Dockerfile example alpine with cron enabled

[FloCola]

quite handy, have it running on a Synology NAS. Should be running almost anywhere.

Preconfig:

• Download script, save it accessible for the container.
• Script: Change first line to '#!/bin/ash'
• Script: Preconfigure Script-Parameters, or add script parameters to cronjob.
• Dockerfile: Change echo for cronjobs to your needs. See example.
• Mount Container Folder with scripts to '/srv'

# Dockerfile to create image with cron services
FROM alpine:latest

#Configure
RUN apk add --no-cache curl
RUN apk add --no-cache bind-tools
RUN apk add --no-cache jq

#Cronjobs
RUN echo '*/5     *       *       *       *       /bin/ash /srv/hetzner-dyndns_alpine.sh >> /srv/hetzner-dyndns.log' >> /root/crontab.conf

# Add the cron job
RUN crontab /root/crontab.conf

# Run the command on container startup
CMD [ "/usr/sbin/crond", "-f", "-d8" ]

[kladderadeng]

Awesome @FloCola! That helped me a lot :-)

[thcrt]

It's worth noting that installing bind-tools should no longer be necessary, as #35 uses an HTTP API to get the host's IP instead of using dig or nslookup.

It could be a good idea to automate Docker builds to GHCR.