FWIW this can also be done with ipsets. [1] ipset hash tables are quite useful if you are blocking a large number of hosts. The CPU load is much lower than hav

FWIW this can also be done with ipsets. [1] ipset hash tables are quite useful if you are blocking a large number of hosts. The CPU load is much lower than having individual rules for each host blocked. You can set any time limit on a ipset or have no time limit. You can also dynamically insert ip's into ipsets using iptables rules. [1] - https://superuser.com/questions/1412286/time-limited-whitelisting-of-ip-addresses-with-ipset-and-iptables https://superuser.com/questions/1412286/time-limited-whiteli...