在/usr/lib/systemd/system/ 或者 /etc/systemd/system/ 目录创建 .service  文件

/lib/systemd/system/与/etc/systemd/system/的区别 - 简书

mysqld.service

[Unit]
Description=MySQL Server
Documentation=man:mysqld(8)
Documentation=http://dev.mysql.com/doc/refman/en/using-systemd.html
After=network.target
After=syslog.target

[Install]
WantedBy=multi-user.target

[Service]
User=mysql
Group=mysql

Type=forking

PIDFile=/var/run/mysqld/mysqld.pid

# Disable service start and stop timeout logic of systemd for mysqld service.
TimeoutSec=0

# Execute pre and post scripts as root
PermissionsStartOnly=true

# Needed to create system tables
ExecStartPre=/usr/bin/mysqld_pre_systemd

# Start main service
ExecStart=/usr/sbin/mysqld --daemonize --pid-file=/var/run/mysqld/mysqld.pid $MYSQLD_OPTS

# Use this to switch malloc implementation
EnvironmentFile=-/etc/sysconfig/mysql

# Sets open_files_limit
LimitNOFILE = 65536
LimitNPROC = 65536

Restart=on-failure

RestartPreventExitStatus=1

PrivateTmp=false

redis.service

[Unit]
Description=redis-server
After=network.target
[Service]
Type=forking
ExecStart=/usr/local/redis/bin/redis-server /usr/local/redis/bin/redis.conf
PrivateTmp=true
[Install]
WantedBy=multi-user.target

nginx.service

[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

# 开机启动
systemctl enable mysqld

# 关闭开机启动
systemctl disable mysqld

设置服务为开机启动

systemctl enable mysqld
systemctl enable redis
systemctl enable nginx

查看是否设置成功

sudo systemctl list-unit-files | grep enabled

重启测试

测试mysql是否启动成功

netstat -na | grep 3306