咋回事啊，安装了httpd启动不了

[root@iZwz9b6v2187dykzsgbxctZ ~]# service httpd start
Starting httpd: httpd: Could not reliably determine the server's fully qualified domain name, using 172.18.130.101 for ServerName
(98)Address already in use: make_sock: could not bind to address 0.0.0.0:80
no listening sockets available, shutting down
Unable to open logs
                                                           [FAILED]
[root@iZwz9b6v2187dykzsgbxctZ ~]# netstat -lnp|grep 80
tcp        0      0 0.0.0.0:80                  0.0.0.0:*                   LISTEN      10642/nginx