Using cron tasks in Alpine Linux

     This article briefly explains how to enable scheduled tasks in Alpine Linux.

To upgrade to a new stable release or edge

$ apk upgrade --available

optimized toolbox

$ apk add openrc --no-cache

manages the services

$ apk add busybox-initscripts

Start service crond and add it to runlevel

$ rc-service crond start && rc-update add crond
## OR ##
# $ /etc/init.d/crond start
## OR ##
# $ service crond [start|stop|status|restart]

See crond is running

$ rc-service -l | grep crond 
crond

New task1 your scripts file. Note: The script must not have a file suffix

$ vi /etc/periodic/15min/task1
#!/bin/sh
echo `data` >>/tmp/log.txt

Authorized

$ chmod 777  /etc/periodic/15min/task1

To check whether your scripts are likely to run

$ run-parts --test /etc/periodic/15min

Append schedule tasks, at every minute

$ crontab -e
*/1     *       *       *       *       run-parts /etc/periodic/15min

View all schedule tasks

$  crontab -l
# do daily/weekly/monthly maintenance
# min   hour    day     month   weekday command
*/15    *       *       *       *       run-parts /etc/periodic/15min
0       *       *       *       *       run-parts /etc/periodic/hourly
0       2       *       *       *       run-parts /etc/periodic/daily
0       3       *       *       6       run-parts /etc/periodic/weekly
0       5       1       *       *       run-parts /etc/periodic/monthly
*/1     *       *       *       *       run-parts /etc/periodic/15min

View root user schedule tasks

$  cat /etc/crontabs/root

View run log

$  watch cat /tmp/log.txt

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