问题：
使用命令：/usr/local/nginx/sbin/nginx -s reload 重启nginx出现报错，报错如下
nginx: [error] open() “/usr/local/nginx/logs/nginx.pid” failed (2: No such file or directory)
报错说的是：打开/usr/local/nginx/logs/nginx.pid失败，没有这样的文件或目录，应该是logs目录下没有nginx.pid这个文件。

解决方法：
重新指定启动之时加载的配置文件，然后再重启。

例如nginx的配置文件目录是：/usr/local/nginx/conf/nginx.conf

先执行平滑启动nginx命令：

/usr/local/nginx/sbin/nginx  -c /usr/local/nginx/conf/nginx.conf

然后再执行重启nginx命令：

/usr/local/nginx/sbin/nginx -s reload

进行平滑重启nginx就不会出现报错提示了

实例如下：

[root@localhost ~]# /usr/local/nginx/sbin/nginx -s stop
[root@localhost ~]# /usr/local/nginx/sbin/nginx -s reload
nginx: [error] open() "/usr/local/nginx/logs/nginx.pid" failed (2: No such file or directory)
[root@localhost ~]# netstat -atunp
Active Internet connections (servers and established)
Proto Recv-Q Send-Q Local Address           Foreign Address         State       PID/Program name
tcp        0      0 0.0.0.0:22              0.0.0.0:*               LISTEN      1325/sshd
tcp        0      0 127.0.0.1:25            0.0.0.0:*               LISTEN      1793/master
tcp        0      0 192.168.41.191:22       192.168.41.119:55080    ESTABLISHED 9925/sshd: root@not
tcp        0      0 192.168.41.191:22       192.168.41.119:62664    ESTABLISHED 9983/sshd: root@not
tcp        0      0 192.168.41.191:22       192.168.41.119:55077    ESTABLISHED 9920/sshd: root@pts
tcp        0     48 192.168.41.191:22       192.168.41.119:62657    ESTABLISHED 9977/sshd: root@pts
tcp6       0      0 :::22                   :::*                    LISTEN      1325/sshd
tcp6       0      0 ::1:25                  :::*                    LISTEN      1793/master
[root@localhost ~]# /usr/local/nginx/sbin/nginx -c /usr/local/nginx/conf/nginx.conf
[root@localhost ~]# /usr/local/nginx/sbin/nginx -s reload
[root@localhost ~]# netstat -atunp
Active Internet connections (servers and established)
Proto Recv-Q Send-Q Local Address           Foreign Address         State       PID/Program name
tcp        0      0 0.0.0.0:80              0.0.0.0:*               LISTEN      17291/nginx: master
tcp        0      0 0.0.0.0:22              0.0.0.0:*               LISTEN      1325/sshd
tcp        0      0 127.0.0.1:25            0.0.0.0:*               LISTEN      1793/master
tcp        0      0 192.168.41.191:22       192.168.41.119:55080    ESTABLISHED 9925/sshd: root@not
tcp        0      0 192.168.41.191:22       192.168.41.119:62664    ESTABLISHED 9983/sshd: root@not
tcp        0      0 192.168.41.191:22       192.168.41.119:55077    ESTABLISHED 9920/sshd: root@pts
tcp        0     48 192.168.41.191:22       192.168.41.119:62657    ESTABLISHED 9977/sshd: root@pts
tcp6       0      0 :::22                   :::*                    LISTEN      1325/sshd
tcp6       0      0 ::1:25                  :::*                    LISTEN      1793/master