I tested various combinations, but the simplest is:
```
host# ngctl mkpeer . eiface test ether
host# ngctl mkpeer ngeth0: bridge ether link99
host# ngctl name ngeth0:ether vmbridge
host# ifconfig ngeth0 192.168.1.1/24 up
host# sh vmrun.sh -c 4 -m 1024M -t netgraph/socket=vm0/relpath=vmbridge:/hook=vm0link/peerhook=link0 -d freebsd-0.img freebsd-0
host# sh vmrun.sh -c 4 -m 1024M -t netgraph/socket=vm1/relpath=vmbridge:/hook=vm1link/peerhook=link1 -d freebsd-1.img freebsd-1
root@fbsd0:~ # ifconfig vtnet0 192.168.1.2/24 up
root@fbsd1:~ # ifconfig vtnet0 192.168.1.3/24 up
```
Test ping, iperf3 between 192.168.1.1, 192.168.1.2, 192.168.1.3