Docker-Registry

Create the configuration

The Docker Registry comes with a sample configuration file, config_sample.yml. Copy this to config.yml to provide a basic configuration:

cp config/config_sample.yml config/config.yml

Configuration flavors

Docker Registry can run in several flavors. This enables you to run it in development mode, production mode or your own predefined mode.

In the config yaml file, you'll see a few sample flavors:

1. common: used by all other flavors as base settings
2. dev: used for development
3. prod: used for production
4. test: used by unit tests
5. openstack: to integrate with openstack

You can define your own flavors by adding a new top-level yaml key.

You can specify which flavor to run by setting SETTINGS_FLAVOR in your environment: export SETTINGS_FLAVOR=dev

The default environment is dev.

NOTE: it's possible to load environment variables from the config file with a simple syntax: _env:VARIABLENAME. Check this syntax in action in the example below...

Example config

common:
    loglevel: info

prod:
    loglevel: warn
    storage: s3
    s3_access_key: _env:AWS_S3_ACCESS_KEY
    s3_secret_key: _env:AWS_S3_SECRET_KEY
    s3_bucket: _env:AWS_S3_BUCKET
    storage_path: /srv/docker
    smtp_host: localhost
    from_addr: [email protected]
    to_addr: [email protected]

dev:
    loglevel: debug
    storage: local
    storage_path: /home/myself/docker

test:
    storage: local
    storage_path: /tmp/tmpdockertmp

Location of the config file

DOCKER_REGISTRY_CONFIG

Specify the config file to be used by setting DOCKER_REGISTRY_CONFIG in your environment: export DOCKER_REGISTRY_CONFIG=config.yml

The default location of the config file is config.yml, located in the config subdirectory. If DOCKER_REGISTRY_CONFIG is a relative path, that path is expanded relative to the config subdirectory.

It is possible to mount the configuration file into the docker image

sudo docker run -p 5000:5000 -v /home/user/registry-conf:/registry-conf -e DOCKER_REGISTRY_CONFIG=/registry-conf/config.yml

Available configuration options

General options

1. secret_key: 64 character string, this key should be unique and secret. It is used by the Registry to sign secret things. If you leave this blank, the Registry will generate a random string.
2. loglevel: string, level of debugging. Any of python's logging module levels: debug, info, warn, error or critical

Authentication options

1. standalone: boolean, run the server in stand-alone mode. This means that the Index service on index.docker.io will not be used for anything. This implies disable_token_auth.

2. index_endpoint: string, configures the hostname of the Index endpoint. This is used to verify passwords of users that log in. It defaults to https://index.docker.io. You should probably leave this to its default.

3. disable_token_auth: boolean, disable checking of tokens with the Docker index. You should provide your own method of authentication (such as Basic auth).

S3 options

These options configure your S3 storage. These are used when storage is set to s3.

1. s3_access_key: string, S3 access key
2. s3_secret_key: string, S3 secret key
3. s3_bucket: string, S3 bucket name
4. s3_encrypt: boolean, if true, the container will be encrypted on the server-side by S3 and will be stored in an encrypted form while at rest in S3.
5. s3_secure: boolean, true for HTTPS to S3
6. boto_bucket: string, the bucket name
7. storage_path: string, the sub "folder" where image data will be stored.

Elliptics options

These options configure your Elliptics storage. These are used when storage is set to elliptics.

1. elliptics_nodes: Elliptics remotes
2. elliptics_wait_timeout: time to wait for the operation complete
3. elliptics_check_timeout: timeout for pinging node
4. elliptics_io_thread_num: number of IO threads in processing pool
5. elliptics_net_thread_num: number of threads in network processing pool
6. elliptics_nonblocking_io_thread_num: number of IO threads in processing pool dedicated to nonblocking ops
7. elliptics_groups: Elliptics groups registry should use
8. elliptics_verbosity: Elliptics logger verbosity (0...4)
9. elliptics_logfile: path to Elliptics logfile (default: dev/stderr)

Example:

dev:
  storage: elliptics
  elliptics_nodes:
      elliptics-host1: 1025
      elliptics-host2: 1025
      ...
      hostN: port
  elliptics_wait_timeout: 60
  elliptics_check_timeout: 60
  elliptics_io_thread_num: 2
  elliptics_net_thread_num: 2
  elliptics_nonblocking_io_thread_num: 2
  elliptics_groups: [1, 2, 3]
  elliptics_verbosity: 4
  elliptics_logfile: "/tmp/logfile.log"
  elliptics_loglevel: debug

Email options

Settings these options makes the Registry send an email on each code Exception:

1. email_exceptions:
2. smtp_host: hostname to connect to using SMTP
3. smtp_port: port number to connect to using SMTP
4. smtp_login: username to use when connecting to authenticated SMTP
5. smtp_password: password to use when connecting to authenticated SMTP
6. smtp_secure: boolean, true for TLS to using SMTP. this could be a path to the TLS key file for client authentication.
7. from_addr: email address to use when sending email
8. to_addr: email address to send exceptions to

Example:

test:
    email_exceptions:
        smtp_host: localhost

Performance on prod

It's possible to add an LRU cache to access small files. In this case you need to spawn a redis-server configured in LRU mode. The config file "config_sample.yml" shows an example to enable the LRU cache using the config directive cache_lru.

Once this feature is enabled, all small files (tags, meta-data) will be cached in Redis. When using a remote storage backend (like Amazon S3), it will speeds things up dramatically since it will reduce roundtrips to S3.

Storage options

storage: can be one of:

1. local: store images on local storage
2. storage_path local path to the image store
3. s3: store images on S3
4. storage_path is a subdir in your S3 bucker
5. remember to set all s3_* options (see above)
6. glance: store images on Glance (OpenStack)
7. storage_alternate: storage engine to use when Glance storage fails, e.g. local
8. If you use storage_alternate local, remeber to set storage_path
9. elliptics: store images in Elliptics key-value storage

Persist local storage

If you use any type of local store along with a registry running within a docker remember to use a data volume for the storage_path. Please read the documentation for data volumes for more information.

Example:

docker run -p 5000 -v /tmp/registry:/tmp/registry registry

Privileged access

Privileged access allows you to make direct requests to the registry by using an RSA key pair. The privileged_key config entry, if set, must indicate a path to a file containing the public key. If it is not set, privileged access is disabled.

Generating keys with openssl

You will need to install the python-rsa package (pip install rsa) in addition to using openssl. Generating the public key using openssl will lead to producing a key in a format not supported by the RSA library the registry is using.

Generate private key:

openssl genrsa  -out private.pem 2048

Associated public key :

pyrsa-priv2pub -i private.pem -o public.pem

Run the Registry

The fast way:

docker run -p 5000:5000 registry

NOTE: The container will try to allocate the port 5000. If the port is already taken, find out which container is already using it by running "docker ps"

The old way:

On Ubuntu

Install the system requirements for building a Python library:

sudo apt-get install build-essential python-dev libevent-dev python-pip libssl-dev liblzma-dev

Then install the Registry app:

sudo pip install -r requirements.txt

On Red Hat-based systems:

sudo yum install python-devel libevent-devel python-pip openssl-devel

NOTE: On RHEL and CentOS you will need the EPEL repostitories enabled. Fedora should not require the additional repositories.

Then install the Registry app:

sudo python-pip install -r requirements.txt

Run it

gunicorn --access-logfile - --debug -k gevent -b 0.0.0.0:5000 -w 1 wsgi:application

How do I setup user accounts?

The first time someone tries to push to your registry, it will prompt them for a username, password, and email.

What about a Production environment?

The recommended setting to run the Registry in a prod environment is gunicorn behind a nginx server which supports chunked transfer-encoding (nginx >= 1.3.9).

You could use for instance supervisord to spawn the registry with 8 workers using this command:

gunicorn -k gevent --max-requests 100 --graceful-timeout 3600 -t 3600 -b localhost:5000 -w 8 wsgi:application

Note that when using multiple workers, the secret_key for the Flask session must be set explicitly in config.yml. Otherwise each worker will use its own random secret key, leading to unpredictable behavior.

nginx

Here is an nginx configuration file example.

And you might want to add Basic auth on Nginx to protect it (if you're not using it on your local network):

Apache

Enable mod_proxy using a2enmod proxy_http, then use this snippet forward requests to the Docker Registry:

  ProxyPreserveHost  On
  ProxyRequests      Off
  ProxyPass          /  http://localhost:5000/
  ProxyPassReverse   /  http://localhost:5000/

dotCloud

The central Registry runs on the dotCloud platform:

cd docker-registry/
dotcloud create myregistry
dotcloud push

Run tests

If you want to submit a pull request, please run the unit tests using tox before submitting anything to the repos:

pip install tox
cd docker-registry/
tox