Docker Cookbook

48 | Chapter 2: Image Creation and Sharing

---

Discussion
Properly tagging an image is an important part of sharing it on Docker Hub (see
Recipe 2.9
) or using a private registry (see 
Recipe 2.11
). The 
docker tag
help infor‐
mation is pretty succint but shows the proper naming convention, which references
the proper namespace, be it local, on Docker Hub, or on a private registry:
$ docker tag -h
Usage: docker tag [OPTIONS] IMAGE[:TAG] [REGISTRYHOST/][USERNAME/]NAME[:TAG]
Tag an image into a repository
-f, --force=false Force
2.7 Migrating from Vagrant to Docker with the Docker
Provider
Problem
You have been using 
Vagrant
for your testing and development work and would like
to reuse some of your Vagrantfiles to work with Docker.
Solution
Use the Vagrant Docker 
provider
. You can keep writing Vagrant files to bring up new
containers and develop your Dockerfiles.
Here is an example Vagrantfile that uses the Docker provider:
# -*- mode: ruby -*-
# vi: set ft=ruby :
VAGRANTFILE_API_VERSION
=
"2"
Vagrant
.
configure
(
VAGRANTFILE_API_VERSION
)
do
|
config
|
config
.
vm
.
provider
"docker"
do
|
d
|
d
.
build_dir
=
"."
end
config
.
vm
.
network
"forwarded_port"
,
guest
:
5000
,
host
:
5000
end
The 
build_dir
option looks for a Dockerfile in the same directory as the Vagrantfile.
Vagrant then issues a 
docker build
in turn, and starts the container: