安装lamp环境后，测试数据库连接。
当host使用127.0.0.1时，报错：(HY000/2002): Permission denied。
把host换成localhost后，又报错：SQLSTATE[HY000] [2002] No such file or directory。
最后发现是因为没有关闭selinux，通常情况下载安装完CentOS7后，默认情况下SElinux是启用状态。
[root@rdo ~]# sestatus SELinux status: enabled SELinuxfs mount: /sys/fs/selinux SELinux root directory: /etc/selinux Loaded policy name: targeted Current mode: enforcing Mode from config file: enforcing Policy MLS status: enabled Policy deny_unknown status: allowed Max kernel policy version: 28
如果要临时关闭，可以执行：
setenforce 0此时状态如下：
[root@rdo ~]# sestatus SELinux status: enabled SELinuxfs mount: /sys/fs/selinux SELinux root directory: /etc/selinux Loaded policy name: targeted Current mode: permissive Mode from config file: enforcing Policy MLS status: enabled Policy deny_unknown status: allowed Max kernel policy version: 28
如果要永久关闭，可以修改配置文件/etc/selinux/config，将SELINU置为disabled。
[root@rdo ~]# cat /etc/selinux/config # This file controls the state of SELinux on the system. # SELINUX= can take one of these three values: # enforcing - SELinux security policy is enforced. # permissive - SELinux prints warnings instead of enforcing. # disabled - No SELinux policy is loaded. #SELINUX=enforcing SELINUX=disabled # SELINUXTYPE= can take one of three two values: # targeted - Targeted processes are protected, # minimum - Modification of targeted policy. Only selected processes are protected. # mls - Multi Level Security protection. SELINUXTYPE=targeted
修改该配置文件也可以执行下面的命令来完成：
sed -i '/SELINUX/s/enforcing/disabled/' /etc/selinux/config
修改完成后，保存重启，重启后状态如下：
[root@rdo ~]# sestatus SELinux status: disabled
文章本人亲测有效。
文章转载：https://blog.csdn.net/eclothy/article/details/48265445