2.Nginx日常维护技巧

Nginx日常维护技巧

1. Nginx配置正确性检查

nginx提供了配置文件调试功能，可以快速定义配置文件存在的问题。执行如下命令检测配置文件的正确性：

[root@localhost 桌面]# which nginx

/usr/local/nginx/sbin/nginx

我把nginx命令的路径写入到PATH里面，所以在执行nginx这条命令的时候我就不需要写绝对路径：

[root@localhost 桌面]# nginx –t                                                                                                         -t      检查配置文件的正确性

nginx: the configuration file /usr/local/nginx//conf/nginx.conf syntax is ok

nginx: [warn] 65535 worker_connections exceed open file resource limit: 32768

nginx: configuration file /usr/local/nginx//conf/nginx.conf test is successful

[root@localhost 桌面]# nginx -t -c /usr/local/nginx/conf/nginx.conf                                         -c      制定nginx配置文件的路径，默认为/usr/local/nginx/conf/nginx.conf

nginx: the configuration file /usr/local/nginx/conf/nginx.conf syntax is ok

nginx: [warn] 65535 worker_connections exceed open file resource limit: 32768

nginx: configuration file /usr/local/nginx/conf/nginx.conf test is successful

另外，nginx也提供了查看版本信息和相关编译信息的功能：

[root@localhost 桌面]# nginx -v

nginx version: nginx/1.2.1

[root@localhost 桌面]# nginx -V

nginx version: nginx/1.2.1

configure arguments: --prefix=/usr/local/nginx/ --with-http_stub_status_module --with-http_gzip_static_module --user=www --group=www

1. Nginx的启动，关闭，和重启

nginx对进程的控制能力非常强大，可以通过信号命令控制进程。常用的信号有：

QUIT：表示处理完当前请求后关闭

HUP：表示重新加载配置，即关闭原有的进程开启新的工作进程。此操作不会用端用户的访问请求，因此，可以通过此信号平滑的重启nginx。

USR1：用于nginx的日志切换，也就是重新打开一个日志文件。例如：每天要生成一个新的日志文件的时候，可以使用这个信号老控制。

USR2：用于平滑升级可执行程序。

WINCH：从容关闭工作进程。

nginx的启动非常简单：

/usr/local/nginx/sbin/nginx

即可完成对nginx的启动。在nginx启动以后，我们可以查看到nginx的工作进程。

[root@localhost 桌面]# cat /usr/local/nginx/logs/nginx.pid

6597

如果我们要不间断的重启nginx服务，我们需要

kill –xxx    pid             #xxx就是信号名

如：

[root@localhost 桌面]# kill -HUP `cat /usr/local/nginx/logs/nginx.pid`

在实际生产中，我们需要为nginx写服务启动脚本：

#!/bin/bash

# nginx Startup script for the Nginx HTTP Server

# it is v.0.0.2 version.

# chkconfig: - 85 15

# description: Nginx is a high-performance web and proxy server.

# It has a lot of features, but it's not for everyone.

# processname: nginx

# pidfile: /var/run/nginx.pid

# config: /usr/local/nginx/conf/nginx.conf

nginxd=/usr/local/nginx/sbin/nginx

nginx_config=/usr/local/nginx/conf/nginx.conf

nginx_pid=/usr/local/nginx/logs/nginx.pid

RETVAL=0

prog="nginx"

# Source function library.

. /etc/rc.d/init.d/functions

# Source networking configuration.

. /etc/sysconfig/network

# Check that networking is up.

[ ${NETWORKING} = "no" ] && exit 0

[ -x $nginxd ] || exit 0

# Start nginx daemons functions.

start() {

if [ -e $nginx_pid ];then

echo "nginx already running...."

exit 1

fi

echo -n $"Starting $prog: "

daemon $nginxd -c ${nginx_config}

RETVAL=$?

echo

[ $RETVAL = 0 ] && touch /var/lock/subsys/nginx

return $RETVAL

}

# Stop nginx daemons functions.

stop() {

echo -n $"Stopping $prog: "

killproc $nginxd

RETVAL=$?

echo

[ $RETVAL = 0 ] && rm -f /var/lock/subsys/nginx /usr/local/nginx/logs/nginx.pid

}

reload() {

echo -n $"Reloading $prog: "

#kill -HUP `cat ${nginx_pid}`

killproc $nginxd -HUP

RETVAL=$?

echo

}

# See how we were called.

case "$1" in

start)

start

;;

stop)

stop

;;

reload)

reload

;;

restart)

stop

start

;;

status)

status $prog

RETVAL=$?

;;

*)

echo $"Usage: $prog {start|stop|restart|reload|status|help}"

exit 1

esac

exit $RETVAL

1.Nginx服务应用