iptables -F iptables -X iptables -Z /usr/sbin/iptables-sav的意思

iptables -F: This command flushes all the existing rules from the iptables chains. It deletes all the rules, thus giving a clean state to the firewall.

iptables -X: This command deletes all the user-defined chains created in the iptables.

iptables -Z: This command resets the packet and byte counters for all the chains in the iptables.

/usr/sbin/iptables-save: This command saves all the existing rules in the iptables to a file, which can be used later to restore the firewall settings.