問題：
監控短信發出網站的所有的網址突然無法訪問。
首先嚐試訪問幾個網址測試，測試了幾個都是如此。判斷後臺的程序出現問題。
1.查看端口是否正常:netstat -tunlp | grep 80
2.查看服務是否正常：ps -ef | grep httpd
端口及服務都沒有在運行。
嘗試運行服務:/wdlinux/httpd/bin/apachectl start
啓動報錯
[root@nginx-01 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
[root@nginx-01 modules]#ls -lh libphp5.so
-rwxr-xr-x 1 root root 42M Nov 29 10:23 libphp5.so
查看libmcrypt.so.4亮紅色報錯
[root@nginx-01 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
切換目錄:/usr/lib64
查看libmcrpt發現文件不存在
[root@nginx-01 lib64]# `ls -lh libmcrypt`
lrwxrwxrwx 1 root root 18 Nov 29 09:50 libmcrypt.so -> libmcrypt.so.4.4.8
rpm查詢文件已經安裝
[root@nginx-01 init.d]#rpm -qa libmcrypt*
libmcrypt-devel-2.5.8-13.el7.x86_64
libmcrypt-2.5.8-13.el7.x86_64
確定程序包已經損壞
重新安裝yum
[root@nginx-01 ~]# yum reinstall libmcrypt -y
啓動apache
/wdlinux/httpd/bin/apachectl start
Starting httpd: [ OK ]