PATH=/sbin:/bin:/usr/bin:/usr/sbin DAEMON=/usr/sbin/chronyd PIDFILE=/var/run/chronyd.pid 啥意思

这是一段关于Linux系统中的路径设置和守护进程配置的文本。

1. `PATH=/sbin:/bin:/usr/bin:/usr/sbin`：这是一个环境变量，用于指定系统在查找可执行文件时搜索的目录列表。在这个例子中，系统会按照这个顺序在这些目录下查找可执行文件。

2. `DAEMON=/usr/sbin/chronyd`：这是一个变量，用于指定守护进程（daemon）的路径。在这个例子中，守护进程是`/usr/sbin/chronyd`。

3. `PIDFILE=/var/run/chronyd.pid`：这是一个变量，用于指定守护进程的进程ID文件（PID file）的路径。在这个例子中，进程ID文件是`/var/run/chronyd.pid`。

相关问题

给我一份nginx通过/etc/init.d的启动脚本

以下是一个简单的nginx通过/etc/init.d的启动脚本：

#!/bin/sh
### BEGIN INIT INFO
# Provides:          nginx
# Required-Start:    $all
# Required-Stop:     $all
# Default-Start:     2 3 4 5
# Default-Stop:      0 1 6
# Short-Description: nginx web server
# Description:       nginx is a high-performance web server and reverse proxy.
### END INIT INFO

# Author: Your Name <your.email@example.com>

PATH=/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin
DAEMON=/usr/sbin/nginx
NAME=nginx
DESC=nginx

# Check if binary exists
test -x $DAEMON || exit 0

# Load the VERBOSE setting and other rcS variables
. /lib/init/vars.sh

# Define LSB log_* functions.
# Depend on lsb-base (>= 3.2-14) to ensure that this file is present.
. /lib/lsb/init-functions

# Include nginx defaults if available
if [ -f /etc/default/nginx ] ; then
        . /etc/default/nginx
fi

# Function that starts the daemon/service
do_start()
{
        # Return
        #   0 if daemon has been started
        #   1 if daemon was already running
        #   2 if daemon could not be started
        start-stop-daemon --start --quiet --pidfile /var/run/$NAME.pid \
                --exec $DAEMON --test > /dev/null \
                || return 1
        start-stop-daemon --start --quiet --pidfile /var/run/$NAME.pid \
                --exec $DAEMON -- \
                $DAEMON_OPTS \
                || return 2
}

# Function that stops the daemon/service
do_stop()
{
        # Return
        #   0 if daemon has been stopped
        #   1 if daemon was already stopped
        #   2 if daemon could not be stopped
        #   other if a failure occurred
        start-stop-daemon --stop --quiet --retry=TERM/30/KILL/5 --pidfile /var/run/$NAME.pid
        RETVAL="$?"
        [ "$RETVAL" = 2 ] && return 2
        # Wait for children to finish too if this is a daemon that forks
        # and if the daemon is only ever run from this initscript.
        # If the above conditions are not satisfied then add some other code
        # that waits for the process to drop all resources that could be
        # needed by services started subsequently.  A last resort is to
        # sleep for some time.
        start-stop-daemon --stop --quiet --oknodo --retry=0/30/KILL/5 --exec $DAEMON
        [ "$?" = 2 ] && return 2
        # Many daemons don't delete their pidfiles when they exit.
        rm -f /var/run/$NAME.pid
        return "$RETVAL"
}

# Function that sends a SIGHUP to the daemon/service
do_reload() {
        start-stop-daemon --stop --signal HUP --quiet --pidfile /var/run/$NAME.pid \
            --exec $DAEMON --name $NAME
        return 0
}

# Function that returns the status of the daemon/service
do_status() {
        status_of_proc -p /var/run/$NAME.pid "$DAEMON" "$NAME" && exit 0 || exit $?
}

case "$1" in
  start)
        [ "$VERBOSE" != no ] && log_daemon_msg "Starting $DESC" "$NAME"
        do_start
        case "$?" in
                0|1) [ "$VERBOSE" != no ] && log_end_msg 0 ;;
                2) [ "$VERBOSE" != no ] && log_end_msg 1 ;;
        esac
        ;;
  stop)
        [ "$VERBOSE" != no ] && log_daemon_msg "Stopping $DESC" "$NAME"
        do_stop
        case "$?" in
                0|1) [ "$VERBOSE" != no ] && log_end_msg 0 ;;
                2) [ "$VERBOSE" != no ] && log_end_msg 1 ;;
        esac
        ;;
  status)
        do_status
        ;;
  restart|force-reload)
        log_daemon_msg "Restarting $DESC" "$NAME"
        do_stop
        case "$?" in
          0|1)
                do_start
                case "$?" in
                        0) log_end_msg 0 ;;
                        1) log_end_msg 1 ;; # Old process is still running
                        *) log_end_msg 1 ;; # Failed to start
                esac
                ;;
          *)
                # Failed to stop
                log_end_msg 1
                ;;
        esac
        ;;
  reload)
        log_daemon_msg "Reloading $DESC" "$NAME"
        do_reload
        log_end_msg $?
        ;;
  *)
        echo "Usage: $SCRIPTNAME {start|stop|status|restart|reload|force-reload}" >&2
        exit 3
        ;;
esac

exit 0

将此脚本保存到/etc/init.d/nginx，并确保其可执行。之后你就可以使用以下命令启动、停止、重启和检查状态：

sudo service nginx start
sudo service nginx stop
sudo service nginx restart
sudo service nginx status

● nginx.service - A high performance web server and a reverse proxy server Loaded: loaded (/lib/systemd/system/nginx.service; enabled; vendor preset: enabled) Active: failed (Result: exit-code) since Thu 2023-06-01 15:30:44 CST; 21s ago Docs: man:nginx(8) Process: 16533 ExecStop=/sbin/start-stop-daemon --quiet --stop --retry QUIT/5 --pidfile /run/nginx.pid (code=exited, status=0/SUCCESS) Process: 16794 ExecStartPre=/usr/sbin/nginx -t -q -g daemon on; master_process on; (code=exited, status=1/FAILURE) Main PID: 16377 (code=exited, status=0/SUCCESS) Jun 01 15:30:44 ubuntu systemd[1]: Starting A high performance web server and a reverse proxy server... Jun 01 15:30:44 ubuntu nginx[16794]: nginx: [emerg] "server" directive is not allowed here in /etc/nginx/nginx.conf:87 Jun 01 15:30:44 ubuntu nginx[16794]: nginx: configuration file /etc/nginx/nginx.conf test failed Jun 01 15:30:44 ubuntu systemd[1]: nginx.service: Control process exited, code=exited status=1 Jun 01 15:30:44 ubuntu systemd[1]: nginx.service: Failed with result 'exit-code'. Jun 01 15:30:44 ubuntu systemd[1]: Failed to start A high performance web server and a reverse proxy server.

根据错误信息，你的Nginx配置文件中存在语法错误，导致Nginx服务启动失败。具体来说，错误信息显示在/etc/nginx/nginx.conf文件的第87行，其中包含了一个不允许在此处使用的"server"指令。

你需要打开/etc/nginx/nginx.conf文件，并检查第87行的语法是否正确。可能需要注意的是，Nginx配置文件中的指令是有一定的嵌套关系的，因此你需要确保"server"指令的位置是正确的，如果在错误的位置使用"server"指令，就会导致语法错误。

在修改之后，你需要保存文件并检查语法是否正确。可以使用以下命令来检查Nginx配置文件的语法：

sudo nginx -t

如果语法正确，则命令将不会输出任何信息。如果存在语法错误，则命令将会给出相应的错误信息，你需要根据错误信息进行修正。完成修正之后，你需要重启Nginx服务，使新的配置文件生效。