nginx服务和对应端口的那些事

优雅平滑重启nginx服务发现报错：

[[email protected] conf]# /application/nginx/sbin/nginx -s reload
nginx: [error] open() "/application/nginx-1.6.3//logs/nginx.pid" failed (2: No such file or directory)

    经过查看nginx服务未启动导致的，-s reload平滑优雅重启必须在nginx服务启动的状态才可以重启，就好像电脑还没有开机，你根本找不到重启的按钮。重启是建立在已经启动的状态的。



    判断nginx服务器是否启动？

1 根据nginx服务对应的进程是否存在判断，如下图查看没有nginx服务对应的进程

[[email protected] conf]# ps -ef|grep nginx

root       1437   1313  0 10:36 pts/1    00:00:00 grep nginx

2 根据nginx服务对应的端口是否存在监听

[[email protected] conf]# lsof -i :80
[[email protected] conf]#
[[email protected] conf]# netstat -lntup|grep nginx
[[email protected] conf]#
[[email protected] conf]# netstat -lntup|grep 80
[[email protected] conf]#

启动nginx服务后再查看：

[[email protected] conf]# /application/nginx/sbin/nginx
查看nginx进程是否存在：

[[email protected] conf]# ps -ef|grep nginx

root       1444      1  0 10:40 ?        00:00:00 nginx: master process /application/nginx/sbin/nginx
www        1445   1444  0 10:40 ?        00:00:00 nginx: worker process        
root       1456   1313  0 10:40 pts/1    00:00:00 grep nginx

[[email protected] conf]#
查看端口是否存在：
[[email protected] conf]# lsof -i :80

COMMAND  PID USER   FD   TYPE DEVICE SIZE/OFF NODE NAME
nginx   1444 root    6u  IPv4  12531      0t0  TCP *:http (LISTEN)
nginx   1445  www    6u  IPv4  12531      0t0  TCP *:http (LISTEN)

[[email protected] conf]# netstat -lntup|grep nginx

tcp        0      0 0.0.0.0:80                  0.0.0.0:*                   LISTEN      1444/nginx          
tcp        0      0 0.0.0.0:81                  0.0.0.0:*                   LISTEN      1444/nginx          
tcp        0      0 0.0.0.0:82                  0.0.0.0:*                   LISTEN      1444/nginx

[[email protected] conf]# netstat -lntup|grep 80

tcp        0      0 0.0.0.0:80                  0.0.0.0:*                   LISTEN      1444/nginx    

[[email protected] conf]# netstat -lntup|grep 81
tcp 0 0 0.0.0.0:81 0.0.0.0:* LISTEN 1444/nginx
[[email protected] conf]# netstat -lntup|grep 82

tcp        0      0 0.0.0.0:82                  0.0.0.0:*                   LISTEN      1444/nginx

目前nginx服务已经确定好启动了，那么继续执行优雅平滑重启，就不会报错。

[[email protected] conf]# /application/nginx/sbin/nginx -s reload
[[email protected] conf]#