On Thu, May 7, 2020 at 12:12 AM Sam Varshavchik <mrsam@xxxxxxxxxxxxxxx> wrote: > Is there a way with firewall-cmd to /really/ block an IP address, new or > established connections, or is manually adding an iptables rule my only > option? You can bypass connection tracking for dropping existing connections by adding a rule in the *raw* or *mangle* table when using the iptables backend. The fastest way I know of, is to add a direct rule: If 1.2.3.4 is the offending IP, something like: firewall-cmd --permanent --direct --add-rule ipv4 raw PREROUTING 0 -s 1.2.3.4 -j DROP firewall-cmd --reload should work fine. After that iptables -n -t raw -L should list the IP with the DROP target, REJECT doesn't work here. A more efficient way would be to use ipsets: firewall-cmd --permanent --zone=drop --add-source=ipset:blacklist firewall-cmd --permanent --ipset=blacklist --add-entry=1.2.3.4 firewall-cmd --permanent --ipset=blacklist --add-entry=4.3.2.1 This should terminate any existing connection and prevent new ones. _______________________________________________ users mailing list -- users@xxxxxxxxxxxxxxxxxxxxxxx To unsubscribe send an email to users-leave@xxxxxxxxxxxxxxxxxxxxxxx Fedora Code of Conduct: https://docs.fedoraproject.org/en-US/project/code-of-conduct/ List Guidelines: https://fedoraproject.org/wiki/Mailing_list_guidelines List Archives: https://lists.fedoraproject.org/archives/list/users@xxxxxxxxxxxxxxxxxxxxxxx