I agree with TheBiggestSmallOne. Warden was/is my choice of chroot (jail) util. Tho, I don’t care if it has GUI. I actually prefer to deal with Warden in CLI.
Why? because it is simple, handy enough for creating quick FreeBSD world to test things and ez enough to manage and deal with it. And lastly, I can read and understand Warden’s scripts.
I don’t want to dig into man pages that read like PhD theses, just to find the most important set of commands and switches to control any *NIX based utility.
I tried too many so called OS level/VBS (VBS=Virtual BullShit) schemes on various OS platforms, that made my head spin.
In FreeBSD/TrueOS – chroot, raw jails, iocage, ezjails, Docker
In Linux: chroot, LXC, Docker
In MSO$: Docker, Hyper-V, Containers
None of the above provided me with a simple solution, like Warden, that I needed for testing of my TCP/IP services to the outside world, such as: httpd, smtpd, sshd and and few others.