# jail addr created on host and patch to jail. jail canNOT add, modify or delete addresse

@SaTurn-> sudo jexec foo
root@foo:/ # ifconfig
vtnet0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> metric 0 mtu 1500
lo0: flags=8049<UP,LOOPBACK,RUNNING,MULTICAST> metric 0 mtu 16384
root@foo:/ #  #note: inside jail foo

# /etc/jail.conf
foo{
 ip4.addr = "vtnet0|10.10.0.1/32";
}

@SaTurn-> sudo service jail stop foo
Stopping jails: foo.
@SaTurn-> s vi /etc/jail.conf
@SaTurn-> sudo service jail start foo

root@foo:/ # ifconfig
vtnet0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> metric 0 mtu 1500
        inet 10.10.0.1 netmask 0xffffffff broadcast 10.10.0.1