Varnish Docker image

Varnish docker image with support for dynamic backends, Rancher DNS, auto-configure and reload.

This image is generic, thus you can obviously re-use it within your non-related EEA projects.

• Alpine 3.19
• Varnish 7.6.1
• Expose 80, 8443

Supported tags and respective Dockerfile links

• :7 Dockerfile (Alpine 3.19, Varnish 7.6.1)

Stable and immutable tags

• :4.1-6.5 Dockerfile - Varnish: 4.1.11 Release: 6.5
• :7.2-1.0 Dockerfile - Varnish: 7.2 Release: 1.0
• :7.4-1.1 Dockerfile - Varnish: 7.4.2 Release: 1.1
• :7.5-1.0 Dockerfile - Varnish: 7.5.0 Release: 1.0
• :7.6-1.0 Dockerfile - Varnish: 7.6.1 Release: 1.0

See older versions

Changes

• CHANGELOG.md

Base docker image

• hub.docker.com

Source code

• github.com

Installation

1. Install Docker.

Variables

• VARNISH_HTTP_PORT - varnish port
• VARNISH_HTTPS_PORT - varnish ssl port
• VARNISH_SIZE - varnish cache size
• AUTOKILL_CRON - Varnish re-create crontab, will force a recreation of the container. Uses UTC time, format is linux crontab - for example - 0 2 * * * is 02:00 UTC each day"
• VARNISH_CFG_CONTENT - Multiline variable that will be written in the default.vcl file

Usage

Using VARNISH_CFG_CONTENT

See docker-compose.yml.

Extend the image with a custom varnish.vcl file

The default.vcl file provided with this image is bare and only contains the marker to specify the VCL version. If you plan on using a more elaborate base configuration in your container and you want it shipped with your image, you can extend the image in a Dockerfile, like this:

FROM eeacms/varnish
COPY varnish.vcl /etc/varnish/default.vcl

and then run

$ docker build -t varnish-custom /path/to/Dockerfile

How to add docker environment variables in varnish.vcl

1. Choose relevant variable name, starting with VARNISH_ - eg. VARNISH_EXAMPLE

2. Add default value in Dockerfile

   ENV VARNISH_EXAMPLE="GET"

3. Add variable in <> in varnish.vcl

   set req.http.X-Varnish-Routed = "<VARNISH_EXAMPLE>";

4. Add description in Readme.md

Using a read-only volume for the vcl template files - /varnish-config

The volume /varnish-config will be used to store the read only vcl template configuration files. They will be copied with the same structure to /etc/varnish, where the variable substitution will be done.

Rancher integration

Use dynamic.director to integrate varnish in rancher DNS - if a backend containers are changed, it knows to get the latest list of IPs automatically.

  new cluster = dynamic.director(port = "<VARNISH_BACKEND_PORT>", ttl = <VARNISH_DNS_TTL>);

Example:

You can use plone-varnish as an example of usage.

Upgrade

$ docker pull eeacms/varnish

Copyright and license

The Initial Owner of the Original Code is European Environment Agency (EEA). All Rights Reserved.

The Original Code is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.

Funding

European Environment Agency (EU)