Docker Registry Proxy Cache

This vagrant runs a Docker registry proxy cache for local development uses. So long as you don't destroy the vagrant, the cache will continue to persist.

Requirements

• Vagrant
• vagrant-hostmanager plugin

Usage

Simply use vagrant up to bring the vagrant up. When you no longer need it running, use vagrant suspend or vagrant halt to suspend to disk/shut down the vagrant without losing data. Using vagrant destroy will destroy the cache.

With the vagrant running, then configure your docker daemon to use it as a registry mirror. Configuring your docker daemon to use the mirror is out of scope, but here is an example using docker-machine:

docker-machine create -d virtualbox --virtualbox-host-dns-resolver --engine-registry-mirror http://registry.local default

Use of --virtualbox-host-dns-resolver is required so the docker-machine can resolve the registry mirror name from within the VM

Benchmark

This is a simple test using time, take it for what its worth

Before:

$ time docker pull registry
Using default tag: latest
latest: Pulling from library/registry
...
Status: Downloaded newer image for registry:latest

real	0m57.389s
user	0m0.267s
sys	0m0.075s

After:

$ time docker pull registry
Using default tag: latest
latest: Pulling from library/registry
...
Status: Downloaded newer image for registry:latest

real	0m24.382s
user	0m0.256s
sys	0m0.062s

Acknowledgements

Inspired by How to Set Up a Registry Proxy Cache with Docker Open Source Registry blog post from Docker.