centos7防火墙拒绝出站流量

firewall-cmd --direct --add-rule ipv4 filter OUTPUT 0 -m state --state ESTABLISHED,RELATED -j ACCEPT 

firewall-cmd --direct --add-rule ipv4 filter OUTPUT 2 -j DROP

firewall-cmd --reload

#查看规则
firewall-cmd --direct --get-all-rules

参考资料
https://serverfault.com/questions/618164/block-outgoing-connections-on-rhel7-centos7-with-firewalld

https://unix.stackexchange.com/questions/755756/using-zones-in-firewalld-to-block-outbound-access

https://superuser.com/questions/1391650/how-can-i-configure-firewalld-to-block-all-outgoing-traffic-except-for-specific