问题：
监控短信发出网站的所有的网址突然无法访问。
首先尝试访问几个网址测试，测试了几个都是如此。判断后台的程序出现问题。
1.查看端口是否正常:netstat -tunlp | grep 80
2.查看服务是否正常：ps -ef | grep httpd
端口及服务都没有在运行。
尝试运行服务:/wdlinux/httpd/bin/apachectl start
启动报错
[[email protected] lib64]#/wdlinux/httpd/bin/apachectl start
httpd: Syntax error on line 152 of /wdlinux/httpd/conf/httpd.conf: Cannot load modules/libphp5.so into server: libmcrypt.so.4: cannot open shared object file: No such file or directory
查看libphp5.so正常
[[email protected] modules]#ls -lh libphp5.so
-rwxr-xr-x 1 root root 42M Nov 29 10:23 libphp5.so
查看libmcrypt.so.4亮红色报错
[[email protected] modules]#ls -lh libmcrypt.so.4
lrwxrwxrwx 1 root root 36 Feb 5 19:16 libmcrypt.so.4 -> /usr/lib64//usr/lib64/libmcrypt.so.4
切换目录:/usr/lib64
查看libmcrpt发现文件不存在
[[email protected] lib64]# `ls -lh libmcrypt`
lrwxrwxrwx 1 root root 18 Nov 29 09:50 libmcrypt.so -> libmcrypt.so.4.4.8
rpm查询文件已经安装
[[email protected] init.d]#rpm -qa libmcrypt*
libmcrypt-devel-2.5.8-13.el7.x86_64
libmcrypt-2.5.8-13.el7.x86_64
确定程序包已经损坏
重新安装yum
[[email protected] ~]# yum reinstall libmcrypt -y
启动apache
/wdlinux/httpd/bin/apachectl start
Starting httpd: [ OK ]
原文地址：http://blog.51cto.com/hongdouzi555/2069149