Dockerfile

# dnsmasq in a Docker container
#
# This Dockerfile creates an image for the amd64 architecture.
#
# <https://github.com/outlyer-net/docker-dnsmasq-multiarch>
#
# Note previous versions of this Dockerfile used a more hacky way to
#  build multiplatform images, but now that buildx is readily avaible
#  things are much simpler

# Stage 0: Preparations. To be run on the build host
FROM alpine:latest AS buildstage

# This script will install the latest version for the current architecture
# Note it requires bash AND the automatic user-agent detection fails
#  on Alpine's wget
# It will be saved as /webproc
RUN apk add bash curl \
    && curl https://i.jpillora.com/webproc | bash

# Stage 1: The actual produced image
FROM alpine:latest

LABEL maintainer="Toni Corvera <outlyer@gmail.com>"

# import webproc binary from previous stage
COPY --from=0 /webproc /usr/local/bin/

# fetch dnsmasq
RUN apk --no-cache add dnsmasq

# configure dnsmasq
# /etc/default/dnsmasq doesn't exist, XXX: stale config from Debian?
#RUN echo -e "ENABLED=1\nIGNORE_RESOLVCONF=yes" > /etc/default/dnsmasq
COPY dnsmasq.conf /etc/dnsmasq.conf

# The dhcp.leases files is put here, may want to mount as tmpfs
# XXX: should this be preserved?
VOLUME [ "/var/lib/misc" ]

# Ports:
#  80: Web interface
#  67: DHCP
#  53: DNS: dns on udp, dns transfers on tcp
EXPOSE 80/tcp 67/udp 53/tcp 53/udp

# run!
ENTRYPOINT ["webproc","--port","80","--configuration-file","/etc/dnsmasq.conf","--","dnsmasq","--no-daemon"]

HEALTHCHECK --interval=30s \
	--timeout=30s \
	--start-period=10s \
	--retries=3 \
	CMD [ "pidof", "dnsmasq" ]