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On a CentOS server, ifconfig shows several vnetX interfaces (vent1, vent2, vent100), how can I add some more?

(I'd like to add a couple of virtual machines, so I need to add some more virtual interfaces that I can assign to the virtual machines).

Also, from what I understand, these vnetX interface are internal, between the host and virtual guest, is this correct?

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up vote 1 down vote accepted

these are set up on the VM level, you assign NICs to a VM, and it starts with them, creating vnetX NICs in the process.

As for how the networking is set up, just search for "libvirt bridge" and "libvirt NAT"

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Why not use bridge mode in KVM for the Guest machines.

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Because that's how this VM host is already set up, so I'd like to add to it in the same way it has been set up. – jwbensley Mar 9 '12 at 17:32

I think he is probably using bridge mode, check this typing brctl show. If there is one bridge, you can add extra interfaces using tunctl tool.

Like this: tunctl -u root -t interfaceNameX

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