Please provide a short (approximately 100 word) summary of the following web Content, written in the voice of the original author. If there is anything controversial please highlight the controversy. If there is something surprising, unique, or clever, please highlight that as well. Content: Title: Jails on FreeBSD Site: Jails on FreeBSD We have had Jails on FreeBSD since 4.0 came out 19 years ago in March 2000. This describes how to setup jails on FreeBSD 12 without any helpers. Steps I usually place all jails under /var/jail and give each jail its own directory, which reflects its short hostname. For this, I use bsdinstall : # bsdinstall jail /var/jail/mysql Deselect all optional system components during the installation as well as any services. On the host system, you can either create one big /etc/jail.conf or one /etc/jail.HOSTNAME.conf per jail, e.g. /etc/jail.mysql.conf : exec.start = "/bin/sh /etc/rc"; exec.stop = "/bin/sh /etc/rc.shutdown"; exec.clean; mount.devfs; path = "/var/jail/mysql"; mysql { host.hostname = ""; ip4.addr = "lo1|"; } In order to have the jails started and stopped during system boot and shutdown, respectively, add this to /etc/rc.conf : jail_enable="YES" jail_list="mysql" Unless you want to assign each jail an IP address from your network, you have to setup a host-only network. In /etc/rc.conf : cloned_interfaces="lo1" ifconfig_lo1="inet netmask" Usually, you want to give your jails Internet access. Thus, we need NAT on the host. First, create /etc/ipfw.rules : nat 1 config if vtnet0 same_ports add nat 1 ip from any to any via vtnet0 add allow ip from any to any Replace vtnet0 by your actual network interface. Now add this to /etc/rc.conf in order to activate IP forwarding and to have the firewall rules loaded during system boot: kld_list="ipfw_nat" gateway_enable="YES" firewall_enable="YES" firewall_type="/etc/ipfw.rules" Reboot the host. Afterwards, you can log into your jails, e.g. by typing # jexec mysql /bin/csh Optionally, set up a local unbound as caching DNS resolver: # cat >/etc/unbound/conf.d/local.conf <