Title: CentOS closes the firewall

CentOS 633601) takes effect permanently and will not be restored after restarting. Opening and closing : chkconfig iptables takes effect immediately. After restart, resume : service iptables start to close : service iptables stop centos 7: system ctl start firewall d.service# start firewall system ctl stop firewall d.service# stop firewall system CTL disable firewall d.service # It is forbidden to start the firewall to query the transmission control protocol connection : netstat-n | awk'/TCP/{s [$ nf]} end {for (a in s) print a, S[a]}' query port.