https://lwn.net/Articles/531114/
https://web.mit.edu/rhel-doc/4/RH-DOCS/rhel-rg-en-4/
https://web.mit.edu/rhel-doc/4/RH-DOCS/rhel-rg-en-4/ch-iptables.html
https://man7.org/linux/man-pages/man2/clone.2.html
https://man7.org/linux/man-pages/man2/setns.2.html
https://curl.se/