一、配置防火牆，開啟80埠、3306埠

 CentOS 7.0預設使用的是firewall作為防火牆，這裡改為iptables防火牆。

1、關閉firewall：

systemctl stop firewalld.service #停止firewall

systemctl disable firewalld.service #禁止firewall開機啟動

1)安裝iptables

#先檢查是否安裝了iptables
service iptables status
#安裝iptables
yum install -y iptables
#升級iptables
 

yum update iptables 
#安裝iptables-services
yum install iptables-services

2)編輯防火牆配置檔案 
vi /etc/sysconfig/iptables 

# Firewall configuration written by system-config-firewall

# Manual customization of this file is not recommended.

*filter

:INPUT ACCEPT [0:0]

:FORWARD ACCEPT [0:0]

:OUTPUT ACCEPT [0:0]

-A INPUT -m state --state ESTABLISHED,RELATED -j ACCEPT

-A INPUT -p icmp -j ACCEPT

-A INPUT -i lo -j ACCEPT

-A INPUT -m state --state NEW -m tcp -p tcp --dport 22 -j ACCEPT

-A INPUT -m state --state NEW -m tcp -p tcp --dport 80 -j ACCEPT

-A INPUT -m state --state NEW -m tcp -p tcp --dport 3306 -j ACCEPT

-A INPUT -j REJECT --reject-with icmp-host-prohibited

-A FORWARD -j REJECT --reject-with icmp-host-prohibited

COMMIT

:wq! #儲存退出 

systemctl restart iptables.service #最後重啟防火牆使配置生效 

systemctl enable iptables.service #設定防火牆開機啟動

vi /etc/selinux/config

#SELINUX=enforcing #註釋掉

#SELINUXTYPE=targeted #註釋掉

SELINUX=disabled #增加

:wq! #儲存退出

setenforce 0 #使配置立即生效