mysql的安装，关于/etc/init.d/下没有mysqld的命令，及php与mysql的连接测试

yum install php php-mysql mysql 

yum install mysql-server //这个必须安装，才会有/etc/init.d的mysqld

mysql 使用的端口为3306

注意1.我们验证php程序执行环境

    方法，在DoucumentRoot路径下建个test.php文件

        <?php

            phpinfo();

        ?>

    用浏览器浏览后有php的页面显示。

    2.测试php程序与mysql通信

    方法，在 test.php文件中修改

            $link = mysql_connect('127.0.0.1','root','');

            if(!$link){

                die("datebase connect error:".mysql_error());//连接不上输出错误注意点

            }

            else

                echo "Success";

        ?>       

    若出现报错：SQLSTATE[HY000] [2003] Can't connect to MySQL server on 'XXX' (13)

            这是SELinux不允许访问外网，

            简单点就可以使用setenfroce=0;就可以了。

或者： 使用命令getsebool - get SELinux boolean value(s)

命令 getsebool -a | grep httpd                                  

allow_httpd_anon_write --> off

allow_httpd_mod_auth_ntlm_winbind --> off

allow_httpd_mod_auth_pam --> off

allow_httpd_sys_script_anon_write --> off

httpd_builtin_scripting --> on

httpd_can_check_spam --> off

httpd_can_network_connect --> off

httpd_can_network_connect_cobbler --> off

httpd_can_network_connect_db --> off

httpd_can_network_memcache --> off

httpd_can_network_relay --> off

httpd_can_sendmail --> off

httpd_dbus_avahi --> on

httpd_dbus_sssd --> off

httpd_enable_cgi --> on

httpd_enable_ftp_server --> off

httpd_enable_homedirs --> off

httpd_execmem --> off

httpd_manage_ipa --> off

httpd_read_user_content --> off

httpd_run_preupgrade --> off

httpd_run_stickshift --> off

httpd_serve_cobbler_files --> off

httpd_setrlimit --> off

httpd_ssi_exec --> off

httpd_tmp_exec --> off

httpd_tty_comm --> on

httpd_unified --> on

httpd_use_cifs --> off

httpd_use_fusefs --> off

httpd_use_gpg --> off

httpd_use_nfs --> off

httpd_use_openstack --> off

httpd_verify_dns --> off

注意这里httpd_can_network_connect --> off

这里设置使用命令setsebool httpd_can_network_connect 1

    PS:   1. 若出现错误 Lost connection to MySQL server at 'reading initial communication packet', system error: 111

        有可能是mysql服务没打开，可用命令service mysqld start

      2.若出现错误ERROR 2003 (HY000): Can't connect to MySQL server on '192.168.18.9' (113)

        很可能是防火墙的问题

        iptables -F

        iptables -L

<b>这样就解决了</b>

<b></b>

<b>本文转自 神迹难觅 51CTO博客，原文链接：http://blog.51cto.com/ji123/1951888，如需转载请自行联系原作者</b>