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cebrooks03

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2 Vurtial Servers on same host can't ping each other

The host system is w2k3 r2 x64. Vurtial Server 2005 is installed and I have 3 guests installed. All guests are w2k3r2 x86. Firewalls are off, each VS has it's own v-nic assigned with a static ip. All ip's are on the same subnet. All guests and the host can reach the internet. Problem is that non of the guests can reach each other. Any ideas? Need more info?
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martin_babarik
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This problem is very rare but I experienced it once too. The problem is (don't know how it happened) that both of the NICs on VPCs had identical MAC address. Please use ipconfig /all on both of the machines to verify if this is the problem.
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cebrooks03

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Well I checked and they all have different macs. However, one of the servers is an application host with 3 ips assigned to the same v-nic. They all share the same mac but I believe that is as it should be.......
You're right, no problem having multiple IP's linked to one MAC. In this case I'm sorry, no better idea what to do. If you are pretty sure you disabled firewall...btw you told us "all firewalls are disabled"...do you mean FW on the guest machines? If so, try also disabling firewall on the HOST machine!
Hi there,

There is no need to turn off the firewall on the host machine.

Make sure that the virtual NIC you created is properly configured and assigned to all 3 guests. When you say they cannot reach each other, do you refer to ping or perhaps opening shared directories, etc? This is a rather straight forward setup, should work "out of the box".

Sounds like either a misconfiguration with the virtual NIC or the software firewall inside the guest OSs is blocking ICMP.
mmilic: I'd dare to kindly disagree with you. In some cases the firewall micht be blocking the traffic between virtual machines even when they are configured for "local" networking.
I've seen it many times, is I had better memory I could name those FW or AV products that do it, but I can't remember which of them work like that. Maybe NOD, Avast or McAffee, I guess some if them, but it's not important. What is important is, that it's possible (have no idea how).
Dear Martin,

I have not had this experience, however I did assume it was a case of pre-installed Windows firewall (considering OP didn't specify which firewall this was) - for which I am certain is not the cause of the problem (unless it is blocking ICMP).
There are no software firewalls enabled on this box.........
In that case, the only thing I see is a potential misconfiguration between the Guest OSs.

I would suggest that you create a new virtual NIC, two new VMs with w2k3 image on them, ensure Windows Firewall is disabled inside the Guest OSs and attempt to connect to each other. Unless you make a mistake in configuration, this scenario works fine.
Mmilic: yes in case of Windows Firewall you would be absolutelly right, as it's not blocking outgoing traffic.
Anyway thank you for specifying. I am not able to think some another idea what might be causing the problem if it's not duplicated MAC, traffic blocked by FW or AV...just one more think - isn't there some service neccessary to be running on the host computer to enable the guest computers communicate to each other? Just an idea - I'm thinking about this possible service not being started or malfunctioning.
never thought of that. I will have to look into it.........I will report back...
Do you have more than one NIC installed on the local computer?  If so,I would also check to make sure the interfaces are assigned correctly.  With VPC you can set on NIC to local or the physical NIC installed on the computer.  I would verify they are all set correctly.  


If i can think of anything else I will you know.  It seems like everyone mentioned almost everything I could think of.
ok, I have re-checked everything on the host in regards to the vNICS and vServers and the host. Everything is all on the subnet, there are no dup ip's or names. I have checked the DNS servers, yea, I know they have nothing to do with ip's but I wanted to check anyway. I can not find anything wrong with the settings. I've been all over google and I hit on something that says there is a bug in v-server 2005 SP1 and that it would be fixed in SP2. I can not find anything else repeating this. Have ya'll seen anything like this?
Sorry nsx106052, there is only 1 single NIC on the host.
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mmilic

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mmlic,

I would tend to agree with you. I'm going to go over it again and maybe post some screen shots..... If I can do that. The thing about creating more VM's is that I can't remove the ones I have. I've been using them for a long time and I have services/software that are mission critical.

Could you suggest some resources for configuring VM's, I have my own but another source might help.....
Hi,

If you remove the VM from the Administrator Website, you will certainly not remove the VHD itself - so your VM will stay intact. You can just keep it turned off during this testing in order to save up on resources. If turning them off is not possible either and you are out of resources, I'm afraid there's not much you could do.

I am not sure what these are for, but even if you do a 256 MB RAM per VM and install a windows 2003 server on it, it will work (just a bare installation with no other software installed afterwards).
ok, as per Microsoft, this is a big and will be fixed in SP2..... Thanks for the help.
Well mmilic, it was a config issue. Not sure how many times I read the docs and really I don't think it is very clear but here is what the issue was.

I had configured a vnic for each vserver and bound it to the host nic, this gets you access to the host and the rest of the lan/internet but it does not get you access to the other vserver on the same host. You need to create a second vnetwork and do not bind it to the host nic. I put this on a different subnet with static ip's but dhcp will also work.

In any case this will allow full network access including the other vservers on the same host.

art vurturial environments great!
and by the way, thanks for the push.......Chris