systemctl实现定时任务(比crontab好用）

假设有一个 kline_dumper的服务，想实现每隔10分钟自动启动/停止，使用crontab可以很简单的实现，使用systemctl也能够方便的实现；

一、准备工作
1、创建 kline_dumper.service

[Unit]
Description=Kline Dumper service[Service]
ExecStart=/opt/price/bin/kline_dumper
Restart=on-failure
WorkingDirectory=/opt/price/bin  --flagfile=/opt/price/bin/config/price.flags
StandardOutput=journal
StandardError=journal[Install]
WantedBy=multi-user.target

2、创建 kline_dumper-restart.service 和 kline_dumper-restart.timer
kline_dumper-restart.service:

[Unit]
Description=Restart kline_dumper with delay[Service]
Type=oneshot
ExecStart=/bin/bash -c '/bin/systemctl stop kline_dumper.service && sleep 10 && /bin/systemctl start kline_dumper.service'

kline_dumper-restart.timer

[Unit]
Description=Restart kline_dumper every 10 minutes[Timer]
OnCalendar=*:0/10
AccuracySec=1s
Unit=kline_dumper-restart.service[Install]
WantedBy=timers.target

把这些文件copy到 /etc/systemd/system目录

二、使用配置
1、执行下面的命令：

sudo systemctl daemon-reload
sudo systemctl enable --now kline_dumper.service
sudo systemctl enable --now kline_dumper-restart.timer

2、检查状态：

systemctl list-timers --all | grep kline_dumper
systemctl status kline_dumper-restart.timer

如果运行正常，刚一般会看到下面的输出：

● kline_dumper-restart.timer - Restart kline_dumper every 10 minutesLoaded: loaded (/etc/systemd/system/kline_dumper-restart.timer; enabled)Active: active (waiting) since ...Trigger: Fri 2025-05-30 14:20:00 CST; 5min left

当然，也可以像下面这样查看日志：

journalctl -u kline_dumper.service
journalctl -u kline_dumper-restart.service