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klstay
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2nd NIC in Virtual Machines

I have several virtual machines each with a 2nd NIC they need to use to communicate among themselves privately. The primary NIC on each are in separate and isolated VLANs and are working just fine. The 2nd NIC in each can communicate with physical hosts on that VLAN, but none of these virtual machines can communicate with each other.

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golddiggie
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If you're looking to have a bubble network for just the VM's to communicate over it's really rather simple... Create a new vSwitch but don't attach a pNIC to it... Have it make a VM port group on it, name it something obvious, and add that connection to the VM's that need to intercommunicate... If you create the new NIC's, connected to the new vSwitch, with the VMXNET3 option, then you have the potential of seeing 10Gbps communication between the VM's (depending on the VM OS and such)... I would also not use VLAN when you build the new vSwitch...

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klstay
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Tried it - no joy.

All I get from any VM trying to reach another is "destination host unreachable."

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golddiggie
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How do you have the NIC's, inside the VM's, configured?? How are you trying to connect them to each other? If you use all fixed IP information, with a completely different IP range than your physical environment, you should be able to get it to work... Think of it just like you would a physical switch connecting x physical servers to each other... Same principles apply... The isolated vSwitch is just the path that will be used, you still need to build the isolated infrastructure to get them to talk...

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klstay
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IP addressing is all fixed. Address ranges are all completely separate.

On the first VM NIC 1 is on isolated VLAN 1 and communicates fine there. On the second VM NIC 1 is on isolated VLAN 2 and communicates fine there.

If I connect NIC 2 on both machines to isolated VLAN 3 they can communicate with other physical hosts on VLAN 3, but not each other.

If I connect NIC 2 on both machines to a vswitch which has no physical host NICs again they cannot communicate with each other. Addresses of NIC 2 are:

10.10.110.84/23

10.10.110.82/23

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