centos下httpd 启动失败的解决办法

[root@csit yang]# service httpd start
Starting httpd:                                            [FAILED]

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[root@csit httpd]# cd /etc/httpd/conf.d/    #进入配置文件目录
[root@csit conf.d]$ grep NSSEngine *    #查找配置选项，并且知道在 nss.conf 这个文件中
nss.conf:NSSEngine on
[root@csit conf.d]$ vi  nss.conf    #注释NSSEngine
#   SSL Engine Switch:
#   Enable/Disable SSL for this virtual host.
#NSSEngine on

[root@csit httpd]# service httpd restart
Stopping httpd:                                            [  OK  ]
Starting httpd:                                              [  OK  ]