KVM VM problems

uberwebguru

I am faced with couple questions with my lab laptop

1. Why is that the host system doesn't have an ipv4 address when system is connected through wifi? The other VMs do have ipv4 except the host system


2. Why is it that the VMs cannot communicate to each other like ssh and so on?

3. I am trying to test the VNC remote access from VM to VM...how do i do this?


Thanks.

onesaint

Hi uberwbguru,

All those questions require background information in order to figure out how things are configured and why they aren't working like they should. With that,

1a. for your host, what OS are you running? Can you paste the output from an ifconfig? Are there other devices getting an IP from your AP? Have you configured the wifi interface correctly?
1b. KVM is creating network interfaces for the VMs.

2. VM network interfaces are NATed by default. So, the VMs are NATed (in different subnets) to either your physical wifi nic or to eth0. In either case, outbound traffic from the VM will have no knowledge of other NATed networks, unless you add routes for the VM subnets, e.g.:

Physical nic: 192.168.0.2/24
VM1: 192.168.1.2/24
VM2: 192.168.2.2/24

there is no route from 192.168.1.x to 192.168.2.X. Add one with route or to IPtables. see here: Networking - KVM and here: http://wiki.libvirt.org/page/Networking

3. With the info from q.2 you should then be able to connect VNC provided you've got those ports allowed in IPtables and that traffic is routed to the VMs correctly. You might want to start by VNCing from hypervisor to VM, then VM to VM.

Good luck!