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I have the following configured on my ubuntu host:

virsh config for "passthrough"

  <forward mode='nat'/>
  <bridge name='ptbr0' stp='on' delay='0' />
  <ip address='' netmask=''>
      <range start='' end='' />

and my /etc/network/interfaces

auto lo 
iface lo inet loopback

auto eth0
iface eth0 inet static
dns-search blackport.local
auto eth1
iface eth1 inet manual 
auto ptbr0
iface ptbr0 inet static
    bridge_ports eth1
    bridge_fd 9
    bridge_hello 2
    bridge_maxage 12
    bridge_stp off

So in other words, I have a network, a network, and the ubuntu host has a card dedicated to each network. I want the guest vm's to hang out in 10.20.0 and be reachable from the 10.22.4 netowrk. My ptbr0 card comes up with the ipaddress which IS reachable from the 10.22.4 network. However, when my first kvm comes up with the address, it is not reachable, with a "Destination port unreachable"

I tried to set up a route on the ubuntu host that pushed traffic to the ptbr0 device, but it did not work. What else can I try to make this happen?


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