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Hyper-V guest machine cannot connect to anything other than the host and another hyper-v server on the same host. Cannot contact gateway
I have 2 hyper V guests on the same host. They are both configured the same in regards to the network cards and both have the same gateway and DNS servers. They are on the same domain, the one that is functioning properly is a domain controller. I have tried removing and reinstalling the NIC on the machine acting up but am not able to get any change in connectivity, I can only contact the host and its contents. I am using Server Standard 2012 R2 for both the host and guest OS's. Any ideas on what I should do other than do a full reload on machine acting up?
ASKER
There is only one switch configured, both hyper-v guests are on that switch and it is an external switch. I double checked the subnet mask and thank god that was not off or that would have been embarassing. ipconfig attached
Next steps would be nslookup tests. Traceroute tests. Ping tests. See where things are choking up.
ASKER
Right, I ping tested earlier and I can ping the host, I can ping the other hyper-v guest, but I cannot ping the gateway or anything outside of the NIC on the host.
Had not tried a tracert, that just comes back with a destination host unreachable.
nslookup is able to bring back results for anything I try because the other guest on the hyper-v host is a domain controller so it is pulling info from that DNS
Had not tried a tracert, that just comes back with a destination host unreachable.
nslookup is able to bring back results for anything I try because the other guest on the hyper-v host is a domain controller so it is pulling info from that DNS
Is there another machine on the local network that does respond to ping from the host and the working VM *and* fails to respond to the dysfunctional VM? Both facets are important. After all, a software firewall can block pings, and then it wouldn't respond to working VMs either, so isolating the differences in behavior is important.
ASKER
Yep, I can ping another domain controller on the network from both the host and functional vm. The dysfunctional vm cannot ping it.
ASKER
BTW the firewall on all of these machines is off.
Very strange. I don't have any easy suggestions I can make at this point.
ASKER
Also, as of right now, because of port space issues, there is only 1 NIC plugged in currently.
That being said, when we remove the virtual switch and create a new one it marries up with the first guest machine that connects to it and allows network access. The second machine that is cut on has these issues where it can't contact the default gateway and acts like it is part of the internal network only. I will be plugging in the second NIC tomorrow to see if that helps...do you think the fact these 2 guests and the host are on the same NIC is causing my issue?
That being said, when we remove the virtual switch and create a new one it marries up with the first guest machine that connects to it and allows network access. The second machine that is cut on has these issues where it can't contact the default gateway and acts like it is part of the internal network only. I will be plugging in the second NIC tomorrow to see if that helps...do you think the fact these 2 guests and the host are on the same NIC is causing my issue?
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ASKER
Come to find out the switch that this is plugged into has a port-security set at 3 so I am exceeding that maximum since there is a dummy switch between them funneling them into 1 port. Thanks for the suggestions and help guys. Handing out points for the good suggestions and walkthrough
The other low-hanging fruit possibility is a misconfigured subnet mask, which isn't unique to Hyper-V. Basic networking...to use a gateway, the server has to properly know what traffic is local and what traffic needs to be routed. An ipconfig would be helpful.