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I have a KVM Guest with an adapter that is attached to a bridge interface, which has a physical nic. The physical nic's network has DHCP in the 192.168.1.0/24 range.

My guest does not get a DHCP address, and statically assigning the IP results in no layer2 connectivity.

My guest did get a 192.168.2.0/24 network, but I think that came because of KVM. I do not want the host participating in the networking, aside from passing layer 2 between the physical adapter, and the guest(s), using the bridge.

My Setup:

[root@host ~]# brctl show
br.4094     8000.406231001c29   yes     enp0s20u8
                                        enp1s0.4094
                                        vnet0

[root@host ~]# ip link list
~
4: enp0s20u8: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast master br.4094 state UP mode DEFAULT group default qlen 1000
    link/ether a2:72:9f:e6:43:96 brd ff:ff:ff:ff:ff:ff
~
6: br.4094: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP mode DEFAULT group default qlen 1000
    link/ether 40:62:31:00:1c:29 brd ff:ff:ff:ff:ff:ff
~
40: vnet0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast master br.4094 state UNKNOWN mode DEFAULT group default qlen 1000
    link/ether fe:54:00:3f:95:26 brd ff:ff:ff:ff:ff:ff

[root@host ~]# ip addr list
~
4: enp0s20u8: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast master br.4094 state UP group default qlen 1000
    link/ether a2:72:9f:e6:43:96 brd ff:ff:ff:ff:ff:ff
~
6: br.4094: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
    link/ether 40:62:31:00:1c:29 brd ff:ff:ff:ff:ff:ff
    inet 192.168.1.155/24 brd 192.168.1.255 scope global dynamic br.4094
       valid_lft 55343sec preferred_lft 55343sec
    inet6 2600:380:772e:af16:4262:31ff:fe00:1c29/64 scope global mngtmpaddr dynamic 
       valid_lft 85896sec preferred_lft 13896sec
    inet6 fe80::4262:31ff:fe00:1c29/64 scope link 
       valid_lft forever preferred_lft forever
~
13: enp1s0.4094@enp1s0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue master br.4094 state UP group default qlen 1000
    link/ether 40:62:31:00:1c:29 brd ff:ff:ff:ff:ff:ff
    inet6 fe80::4262:31ff:fe00:1c29/64 scope link 
    valid_lft forever preferred_lft forever
~
40: vnet0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast master br.4094 state UNKNOWN group default qlen 1000
link/ether fe:54:00:3f:95:26 brd ff:ff:ff:ff:ff:ff
inet6 fe80::fc54:ff:fe3f:9526/64 scope link 
   valid_lft forever preferred_lft forever

The snippet of my config for the VM:

<interface type='bridge'>
  <mac address='52:54:00:3f:95:26'/>
  <source bridge='br.4094'/>
  <model type='virtio'/>
  <address type='pci' domain='0x0000' bus='0x00' slot='0x03' function='0x0'/>
</interface>

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