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Host is Windows 7 Guest is Ubuntu 11.04

Network adapter is wireless

I can ping other computers on the network but not the host. No firewall are involved.

Sniffing the traffic with wireshark it looks like both the host and the guest are using the same MAC address. My guest simply doesn't receive a reply when asking for (the host) My router has no problem giving both of them different IP addresses but maybe duplicate MAC address is the problem?

It seems logical that both will have the same MAC address (from the host point of view) but it strange that there is no work around for this because otherwise I don't see how the host and guess are supposed to communicate.

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downloading a VM appliance, I'll try and replicate this shortly. – SpacemanSpiff Jun 2 '11 at 3:03
What is the IP of the guest? – KCotreau Jun 2 '11 at 3:08
What are you using for virtual machine? (VirtualBOX?) yes it would be an issue if both machines have the same MAC. – Branden Jun 2 '11 at 6:29
Welcome to Server Fault! I have removed your VMware tag as VMware is a company. Please consider adding a product specific tag which can be found as vmware-product. – Iain Jun 2 '11 at 21:29
To clarify Iain's comment, tag this with vmware-player, vmware-workstation, or vmware-server since they are all product from VMware, and your answer may depend on which one you are using. – Jed Daniels Jun 2 '11 at 23:07
up vote 2 down vote accepted

If wireshark is really showing the same MAC address, then you probably aren't actually using bridged networking, but are instead using NAT (and this makes sense since you can ping out from the Ubuntu machine to other machines on your network). But, assuming you are in fact using Bridged networking:

To start, I'd suggest some basic troubleshooting to see if there are really no firewalls involved (both Windows and Ubuntu have them on by default, IIRC). From Ubuntu, attempt to ping your windows IP, then immediately do arp -an to see if there is a mac address associated with the corresponding IP. Then do the same from windows, although the arp command to use is just arp -a. If you have arp entries, then things are probably working, but a firewall is probably blocking your packets in windows or Ubuntu (you can double check that the MAC addresses in arp match those that the systems think they have by checking ifconfig in Ubuntu and ipconfig -all in Windows).

[Edit to answer question in comment]: VMware assigns the virtual machine a unique mac address, which when in bridged mode, is what is seen on the wire. ifconfig in Ubuntu should show you the mac that VMware has assigned (it will probably be 00:50:56:something or 00:0C:29:something).

Can you paste the output of ipconfig /all and ifconfig -a from Windows and Ubuntu respectively?

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the arp command shows <incomplete> from the guest to the host and shows a MAC address when trying host to guest (ping works in this case) which is more less what the results that you would expect given the problem I am having. A question about bridged networking: since both and guest are using the same physical adapter how is the duplicate MAC address problem supposed to be solved? – user199421 Jun 3 '11 at 15:19
It shouldn't. I think that MAC duplicity should stay the same.… – Henry Aloni Nov 16 '12 at 13:14

Please turn your guest firewall off and it will be solved.

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