I have a MaaS server, it has two network interfaces. One external eth0, and one for the internal network eth1(Nodes network). eth1 is where the DNS and dhcp server managed interface. I want a mix of physical servers, and one KVM VM run on the MaaS server. I manage to create VM's to PXE Boot, and created a bridge br01 bridged with the eth1 interface.

auto br0
iface br0 inet dhcp
        bridge_ports eth1
        bridge_stp off
        bridge_fd 0
        bridge_maxwait 0

And that bridge is associated with the VM's network.

Now this works if created on an external server connected to the eth1 network(tried earlier as proof of concept).

But what I want is to move this KVM setup over to the MaaS Server itself(to free up a physical server as Node), and then this network configuration is not working.

The network part of the VM's xml file:

<interface type='bridge'>
      <mac address='52:54:00:3c:a5:18'/>
      <source bridge='br0'/>
      <model type='virtio'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x03' function='0x0'/>

I created the VM using:

sudo virt-install --name=bootstrap-juju --ram=2048 --vcpus=1 
--disk path=/var/kvm/images/bootstrap-juju.qcow2,bus=virtio,size=20 
--pxe --graphics=vnc --hvm --network bridge=br0,model=virtio 

It seems that there is a problem with the bridge, when I sudo ifup br0 I get:

DHCPDISCOVER on br0 to port 67 interval 3 (xid=0xcb27ff35)
No DHCPOFFERS received.

So it seems the bridge is not getting DHCP address from the internal dhcp server.

Does anyone have any pointers here?

  • Please post the interface section of your xml definition file, /etc/libvirt/qemu/server_name.xml. The interface should be defined as type=bridge and be set to using br0 as the source bridge. see also here and here. – Doug Smythies Jan 9 '16 at 16:26
  • Updated my question with more info. Thanks for reply. – ladrua Jan 9 '16 at 20:58
  • Yes, I saw, but everything looks O.K. so I am stumped. The only other things I can think to look at are the guest /etc/network.interfaces file and the output from ifconfig on the guest. – Doug Smythies Jan 9 '16 at 22:55
  • I meant to write /etc/network/interfaces yesterday. Perhaps post both files for both the host and the guest. your sudo ifup br0 command was done on the host right? On my host I get ifup: interface br0 already configured – Doug Smythies Jan 11 '16 at 15:31

Ok, I had a few problems. My eth1 was still defined as static in my /etc/network/interfaces. I had to remove it, and change my br0 with matching static settings. Then on the Cluster master in MaaS, change the Managed DHCP-DNS interface from eth1 to br0.

Hope this helps someone.

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