在 CentOS 7
暫時開放 ftp 服務
#firewall-cmd --add-service=ftp

永久開放 ftp 服務
#firewall-cmd --add-service=ftp --permanent
永久關閉
#firewall-cmd --remove-service=ftp --permanent
success

讓設定生效
#systemctl restart firewalld

檢視設定是否生效
#iptables -L -n | grep 21
ACCEPTtcp--0.0.0.0/00.0.0.0/0tcp dpt:21 ctstate NEW

檢查防火牆狀態
#firewall-cmd --state
running

#systemctl stop firewalld
#firewall-cmd --state
not running


#firewall-cmd --list-all
public (default)
interfaces:
sources:
services: dhcpv6-client ftp ssh
ports:
masquerade: no
forward-ports:
icmp-blocks:
rich rules:

在 FirewallD 的服務名稱
#firewall-cmd --get-service
amanda-client bacula bacula-client dhcp dhcpv6 dhcpv6-client dns ftp high-availability http https imaps ipp ipp-client ipsec kerberos kpasswd ldap ldaps libvirt libvirt-tls mdns mountd ms-wbt MysqL nfs ntp openvpn pmcd pmproxy pmwebapi pmwebapis pop3s postgresql proxy-dhcp radius rpc-bind samba samba-client smtp ssh telnet tftp tftp-client transmission-client vnc-server wbem-https

查詢服務的啟用狀態
#firewall-cmd --query-service ftp
yes
#firewall-cmd --query-service ssh
yes
#firewall-cmd --query-service samba
no
#firewall-cmd --query-service http
no

自行加入要開放的 Port
#firewall-cmd --add-port=3128/tcp
#firewall-cmd --list-all
public (default)
interfaces:
sources:
services: dhcpv6-client ftp ssh
ports:3128/tcp
masquerade: no
forward-ports:
icmp-blocks:
rich rules: