How to Build a Dovecot Docker Image

Another image I build for myself because I don’t want to use 3rd party non-official images from DockerHub. They could do anything with my precious emails. Also, building a docker image for dovecot is pretty straightforward.

The Dockerfile just has to install the Dovecot packages, expose the imap ports and start Dovecot:

Dockerfile

FROM alpine:3.16

# You might not need the pigeonhole (sieve) plugin or the rspamd package
RUN apk update && \
    apk add dovecot dovecot-ldap dovecot-lmtpd dovecot-pigeonhole-plugin rspamd-client && \
    rm -rf /var/cache/apk/*
COPY config/conf.d/10-logging.conf /etc/dovecot/conf.d/10-logging.conf

EXPOSE 24/tcp
EXPOSE 143/tcp
EXPOSE 993/tcp

CMD /usr/sbin/dovecot -F

Dovecot will start in foreground, keeping the container alive. We want to check the logs via docker logs so we redirect all dovecot log output to stderr:

config/conf.d/10-logging.conf

log_path = /dev/stderr

The Dockerfile will copy that config file to the image.

Start the build like this:

docker build -t dovecot:2.3.19.1-r0-2 .

Done. Again, you can pick up my Dovecot image on DockerHub. But I guess if you read this article, you want to build your own image?

Also, check out my Postfix image.