-查看所有已启动的服务

systemctl list-units --type=service

1.建立服务文件

vim /usr/lib/systemd/system/nginx.service 

nginx.service
[Unit]
Description=nginx - high performance web server
After=network.target remote-fs.target nss-lookup.target
[Service]
Type=forking
ExecStart=/usr/local/nginx/sbin/nginx -c /usr/local/nginx/conf/nginx.conf
ExecReload=/usr/local/nginx/sbin/nginx -s reload
ExecStop=/usr/local/nginx/sbin/nginx -s stop
[Install]
WantedBy=multi-user.target

mysql.service
[Unit]
Description=mysql
After=network.target remote-fs.target nss-lookup.target
[Service]
Type=forking
ExecStart=/usr/local/mysql/support-files/mysql.server start
#ExecReload=/usr/local/mysql/support-files/mysql.server restart
#ExecStop=/usr/local/mysql/support-files/mysql.server stop
#PrivateTmp=true
[Install]
WantedBy=multi-user.target

php-fpm.service
[Unit]
Description=php
After=network.target remote-fs.target nss-lookup.target
[Service]
Type=forking
ExecStart=/usr/local/php/sbin/php-fpm
[Install]
WantedBy=multi-user.target

redis.service
[Unit]
Description=Redis
After=network.target remote-fs.target nss-lookup.target
[Service]
Type=forking
ExecStart=/usr/local/bin/redis-server /etc/redis.conf
ExecStop=kill -INT `cat /tmp/redis.pid`
User=www
Group=www
[Install]
WantedBy=multi-user.target

supervisord.service
[Unit]
Description=Process Monitoring and Control Daemon
After=rc-local.service
[Service]
Type=forking
ExecStart=/usr/bin/supervisord -c /etc/supervisord.conf
SysVStartPriority=99
[Install]
WantedBy=multi-user.target

---文件内容解释

[Unit]:服务的说明

Description:描述服务

After:描述服务类别

[Service]服务运行参数的设置

Type=forking是后台运行的形式

ExecStart为服务的具体运行命令

ExecReload为重启命令

ExecStop为停止命令

PrivateTmp=True表示给服务分配独立的临时空间

注意：启动、重启、停止命令全部要求使用绝对路径

[Install]服务安装的相关设置，可设置为多用户

2.以754的权限保存在目录

chmod -R 754  /usr/lib/systemd/system 

服务systemctl脚本存放在：/usr/lib/systemd/，有系统（system）和用户（user）之分，

需要开机不登陆就能运行的程序，存在系统服务里，即：/usr/lib/systemd/system目录下

每一个服务以.service结尾，一般会分为3部分：[Unit]、[Service]和[Install]

3.设置开机自启动

-任意目录下执行

systemctl enable nginx.service 

4.其他命令

---启动nginx服务

systemctl start nginx.service

---设置开机自启动

systemctl enable nginx.service

---停止开机自启动

systemctl disable nginx.service

---查看服务当前状态

systemctl status nginx.service

---重新启动服务

systemctl restart nginx.service

===================

systemctl restart swoole-prod

systemctl stop swoole-prod

systemctl status swoole-prod

vim  /usr/lib/systemd/system/swoole-prod.service

[Unit]
Description=Prod Socket Server
After=network.target
After=syslog.target
[Service]
User=www
Type=simple
LimitNOFILE=65535
ExecStart=/usr/local/webserver/php-56/bin/php /data/web/dcms.qianbitou.cn/yii websocket/start
ExecReload=/bin/kill -USR1 $MAINPID
Restart=always
StandardOutput=syslog
StandardError=syslog
SyslogIdentifier=swoole-prod
[Install]
WantedBy=multi-user.target graphical.target