ymajik/apt-cacher-ng:latest

• Introduction
• Getting started
  • Installation
  • Quickstart
  • Command-line arguments
  • Persistence
  • Usage
  • Logs
• Maintenance
  • Cache expiry
  • Upgrading
  • Shell Access

Introduction

Dockerfile to create a Docker container image for Apt-Cacher NG.

Apt-Cacher NG is a caching proxy, specialized for package files from Linux distributors, primarily for Debian (and Debian based) distributions but not limited to those.

Getting started

Installation

Automated builds of the image are available on Dockerhub and is the recommended method of installation.

docker pull ymajik/apt-cacher-ng:latest

Alternatively you can build the image yourself.

docker build -t ymajik/apt-cacher-ng github.com/ymajik/docker-apt-cacher-ng

Quickstart

Start Apt-Cacher NG using:

docker run --name apt-cacher-ng -d --restart=always \
  --publish 3142:3142 \
  --volume /srv/docker/apt-cacher-ng:/var/cache/apt-cacher-ng \
  ymajik/apt-cacher-ng:latest

Alternatively, you can use the sample docker-compose.yml file to start the container using Docker Compose

Command-line arguments

You can customize the launch command of Apt-Cacher NG server by specifying arguments to apt-cacher-ng on the docker run command. For example the following command prints the help menu of apt-cacher-ng command:

docker run --name apt-cacher-ng -it --rm \
  --publish 3142:3142 \
  --volume /srv/docker/apt-cacher-ng:/var/cache/apt-cacher-ng \
  ymajik/apt-cacher-ng:latest -h

Persistence

For the cache to preserve its state across container shutdown and startup you should mount a volume at /var/cache/apt-cacher-ng.

The Quickstart command already mounts a volume for persistence.

SELinux users should update the security context of the host mountpoint so that it plays nicely with Docker:

mkdir -p /srv/docker/apt-cacher-ng
chcon -Rt svirt_sandbox_file_t /srv/docker/apt-cacher-ng

Usage

To start using Apt-Cacher NG on your Debian (and Debian based) host, create the configuration file /etc/apt/apt.conf.d/01proxy with the following content:

Acquire::HTTP::Proxy "http://172.17.0.1:3142";
Acquire::HTTPS::Proxy "false";

Similarly, to use Apt-Cacher NG in you Docker containers add the following line to your Dockerfile before any apt-get commands.

RUN echo 'Acquire::HTTP::Proxy "http://172.17.0.1:3142";' >> /etc/apt/apt.conf.d/01proxy \
 && echo 'Acquire::HTTPS::Proxy "false";' >> /etc/apt/apt.conf.d/01proxy

Logs

To access the Apt-Cacher NG logs, located at /var/log/apt-cacher-ng, you can use docker exec. For example, if you want to tail the logs:

docker exec -it apt-cacher-ng tail -f /var/log/apt-cacher-ng/apt-cacher.log

Maintenance

Cache expiry

Using the Command-line arguments feature, you can specify the -e argument to initiate Apt-Cacher NG's cache expiry maintenance task.

docker run --name apt-cacher-ng -it --rm \
  --publish 3142:3142 \
  --volume /srv/docker/apt-cacher-ng:/var/cache/apt-cacher-ng \
  ymajik/apt-cacher-ng:latest -e

The same can also be achieved on a running instance by visiting the url http://localhost:3142/acng-report.html in the web browser and selecting the Start Scan and/or Expiration option.

Upgrading

To upgrade to newer releases:

1. Download the updated Docker image:

docker pull ymajik/apt-cacher-ng:latest

2. Stop the currently running image:

docker stop apt-cacher-ng

3. Remove the stopped container

docker rm -v apt-cacher-ng

4. Start the updated image

docker run -name apt-cacher-ng -d \
  [OPTIONS] \
  ymajik/apt-cacher-ng:latest

Shell Access

For debugging and maintenance purposes you may want access the containers shell. If you are using Docker version 1.3.0 or higher you can access a running containers shell by starting bash using docker exec:

docker exec -it apt-cacher-ng bash