CentOS7编写systemd服务脚本

vim /usr/lib/systemd/system/xxx.service 
[Unit]   # 主要是服务说明
Description=test   # 简单描述服务
After=network.target    # 描述服务类别，表示本服务需要在network服务启动后在启动
Before=xxx.service      # 表示需要在某些服务启动之前启动，After和Before字段只涉及启动顺序，不涉及依赖关系。
 
[Service]  # 服务的关键
Type=forking     # 表示后台运行模式。
PIDFile=/usr/local/test/test.pid    # 存放PID的绝对路径
ExecStart=/usr/local/test/bin/startup.sh    # 服务启动命令，命令需要绝对路径
ExecReload=xxx  #为重启命令，
ExecStop=xxx   #为停止命令
PrivateTmp=true                               # 表示给服务分配独立的临时空间
   
[Install]   
WantedBy=multi-user.target  # 多用户

Type：定义启动时的进程行为。它有以下几种值。
Type=simple：默认值，执行ExecStart指定的命令，启动主进程
Type=forking：以 fork 方式从父进程创建子进程，创建后父进程会立即退出
Type=oneshot：一次性进程，Systemd 会等当前服务退出，再继续往下执行
Type=dbus：当前服务通过D-Bus启动
Type=notify：当前服务启动完毕，会通知Systemd，再继续往下执行
Type=idle：若有其他任务执行完毕，当前服务才会运行
ExecStart：启动当前服务的命令
ExecStartPre：启动当前服务之前执行的命令
ExecStartPost：启动当前服务之后执行的命令
ExecReload：重启当前服务时执行的命令
ExecStop：停止当前服务时执行的命令
ExecStopPost：停止当其服务之后执行的命令
RestartSec：自动重启当前服务间隔的秒数
Restart：定义何种情况 Systemd 会自动重启当前服务 
    no(默认值)： # 退出后无操作
    on-success:  # 只有正常退出时（退出状态码为0）,才会重启
    on-failure:  # 非正常退出时，重启，包括被信号终止和超时等
    on-abnormal: # 只有被信号终止或超时，才会重启
    on-abort:    # 只有在收到没有捕捉到的信号终止时，才会重启
    on-watchdog: # 超时退出时，才会重启
    always:      # 不管什么退出原因，都会重启（除了systemctl stop）
    # 对于守护进程，推荐用on-failure
KillMode的类型：
    control-group(默认)：# 当前控制组里的所有子进程，都会被杀掉
    process: # 只杀主进程
    mixed:   # 主进程将收到SIGTERM信号，子进程收到SIGKILL信号
    none:    # 没有进程会被杀掉，只是执行服务的stop命令
TimeoutSec：定义 Systemd 停止当前服务之前等待的秒数
Environment：指定环境变量

WantedBy：它的值是一个或多个 Target，当前 Unit 激活时（enable）符号链接会放入/etc/systemd/system目录下面以 Target 名 + .wants后缀构成的子目录中
    multi-user.target: # 表示多用户命令行状态，这个设置很重要
    graphical.target:  # 表示图形用户状体，它依赖于multi-user.target
RequiredBy：它的值是一个或多个 Target，当前 Unit 激活时，符号链接会放入/etc/systemd/system目录下面以 Target 名 + .required后缀构成的子目录中
Alias：当前 Unit 可用于启动的别名
Also：当前 Unit 激活（enable）时，会被同时激活的其他 Unit

[Unit]
Description=nginx
After=network.target
[Service]
Type=forking
PIDFile=/usr/local/nginx/logs/nginx.pid
ExecStart=/usr/local/nginx/sbin/nginx -c /usr/local/nginx/conf/nginx.conf
ExecStop=/usr/local/nginx/sbin/nginx -s stop -c /usr/local/nginx/conf/nginx.conf
ExecReload= /usr/local/nginx/sbin/nginx -s reload -c /usr/local/nginx/conf/nginx.conf
PrivateTmp=ture
[Install]
WantedBy=multi-user.target

#启动、停止服务
 systemctl start nginx.service 
 systemctl stop nginx.service 
 #重启服务
 systemctl reload nginx.service  #服务启动时重启有效
 systemctl restart nginx.service
 #查看nginx服务状态
 systemctl status nginx.service
 #添加服务到开机自启、取消开机自启
 systemctl enable nginx.service
 systemctl disable nginx.service

#!/bin/bash
#chkconfig: 2345 38 46

. /etc/init.d/functions
if [ $# -ne 1 ]
then
 echo "usage: $0 {start|stop|status}"
 exit 1
fi
case "$1" in
start)
 if [ -e "/var/run/inotify.pid" ]
 then
    action "inotify service start fail" /bin/false
    echo "sync server is running......"
    sleep 1
    exit 1
 fi
 /bin/bash /server/scripts/inotify.sh &
 `ps -ef|grep "inotifywait"|grep -v "grep"|awk '{print $2}'` >/var/run/inotify.pid
 if [ `ps -ef|grep inotify|wc -l` -gt 2 ]
 then
    action "inotify service is started" /bin/true
 else
    action "inotify service is started" /bin/false
 fi
 ;;
stop)
 if [ `ps -ef|grep inotify|grep -v grep|wc -l` -a -e "/var/run/inotify.pid" ]
 then
    rm -f /var/run/inotify.pid >/dev/null 2>&1
    pkill inotifywait
 else
    action "inotify service stop fail" /bin/false
    echo "sync server is not running"
    sleep 1
    exit 1
 fi
 sleep 1
 if [ `ps -ef|grep inotify|grep -v grep|wc -l` -eq 0 -a ! -e "/var/run/inotify.pid" ]
 then
    action "inotify service is stoped" /bin/true
 else
    action "inotify service is stoped" /bin/false
 fi
 ;;
status)
 if [ `ps -ef|grep inotify|wc -l` -gt 2 ]
 then
    action "inotify service is running"
 else
    action "inotify service is stoped"
 fi
 ;;
*)
 echo "usage: $0 {start|stop|status}"
 exit 1
esac

[Unit]
Description="这是rsync+inotify实时同步服务"
After=network.target remote-fs.target nss-lookup.target

[Service]
Type=forking
ExecStart=/bin/sh /server/scripts/sync.sh start
ExecReload=/bin/sh /server/scripts/sync.sh restart
ExecStop=/bin/sh /server/scripts/sync.sh stop
KillSignal=SIGQUIT
TimeoutStopSec=5
KillMode=process
PrivateTmp=true

[Install]
WantedBy=multi-user.target

#!/bin/bash

# chkconfig: 2345 10 90 
# description: myservice ....

#根据自己的情况替换some-progress为自己的进程名字
. /etc/init.d/functions
if [ $# -ne 1 ]
then
 echo "usage: $0 {start|stop|restart|status}"
 exit 1
fi

start() {
 if [ -n "$(ps -ef | grep "/some-progress"|grep -v grep|grep -v "log"|grep -v "some-progress.sh")" ];then
    action "some-progress service start fail" /bin/false
    echo "some-progress is running......"
    sleep 1
    exit 1
 fi
 cd /usr/local/dns/bin/
 nohup ./some-progress >/dev/null 2>&1 &
 ps -ef|grep "/some-progress"|grep -v "grep"|grep -v "log"|grep -v "some-progress.sh"|awk '{print $2}' >/var/run/some-progress.pid
 if [ `ps -ef | grep "/some-progress"|grep -v grep|grep -v "log"|grep -v "some-progress.sh"|wc -l` -eq 1 ];then
    action "some-progress service is started" /bin/true
 else
    action "some-progress service is started" /bin/false
 fi
}

stop() {
 if [ `ps -ef | grep "/some-progress"|grep -v grep|grep -v "log"|grep -v "some-progress.sh"|wc -l` -a -e "/var/run/some-progress.pid" ]
 then
    rm -f /var/run/some-progress.pid >/dev/null 2>&1
    ps -ef|grep "/some-progress"|grep -v "grep"|grep -v "log"|grep -v "some-progress.sh"|awk '{print $2}'|xargs kill -9
 else
    action "some-progress service stop fail" /bin/false
    echo "some-progress service is not running"
 fi
 sleep 1
 if [ `ps -ef|grep some-progress|grep -v grep|grep -v "log"|grep -v "some-progress.sh"|wc -l` -eq 0 -a ! -e "/var/run/some-progress.pid" ]
 then
    action "some-progress service is stoped" /bin/true
 else
    action "some-progress service is stoped" /bin/false
 fi
}


case "$1" in
start)
    start
    ;;
stop)
    stop
    ;;
restart)
    stop
    start
    ;;
status)
 if [ `ps -ef|grep some-progress|grep -v grep|grep -v "log"|grep -v "some-progress.sh"|wc -l` -eq 1 ]
 then
    action "some-progress service is running"
 else
    action "some-progress service is stoped"
 fi
 ;;
*)
 echo "usage: $0 {start|stop|restart|status}"
 exit 1
esac