick one from there, and then power the machine up - boom, new IP!
Click to expand...

But none of the other VM's are powered own???
 
4saken said:
can you copy/paste your entire ipconfig /all here from the guest machine?

maybe take a screen of your vmware workstation network settings too?

I have only run R2 in a Hyper-V environment, not in VB or VMware
Click to expand...

Here are the screenshots

winser2008.jpg


winser20082.jpg


I don't know if it matters but the host network card is wireless as this is on a laptop.
 
The wireless might be the problem. Some wireless cards don't support modifying the MAC address on outgoing packets.

Statically configuring the IP address should work if changing the MAC address doesn't.
 
yeah. It also may be netbios reporting the issue if one of the other vms HAD the same IP.
 
Your DHCP server is not handing that machine an IP address or it is not working / can't communicate with the server. An IP in the 169 range is what windows will set your IP to when it cannot get an IP.

Set that IP to a static address or look in to why it can't grab an IP from your DHCP server.


Do you need this machine to have internet access or are you just creating an isolated sandbox to play around with Server 2008 R2?
 
ah. Switch what adapter bridged is using, hit apply. Then switch it back, and hit apply (in the virtual network editor). Known issue.
 
Ok, it does have something to do with the wireless card. Using the wired NIC worked fine. One thing I noticed is that the network adapter on Server 2008 is 'Intel PRO/1000 MT Network Connection' and the network adapter on the Win XP SP3 (another guest) is 'VMware Accelerated AMD PCNet Adapter'. Is it possible to install this adapter on the Server 2008? The server 2008 is being assigned an IP address, but for some reason it sends a 'DHCP Decline' packet. I discovered this using wireshark.
 
No, 2k8 doesn't have an VMXNET driver. It's not the virtual network card, it's the virtual networkS themselves.

Try what I suggested - I use this tool and know it far better than you'd expect. Set the bridged adapter to something random, then set it to the one you want. It resets the adapters.
 
lopoetve said:
No, 2k8 doesn't have an VMXNET driver. It's not the virtual network card, it's the virtual networkS themselves.

Try what I suggested - I use this tool and know it far better than you'd expect. Set the bridged adapter to something random, then set it to the one you want. It resets the adapters.
Click to expand...

I tried that, it didn't work.
 
you hit ok between each setting?

Try NAT then, unless it has to have an IP on the actual network.
 
NAT seems to work. At least the network card seems connected and has an IP address. However, I can't get a webpage to load. I can ping 'www.google.com' from the command line, but the webpage won't load. I have tried with both IE and Firefox.
 
ok. Are the virtual network adapters in the network adapter list on Win7?
 
Oh, I forgot I disabled both of those sometime ago. However, I don't understand why ping would work with them disabled but the webpage won't??? I really would actually like to have the network adapter on the same subnet as the rest of the network. I wonder why Server 2008 is sending a 'DHCP Decline' packet after it has been assigned an IP by the router?
 
Bird222 said:
Oh, I forgot I disabled both of those sometime ago. However, I don't understand why ping would work with them disabled but the webpage won't??? I really would actually like to have the network adapter on the same subnet as the rest of the network. I wonder why Server 2008 is sending a 'DHCP Decline' packet after it has been assigned an IP by the router?
Click to expand...

Because the IP is already in use on the network. We've given you multiple avenues to diagnose, or workaround this issue.
 
or, at least, it thinks it is. Can you tell what addy the dhcp server is returning? It might be giving it the same IP as the host.
 
keenan said:
Because the IP is already in use on the network. We've given you multiple avenues to diagnose, or workaround this issue.
Click to expand...

That is not it. There are no other devices on the network that are using these IPs. Looking at my router, I can see all these different IPs it gives server 2008. You can just watch it hand them out and then 2008 will reject it and the cycle starts all over again.
 
Bird222 said:
That is not it. There are no other devices on the network that are using these IPs. Looking at my router, I can see all these different IPs it gives server 2008. You can just watch it hand them out and then 2008 will reject it and the cycle starts all over again.
Click to expand...

Something is responding to ARP requests for that IP address. What do your packet captures on the host show? Can you post one up here?
 
lopoetve said:
or, at least, it thinks it is. Can you tell what addy the dhcp server is returning? It might be giving it the same IP as the host.
Click to expand...

Yes, I can see the addresses in the router and on wireshark captures. They are not the same as the host. One thing I do notice (which is probably normal) in the packets is that the source of the packet is the host NIC, but deeper inside the packet (in the 'bootstrap protocol' section) the 'client MAC address' is the VMware adapter. This is probably the same behavior as the wired. I think I'll do a capture of the wired connection.
 
Bird222 said:
Yes, I can see the addresses in the router and on wireshark captures. They are not the same as the host. One thing I do notice (which is probably normal) in the packets is that the source of the packet is the host NIC, but deeper inside the packet (in the 'bootstrap protocol' section) the 'client MAC address' is the VMware adapter. This is probably the same behavior as the wired. I think I'll do a capture of the wired connection.
Click to expand...

That's strange unless VMware is acting as a DHCP relay behind your back, which is quite possible, but doesn't really make sense in bridge mode. Are you saying that for all other traffic, the addresses are correct? What happens when the guest makes an ARP request after receiving the lease offer and discovers the address in use? Where does that ARP response come from?
 
Bird222 said:
Yes, I can see the addresses in the router and on wireshark captures. They are not the same as the host. One thing I do notice (which is probably normal) in the packets is that the source of the packet is the host NIC, but deeper inside the packet (in the 'bootstrap protocol' section) the 'client MAC address' is the VMware adapter. This is probably the same behavior as the wired. I think I'll do a capture of the wired connection.
Click to expand...

I just checked. Wired shows the Vmware MAC not the host MAC. So it is different than the wireless. I also did a packet capture of Win XP Pro on the wireless (which works) and it shows the host MAC as the source but has the VMware MAC deeper in the packet just like 2008 R2. The only difference I can see in the packet captures are these (XP wireless vs. R2 wireless):

XP does a 'DHCP Request' and in that request it asks for a specific IP address. Then my router sends back a 'DHCP ACK' that grants the IP address and has the VMware MAC in the packet.

2008 R2 does a 'DHCP Discover' packet. Then the router sends a 'DHCP OFFER' packet that has the IP address that the router wants to assign and also has the VMware MAC deeper in the packet. Then almost simultaneously (about a thousandth of a second later), R2 sends out a 'DHCP Request' packet requesting the same IP address that was in the router's 'DHCP Offer' packet. Finally, the router sends a 'DHCP ACK' packet that has the same IP address. R2 will keep this IP address for about 5 or 6 hundredths of a second (it sends out a 2-3 packets), then it will send the 'DHCP Decline' packet.
 
Bird222 said:
I just checked. Wired shows the Vmware MAC not the host MAC. So it is different than the wireless. I also did a packet capture of Win XP Pro on the wireless (which works) and it shows the host MAC as the source but has the VMware MAC deeper in the packet just like 2008 R2. The only difference I can see in the packet captures are these (XP wireless vs. R2 wireless):

XP does a 'DHCP Request' and in that request it asks for a specific IP address. Then my router sends back a 'DHCP ACK' that grants the IP address and has the VMware MAC in the packet.

2008 R2 does a 'DHCP Discover' packet. Then the router sends a 'DHCP OFFER' packet that has the IP address that the router wants to assign and also has the VMware MAC deeper in the packet. Then almost simultaneously (about a thousandth of a second later), R2 sends out a 'DHCP Request' packet requesting the same IP address that was in the router's 'DHCP Offer' packet. Finally, the router sends a 'DHCP ACK' packet that has the same IP address. R2 will keep this IP address for about 5 or 6 hundredths of a second (it sends out a 2-3 packets), then it will send the 'DHCP Decline' packet.
Click to expand...

This is all sounds perfectly normal except for the DHCP Decline. Take packet captures on the guest and host simultaneously, post the .cap files and I'll take a look. I do think your wireless card is not allowing the source mac rewriting, but the symptoms are rather strange for that to be the cause.

R2 will keep this IP address for about 5 or 6 hundredths of a second (it sends out a 2-3 packets), then it will send the 'DHCP Decline' packet.
Click to expand...
Something happens in this time that's making Windows think the IP is already taken. What you omitted (what it sends out and receives during that time) is what's interesting.
 
Doing a quick search on google, it appears that the DHCP Discover packet is used to determine if there is another DHCP server on the network. If there is then R2 stops the DHCP service, but the funny thing is is that R2 isn't running DHCP server, it hasn't been setup yet. Are you saying you want me to install wireshark on the guest computer and run it?
 
Well this issue started with Win Server 2008. I tried it on Win Server 2003 R2 and it worked fine. Not surprisingly the DHCP request worked just like Win XP.
 
Bird222 said:
Doing a quick search on google, it appears that the DHCP Discover packet is used to determine if there is another DHCP server on the network. If there is then R2 stops the DHCP service, but the funny thing is is that R2 isn't running DHCP server, it hasn't been setup yet. Are you saying you want me to install wireshark on the guest computer and run it?
Click to expand...

The discover message is used to find available servers before making a request for configuration. It's the first stage of a DHCP negotiation. Your XP and 2003 boxes aren't using it because they have stored a previous lease and will attempt to regain that lease before obtaining a fresh one. If regaining that lease were rejected you'd see the same behaviour as your 2008 box is exhibiting: apparently a completely normal DHCP session.

You keep running around my suggestions and trying to find other things to pursue that aren't part of the problem. If you are absolutely 100% certain that the address your router gives out in the lease is not already in use, then either some device on the network is responding to this IP when it shouldn't be or something wonkier is happening inside VMware. If you just posted packet captures I'm fairly sure that this should be pretty easy to track down. Even easier if you have captures from both the host (preferably router, but that's probably not an option) and guest. You're making things difficult.

The crux of this is going to be figuring out why the 2008 VM thinks its IP is already in use if it actually is not. It's seeing some traffic coming from *somewhere* that makes it think this, though the reason that's happening is probably something else, it will give insight.
 
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well, fwiw, Win7 and server 2k8 are not yet supported technically in workstation. It may be that the guest is seeing some portion of the host traffic there...
 
Please know that I in no way mean any disrespect when I say this, but I am not trying to avoid your suggestions. In fact, I asked in the previous message if you wanted me try to run wireshark on the guest? As far as your comment about the 2003 box, I don't see how that is possible as I just installed it in VMware to test the theory so there shouldn't be any previous stored lease. I'll try to post the packet captures.
 
I've seen weird things like that happen with netbios - make sure the 2k3 box and the 2k8 didn't get assigned the same MAC addy (edit the vmx file, it'll show you what the generated MAC is). :)
 
No they didn't have the same MAC. It doesn't appear that you can have attachments on posts, so if you want to PM me your email address I can send you the files.
 
Bird222 said:
As far as your comment about the 2003 box, I don't see how that is possible as I just installed it in VMware to test the theory so there shouldn't be any previous stored lease. I'll try to post the packet captures.
Click to expand...

It probably secured itself a lease during the install or something, depends how you installed it and when you did the capture. If it wasn't the very first ever DHCP session (which IIRC happens before the first reboot during the install process), it'll try to regain its previous lease.

You can e-mail me at error401 [at] fastmail.fm
 
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