使用 systemd timer 配置定时任务

云计算 2023-01-04 向阳逐梦手机阅读

1. 准备定时脚步

如果是 Bash 脚本，第一行需要指定解释器。

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mkdir -p /root/scripts
vim /root/scripts/quick-clear.sh

#!/bin/sh

/usr/local/bin/kubectl --kubeconfig /root/.kube/config get pods --all-namespaces -o wide | grep Evicted | awk '{print $1,$2}' | xargs --no-run-if-empty -L1 /usr/local/bin/kubectl --kubeconfig /root/.kube/config delete pod -n || true
/usr/local/bin/kubectl --kubeconfig /root/.kube/config get pods --all-namespaces -o wide | grep Error | awk '{print $1,$2}' | xargs --no-run-if-empty -L1 /usr/local/bin/kubectl --kubeconfig /root/.kube/config delete pod -n || true
/usr/local/bin/kubectl --kubeconfig /root/.kube/config get pods --all-namespaces -o wide | grep Completed | awk '{print $1,$2}' | xargs --no-run-if-empty -L1 /usr/local/bin/kubectl --kubeconfig /root/.kube/config delete pod -n || true
/usr/local/bin/kubectl --kubeconfig /root/.kube/config get pipelinerun --all-namespaces -o wide | grep Succeeded | awk '{print $1,$2}' | xargs --no-run-if-empty -L1 /usr/local/bin/kubectl --kubeconfig /root/.kube/config delete pipelinerun -n || true
/usr/local/bin/kubectl --kubeconfig /root/.kube/config get pipelinerun --all-namespaces -o wide | grep PipelineRunTimeout | awk '{print $1,$2}' | xargs --no-run-if-empty -L1 /usr/local/bin/kubectl --kubeconfig /root/.kube/config delete pipelinerun -n || true
/usr/local/bin/kubectl --kubeconfig /root/.kube/config get pipelinerun --all-namespaces -o wide | grep InvalidWorkspaceBindings | awk '{print $1,$2}' | xargs --no-run-if-empty -L1 /usr/local/bin/kubectl --kubeconfig /root/.kube/config delete pipelinerun -n || true
/usr/local/bin/kubectl --kubeconfig /root/.kube/config get pipelinerun --all-namespaces -o wide | grep Failed | awk '{print $1,$2}' | xargs --no-run-if-empty -L1 /usr/local/bin/kubectl --kubeconfig /root/.kube/config delete pipelinerun -n || true

/usr/local/bin/kubectl --kubeconfig /root/.kube/config describe -A pvc | grep -E "^Name:.*$|^Namespace:.*$|^Used By:.*$" | grep -B 2 "<none>" | grep -E "^Name:.*$|^Namespace:.*$" | cut -f2 -d: | paste -d " " - - | xargs --no-run-if-empty -n2 bash -c '/usr/local/bin/kubectl --kubeconfig /root/.kube/config -n ${1} delete pvc ${0}' || true

/usr/bin/docker images | grep none | awk '{print $3}' | xargs --no-run-if-empty /usr/bin/docker rmi || true
/usr/bin/docker images |grep -E "([0-9a-z]+[-]){3,}[0-9]{9}" |awk '{print $3}' | xargs --no-run-if-empty /usr/bin/docker rmi || true
/usr/bin/docker system prune -f || true

别忘了添加可执行权限。

`1`	`chmod +x /root/scripts/quick-clear.sh`

2. 添加 timer

`1`	`vim /etc/systemd/system/quick-clear.timer`

[Unit]
Description=clear every week

[Timer]
OnCalendar=*-*-* 5:00:00
Unit=quick-clear.service

[Install]
WantedBy=timers.target

在 [Timer] 中可以使用各种参数控制定时任务的执行周期：

OnActiveSec，定时器生效后，多少时间开始执行任务
OnBootSec，系统启动后，多少时间开始执行任务
OnStartupSec，Systemd 进程启动后，多少时间开始执行任务
OnUnitActiveSec，该单元上次执行后，等多少时间再次执行
OnUnitInactiveSec，定时器上次关闭后多少时间，再次执行
OnCalendar，基于绝对时间，而不是相对时间执行
AccuracySec，如果因为各种原因，任务必须推迟执行，推迟的最大秒数，默认是60秒

3. 添加 service

`1`	`vim /etc/systemd/system/quick-clear.service`

[Unit]
Description=clear every week
Conflicts= quick-clear.timer

[Service]
ExecStart=/root/scripts/quick-clear.sh

4. 管理定时任务

加载配置

`1`	`systemctl daemon-reload`

启动定时任务

`1`	`systemctl start quick-clear.timer`

查看任务状态

`1`	`systemctl status quick-clear.timer`

开机自启动

`1`	`systemctl enable quick-clear.timer`

查看定时日志

journalctl -u quick-clear.timer -f

-- Logs begin at Wed 2022-03-30 12:30:27 CST. --
May 26 14:30:17 node3 systemd[1]: Started clear every week.

查看任务执行日志

`1`	`journalctl -u quick-clear.service -f`

查看全部定时任务

systemctl list-timers

NEXT                        LEFT          LAST                        PASSED       UNIT                         ACTIVATES                     
Thu 2022-05-26 15:54:35 CST 1h 23min left Thu 2022-05-26 03:42:34 CST 10h ago      ua-messaging.timer           ua-messaging.service          
Thu 2022-05-26 17:58:00 CST 3h 27min left Wed 2022-05-25 17:58:00 CST 20h ago      systemd-tmpfiles-clean.timer systemd-tmpfiles-clean.service
Thu 2022-05-26 19:56:45 CST 5h 26min left Thu 2022-05-26 11:45:53 CST 2h 44min ago fwupd-refresh.timer          fwupd-refresh.service         
Fri 2022-05-27 00:00:00 CST 9h left       Thu 2022-05-26 00:00:00 CST 14h ago      logrotate.timer              logrotate.service             
Fri 2022-05-27 00:00:00 CST 9h left       Thu 2022-05-26 00:00:00 CST 14h ago      man-db.timer                 man-db.service                
Fri 2022-05-27 00:00:37 CST 9h left       Thu 2022-05-26 14:30:07 CST 35s ago      motd-news.timer              motd-news.service             
Fri 2022-05-27 04:38:51 CST 14h left      Thu 2022-05-26 14:29:47 CST 55s ago      apt-daily.timer              apt-daily.service             
Fri 2022-05-27 06:09:35 CST 15h left      Thu 2022-05-26 06:37:25 CST 7h ago       apt-daily-upgrade.timer      apt-daily-upgrade.service     
Sun 2022-05-29 03:10:09 CST 2 days left   Sun 2022-05-22 03:10:55 CST 4 days ago   e2scrub_all.timer            e2scrub_all.service           
Mon 2022-05-30 00:00:00 CST 3 days left   Mon 2022-05-23 00:00:00 CST 3 days ago   fstrim.timer                 fstrim.service                
Wed 2022-06-01 18:53:47 CST 6 days left   n/a                         n/a          quick-clear.timer            quick-clear.service