postfwd - docker support

postfwd docker support

To run postfwd in a docker container you should use at least version 1.39 of postfwd. There are pre-built images postfwd/postfwd:stable or postfwd/postfwd:devel available at from DockerHub. Alternatively you can download the postfwd distibution and build the image by yourself.

Quicknav

Using a pre-built image
- docker
- docker-compose
Building your own image
- get postfwd docker files
- build the image
Configure the container

Using a pre-built image

a.) docker

Get the image:
```
docker pull postfwd/postfwd:stable
```

Execute a container based on that image:

docker run -it -p 127.0.0.1:10040:10040 postfwd/postfwd:stable

b.) docker-compose

Create docker-compose.yml:

version: '2'

services:
  postfwd:
    image: postfwd/postfwd:stable
    restart: always
    ports:
      # Modify interface and port below if required!
      - 127.0.0.1:10040:10040

Execute the container:
```
docker-compose up
```

Building your own image

Get the postfwd docker files

The Dockerfile that was used to build the images at DockerHub can be found within the subfolder docker/ of the postfwd distribution. You can get it from:

GitHub:

git clone https://github.com/postfwd/postfwd --branch master --single-branch postfwd

postfwd.org:

wget https://postfwd.org/postfwd-latest.tar.gz && gzip -dc postfwd-latest.tar.gz | tar -xf - && rm postfwd-latest.tar.gz

Build the image

Edit docker/Dockerfile-autobuild and build the image:

docker build --no-cache --pull -f docker/Dockerfile-autobuild -t postfwd:mybuild .

Execute a container based on that image:
```
docker run -it postfwd:mybuild
```

Configure the container

For reasonable operation you should configure postfwd. First create your own ruleset. Please look at the manpage or postfwd.org for more information on this topic.

Save your ruleset to a file on the docker host - it will be further refered as:
```
/path/to/ruleset
```

Now specify the program options via the container environment. The following settings are available:

# use 'postfwd1' or 'postfwd2' to switch between versions
# go to http://postfwd.org/versions.html for more info
PROG=postfwd1
# port for postfwd
PORT=10040
# configuration file
CONF=postfwd.cf
# request cache in seconds. use '0' to disable
CACHE=60
# additional arguments, see postfwd -h or man page for more
EXTRA=--no_parent_dns_cache --noidlestats --summary=600

a.) docker

Run postfwd2 instead of postfwd1:

docker run -v /path/to/ruleset:/etc/postfwd/postfwd.cf:ro -e PROG=postfwd2 -it postfwd:stable

Disable request-cache, enable verbose logging:

docker run -v /path/to/ruleset:/etc/postfwd/postfwd.cf:ro -p 127.0.0.1:10040:10040 -e CACHE=0 -e EXTRA="-v" -it postfwd:stable

b.) docker-compose

Run postfwd2 instead of postfwd1, disable cache, enable verbose logging via docker-compose.yml:

#
# docker-compose.yml
#

version: '2' 

services:

  postfwd:
    image: postfwd/postfwd:stable
    environment:
      - PROG=postfwd2
      - CACHE=0
      - EXTRA=-vv --no_parent_dns_cache --noidlestats --summary=600
    restart: always
    ports:
      - 127.0.0.1:10040:10040
    volumes:
      - /path/to/ruleset:/etc/postfwd/postfwd.cf:ro