一、背景介绍

1、加入系统服务

CentOS7: systemctl restart xxxx
CentOS6: service xxxxx restart

目录文件存放在

/usr/lib/systemd/system

比如：/usr/lib/systemd/system/php-fpm.service

[root@zjt-ecs-1 system]# cat  /usr/lib/systemd/system/php-fpm.service 
# It's not recommended to modify this file in-place, because it
# will be overwritten during upgrades.  If you want to customize,
# the best way is to use the "systemctl edit" command.
[Unit]
Description=The PHP FastCGI Process Manager
After=network.target
[Service]
Type=simple
PIDFile=/usr/local/php/var/run/php-fpm.pid
ExecStart=/usr/local/php/sbin/php-fpm --nodaemonize --fpm-config /usr/local/php/etc/php-fpm.conf
ExecReload=/bin/kill -USR2 $MAINPID
PrivateTmp=true
[Install]
WantedBy=multi-user.target

[Unit]
Description=nginx - high performance web server
Documentation=http://nginx.org/en/docs/
After=network-online.target remote-fs.target nss-lookup.target
Wants=network-online.target
[Service]
Type=forking
PIDFile=/var/run/nginx.pid
ExecStart=/usr/sbin/nginx -c /etc/nginx/nginx.conf
ExecReload=/bin/sh -c "/bin/kill -s HUP $(/bin/cat /var/run/nginx.pid)"
ExecStop=/bin/sh -c "/bin/kill -s TERM $(/bin/cat /var/run/nginx.pid)"
[Install]
WantedBy=multi-user.target
~

系统服务目录

2、文件说明

i386是指386上编译的，386以上机器可以安装。i586以此类推。
有的rpm包是在红帽子下编译的，有的是在其他平台下编译的，含有noarch的包说明，你可以在任何平台上安装这个软件包，就是说它并不依赖于哪个特定的linux发布版。
noarch是no architecture的意思，表示这个包可以在各种不同cpu的电脑上通用

二、配置

目录

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

三、使文件生效

systemctl daemon-reload

五、操作命令

CentOS7: systemctl restart mysql 
CentOS6: service mysql restart
启动
systemctl start nginx
systemctl start mysql
systemctl start xxxx
关闭
systemctl stop nginx
systemctl stop mysqld
systemctl stop xxxx
重启nginx
systemctl restart nginx
systemctl restart mysqld
systemctl restart xxxx
状态
systemctl status nginx
systemctl status mysqld
systemctl status xxxx