FreeBSD networking and container stacks, such as Jails, have matured and offer many useful features. However, these features are not well advertised or documented by the FreeBSD project. In contrast, when Solaris was still under Sun, networking capabilities and virtual switches were heavily promoted. FreeBSD has technologies like Netgraph and lightweight containers, but they are not widely publicized. Even the VNET Jails, which are widely used, are not documented in the FreeBSD Handbook. To make VNET Jails networking more accessible, this guide provides step-by-step instructions for setting up a classic Jail and configuring network connectivity. For VNET Jails, using the if_bridge interface is recommended.
https://vermaden.wordpress.com/2023/06/28/freebsd-jails-containers/