distribution/docs/configuration.md

title	description	keywords
Configuring a registry	Explains how to configure a registry	registry, on-prem, images, tags, repository, distribution, configuration

The Registry configuration is based on a YAML file, detailed below. While it comes with sane default values out of the box, you should review it exhaustively before moving your systems to production.

Override specific configuration options

In a typical setup where you run your Registry from the official image, you can specify a configuration variable from the environment by passing -e arguments to your docker run stanza or from within a Dockerfile using the ENV instruction.

To override a configuration option, create an environment variable named REGISTRY_variable where variable is the name of the configuration option and the _ (underscore) represents indention levels. For example, you can configure the rootdirectory of the filesystem storage backend:

storage:
  filesystem:
    rootdirectory: /var/lib/registry

To override this value, set an environment variable like this:

REGISTRY_STORAGE_FILESYSTEM_ROOTDIRECTORY=/somewhere

This variable overrides the /var/lib/registry value to the /somewhere directory.

Note

: Create a base configuration file with environment variables that can be configured to tweak individual values. Overriding configuration sections with environment variables is not recommended.

Overriding the entire configuration file

If the default configuration is not a sound basis for your usage, or if you are having issues overriding keys from the environment, you can specify an alternate YAML configuration file by mounting it as a volume in the container.

Typically, create a new configuration file from scratch,named config.yml, then specify it in the docker run command:

$ docker run -d -p 5000:5000 --restart=always --name registry \
             -v `pwd`/config.yml:/etc/docker/registry/config.yml \
             registry:2

Use this example YAML file as a starting point.

List of configuration options

These are all configuration options for the registry. Some options in the list are mutually exclusive. Read the detailed reference information about each option before finalizing your configuration.

version: 0.1
log:
  accesslog:
    disabled: true
  level: debug
  formatter: text
  fields:
    service: registry
    environment: staging
  hooks:
    - type: mail
      disabled: true
      levels:
        - panic
      options:
        smtp:
          addr: mail.example.com:25
          username: mailuser
          password: password
          insecure: true
        from: sender@example.com
        to:
          - errors@example.com
loglevel: debug # deprecated: use "log"
storage:
  filesystem:
    rootdirectory: /var/lib/registry
    maxthreads: 100
  azure:
    accountname: accountname
    accountkey: base64encodedaccountkey
    container: containername
  gcs:
    bucket: bucketname
    keyfile: /path/to/keyfile
    rootdirectory: /gcs/object/name/prefix
    chunksize: 5242880
  s3:
    accesskey: awsaccesskey
    secretkey: awssecretkey
    region: us-west-1
    regionendpoint: http://myobjects.local
    bucket: bucketname
    encrypt: true
    keyid: mykeyid
    secure: true
    v4auth: true
    chunksize: 5242880
    multipartcopychunksize: 33554432
    multipartcopymaxconcurrency: 100
    multipartcopythresholdsize: 33554432
    rootdirectory: /s3/object/name/prefix
  swift:
    username: username
    password: password
    authurl: https://storage.myprovider.com/auth/v1.0 or https://storage.myprovider.com/v2.0 or https://storage.myprovider.com/v3/auth
    tenant: tenantname
    tenantid: tenantid
    domain: domain name for Openstack Identity v3 API
    domainid: domain id for Openstack Identity v3 API
    insecureskipverify: true
    region: fr
    container: containername
    rootdirectory: /swift/object/name/prefix
  oss:
    accesskeyid: accesskeyid
    accesskeysecret: accesskeysecret
    region: OSS region name
    endpoint: optional endpoints
    internal: optional internal endpoint
    bucket: OSS bucket
    encrypt: optional data encryption setting
    secure: optional ssl setting
    chunksize: optional size valye
    rootdirectory: optional root directory
  inmemory:  # This driver takes no parameters
  delete:
    enabled: false
  redirect:
    disable: false
  cache:
    blobdescriptor: redis
  maintenance:
    uploadpurging:
      enabled: true
      age: 168h
      interval: 24h
      dryrun: false
    readonly:
      enabled: false
auth:
  silly:
    realm: silly-realm
    service: silly-service
  token:
    realm: token-realm
    service: token-service
    issuer: registry-token-issuer
    rootcertbundle: /root/certs/bundle
  htpasswd:
    realm: basic-realm
    path: /path/to/htpasswd
middleware:
  registry:
    - name: ARegistryMiddleware
      options:
        foo: bar
  repository:
    - name: ARepositoryMiddleware
      options:
        foo: bar
  storage:
    - name: cloudfront
      options:
        baseurl: https://my.cloudfronted.domain.com/
        privatekey: /path/to/pem
        keypairid: cloudfrontkeypairid
        duration: 3000s
        ipfilteredby: awsregion
        awsregion: us-east-1, use-east-2
        updatefrenquency: 12h
        iprangesurl: https://ip-ranges.amazonaws.com/ip-ranges.json
  storage:
    - name: redirect
      options:
        baseurl: https://example.com/
reporting:
  bugsnag:
    apikey: bugsnagapikey
    releasestage: bugsnagreleasestage
    endpoint: bugsnagendpoint
  newrelic:
    licensekey: newreliclicensekey
    name: newrelicname
    verbose: true
http:
  addr: localhost:5000
  prefix: /my/nested/registry/
  host: https://myregistryaddress.org:5000
  secret: asecretforlocaldevelopment
  relativeurls: false
  tls:
    certificate: /path/to/x509/public
    key: /path/to/x509/private
    clientcas:
      - /path/to/ca.pem
      - /path/to/another/ca.pem
    letsencrypt:
      cachefile: /path/to/cache-file
      email: emailused@letsencrypt.com
      hosts: [myregistryaddress.org]
  debug:
    addr: localhost:5001
    prometheus:
      enabled: true
      path: /metrics
  headers:
    X-Content-Type-Options: [nosniff]
  http2:
    disabled: false
notifications:
  events:
    manifestlayers: true
  endpoints:
    - name: alistener
      disabled: false
      url: https://my.listener.com/event
      headers: <http.Header>
      timeout: 1s
      threshold: 10
      backoff: 1s
      ignoredmediatypes:
        - application/octet-stream
      ignore:
        mediatypes:
           - application/octet-stream
        actions:
           - pull
redis:
  addr: localhost:6379
  password: asecret
  db: 0
  dialtimeout: 10ms
  readtimeout: 10ms
  writetimeout: 10ms
  pool:
    maxidle: 16
    maxactive: 64
    idletimeout: 300s
health:
  storagedriver:
    enabled: true
    interval: 10s
    threshold: 3
  file:
    - file: /path/to/checked/file
      interval: 10s
  http:
    - uri: http://server.to.check/must/return/200
      headers:
        Authorization: [Basic QWxhZGRpbjpvcGVuIHNlc2FtZQ==]
      statuscode: 200
      timeout: 3s
      interval: 10s
      threshold: 3
  tcp:
    - addr: redis-server.domain.com:6379
      timeout: 3s
      interval: 10s
      threshold: 3
proxy:
  remoteurl: https://registry-1.docker.io
  username: [username]
  password: [password]
compatibility:
  schema1:
    signingkeyfile: /etc/registry/key.json
validation:
  manifests:
    urls:
      allow:
        - ^https?://([^/]+\.)*example\.com/
      deny:
        - ^https?://www\.example\.com/

In some instances a configuration option is optional but it contains child options marked as required. In these cases, you can omit the parent with all its children. However, if the parent is included, you must also include all the children marked required.

version

version: 0.1

The version option is required. It specifies the configuration's version. It is expected to remain a top-level field, to allow for a consistent version check before parsing the remainder of the configuration file.

log

The log subsection configures the behavior of the logging system. The logging system outputs everything to stdout. You can adjust the granularity and format with this configuration section.

log:
  accesslog:
    disabled: true
  level: debug
  formatter: text
  fields:
    service: registry
    environment: staging

Parameter	Required	Description
level	no	Sets the sensitivity of logging output. Permitted values are error, warn, info, and debug. The default is info.
formatter	no	This selects the format of logging output. The format primarily affects how keyed attributes for a log line are encoded. Options are text, json, and logstash. The default is text.
fields	no	A map of field names to values. These are added to every log line for the context. This is useful for identifying log messages source after being mixed in other systems.

accesslog

accesslog:
  disabled: true

Within log, accesslog configures the behavior of the access logging system. By default, the access logging system outputs to stdout in Combined Log Format. Access logging can be disabled by setting the boolean flag disabled to true.

hooks

hooks:
  - type: mail
    levels:
      - panic
    options:
      smtp:
        addr: smtp.sendhost.com:25
        username: sendername
        password: password
        insecure: true
      from: name@sendhost.com
      to:
        - name@receivehost.com

The hooks subsection configures the logging hooks' behavior. This subsection includes a sequence handler which you can use for sending mail, for example. Refer to loglevel to configure the level of messages printed.

loglevel

DEPRECATED: Please use log instead.

loglevel: debug

Permitted values are error, warn, info and debug. The default is info.

storage

storage:
  filesystem:
    rootdirectory: /var/lib/registry
  azure:
    accountname: accountname
    accountkey: base64encodedaccountkey
    container: containername
  gcs:
    bucket: bucketname
    keyfile: /path/to/keyfile
    rootdirectory: /gcs/object/name/prefix
  s3:
    accesskey: awsaccesskey
    secretkey: awssecretkey
    region: us-west-1
    regionendpoint: http://myobjects.local
    bucket: bucketname
    encrypt: true
    keyid: mykeyid
    secure: true
    v4auth: true
    chunksize: 5242880
    multipartcopychunksize: 33554432
    multipartcopymaxconcurrency: 100
    multipartcopythresholdsize: 33554432
    rootdirectory: /s3/object/name/prefix
  swift:
    username: username
    password: password
    authurl: https://storage.myprovider.com/auth/v1.0 or https://storage.myprovider.com/v2.0 or https://storage.myprovider.com/v3/auth
    tenant: tenantname
    tenantid: tenantid
    domain: domain name for Openstack Identity v3 API
    domainid: domain id for Openstack Identity v3 API
    insecureskipverify: true
    region: fr
    container: containername
    rootdirectory: /swift/object/name/prefix
  oss:
    accesskeyid: accesskeyid
    accesskeysecret: accesskeysecret
    region: OSS region name
    endpoint: optional endpoints
    internal: optional internal endpoint
    bucket: OSS bucket
    encrypt: optional data encryption setting
    secure: optional ssl setting
    chunksize: optional size valye
    rootdirectory: optional root directory
  inmemory:
  delete:
    enabled: false
  cache:
    blobdescriptor: inmemory
  maintenance:
    uploadpurging:
      enabled: true
      age: 168h
      interval: 24h
      dryrun: false
    readonly:
      enabled: false
  redirect:
    disable: false

The storage option is required and defines which storage backend is in use. You must configure exactly one backend. If you configure more, the registry returns an error. You can choose any of these backend storage drivers:

Storage driver	Description
filesystem	Uses the local disk to store registry files. It is ideal for development and may be appropriate for some small-scale production applications. See the driver's reference documentation.
azure	Uses Microsoft Azure Blob Storage. See the driver's reference documentation.
gcs	Uses Google Cloud Storage. See the driver's reference documentation.
s3	Uses Amazon Simple Storage Service (S3) and compatible Storage Services. See the driver's reference documentation.
swift	Uses Openstack Swift object storage. See the driver's reference documentation.
oss	Uses Aliyun OSS for object storage. See the driver's reference documentation.

For testing only, you can use the inmemory storage driver. If you would like to run a registry from volatile memory, use the filesystem driver on a ramdisk.

If you are deploying a registry on Windows, a Windows volume mounted from the host is not recommended. Instead, you can use a S3 or Azure backing data-store. If you do use a Windows volume, the length of the PATH to the mount point must be within the MAX_PATH limits (typically 255 characters), or this error will occur:

mkdir /XXX protocol error and your registry will not function properly.

maintenance

Currently, upload purging and read-only mode are the only maintenance functions available.

uploadpurging

Upload purging is a background process that periodically removes orphaned files from the upload directories of the registry. Upload purging is enabled by default. To configure upload directory purging, the following parameters must be set.

Parameter	Required	Description
enabled	yes	Set to true to enable upload purging. Defaults to true.
age	yes	Upload directories which are older than this age will be deleted.Defaults to 168h (1 week).
interval	yes	The interval between upload directory purging. Defaults to 24h.
dryrun	yes	Set dryrun to true to obtain a summary of what directories will be deleted. Defaults to false.

Note

: age and interval are strings containing a number with optional fraction and a unit suffix. Some examples: 45m, 2h10m, 168h.

readonly

If the readonly section under maintenance has enabled set to true, clients will not be allowed to write to the registry. This mode is useful to temporarily prevent writes to the backend storage so a garbage collection pass can be run. Before running garbage collection, the registry should be restarted with readonly's enabled set to true. After the garbage collection pass finishes, the registry may be restarted again, this time with readonly removed from the configuration (or set to false).

delete

Use the delete structure to enable the deletion of image blobs and manifests by digest. It defaults to false, but it can be enabled by writing the following on the configuration file:

delete:
  enabled: true

cache

Use the cache structure to enable caching of data accessed in the storage backend. Currently, the only available cache provides fast access to layer metadata, which uses the blobdescriptor field if configured.

You can set blobdescriptor field to redis or inmemory. If set to redis,a Redis pool caches layer metadata. If set to inmemory, an in-memory map caches layer metadata.

Note

: Formerly, blobdescriptor was known as layerinfo. While these are equivalent, layerinfo has been deprecated.

redirect

The redirect subsection provides configuration for managing redirects from content backends. For backends that support it, redirecting is enabled by default. In certain deployment scenarios, you may decide to route all data through the Registry, rather than redirecting to the backend. This may be more efficient when using a backend that is not co-located or when a registry instance is aggressively caching.

To disable redirects, add a single flag disable, set to true under the redirect section:

redirect:
  disable: true

auth

auth:
  silly:
    realm: silly-realm
    service: silly-service
  token:
    realm: token-realm
    service: token-service
    issuer: registry-token-issuer
    rootcertbundle: /root/certs/bundle
  htpasswd:
    realm: basic-realm
    path: /path/to/htpasswd

The auth option is optional. Possible auth providers include:

• silly
• token
• htpasswd

You can configure only one authentication provider.

silly

The silly authentication provider is only appropriate for development. It simply checks for the existence of the Authorization header in the HTTP request. It does not check the header's value. If the header does not exist, the silly auth responds with a challenge response, echoing back the realm, service, and scope for which access was denied.

The following values are used to configure the response:

Parameter	Required	Description
realm	yes	The realm in which the registry server authenticates.
service	yes	The service being authenticated.

token

Token-based authentication allows you to decouple the authentication system from the registry. It is an established authentication paradigm with a high degree of security.

Parameter	Required	Description
realm	yes	The realm in which the registry server authenticates.
service	yes	The service being authenticated.
issuer	yes	The name of the token issuer. The issuer inserts this into the token so it must match the value configured for the issuer.
rootcertbundle	yes	The absolute path to the root certificate bundle. This bundle contains the public part of the certificates used to sign authentication tokens.

For more information about Token based authentication configuration, see the specification.

htpasswd

The htpasswd authentication backed allows you to configure basic authentication using an Apache htpasswd file. The only supported password format is bcrypt. Entries with other hash types are ignored. The htpasswd file is loaded once, at startup. If the file is invalid, the registry will display an error and will not start.

Warning

: Only use the htpasswd authentication scheme with TLS configured, since basic authentication sends passwords as part of the HTTP header.

Parameter	Required	Description
realm	yes	The realm in which the registry server authenticates.
path	yes	The path to the htpasswd file to load at startup.

middleware

The middleware structure is optional. Use this option to inject middleware at named hook points. Each middleware must implement the same interface as the object it is wrapping. For instance, a registry middleware must implement the distribution.Namespace interface, while a repository middleware must implement distribution.Repository, and a storage middleware must implement driver.StorageDriver.

This is an example configuration of the cloudfront middleware, a storage middleware:

middleware:
  registry:
    - name: ARegistryMiddleware
      options:
        foo: bar
  repository:
    - name: ARepositoryMiddleware
      options:
        foo: bar
  storage:
    - name: cloudfront
      options:
        baseurl: https://my.cloudfronted.domain.com/
        privatekey: /path/to/pem
        keypairid: cloudfrontkeypairid
        duration: 3000s
        ipfilteredby: awsregion
        awsregion: us-east-1, use-east-2
        updatefrenquency: 12h
        iprangesurl: https://ip-ranges.amazonaws.com/ip-ranges.json

Each middleware entry has name and options entries. The name must correspond to the name under which the middleware registers itself. The options field is a map that details custom configuration required to initialize the middleware. It is treated as a map[string]interface{}. As such, it supports any interesting structures desired, leaving it up to the middleware initialization function to best determine how to handle the specific interpretation of the options.

cloudfront

Parameter	Required	Description
baseurl	yes	The SCHEME://HOST[/PATH] at which Cloudfront is served.
privatekey	yes	The private key for Cloudfront, provided by AWS.
keypairid	yes	The key pair ID provided by AWS.
duration	no	An integer and unit for the duration of the Cloudfront session. Valid time units are ns, us (or µs), ms, s, m, or h. For example, 3000s is valid, but 3000 s is not. If you do not specify a duration or you specify an integer without a time unit, the duration defaults to 20m (20 minutes).
ipfilteredby	no	A string with the following value `none
awsregion	no	A comma separated string of AWS regions, only available when ipfilteredby is awsregion. For example, us-east-1, us-west-2
updatefrenquency	no	The frequency to update AWS IP regions, default: 12h
iprangesurl	no	The URL contains the AWS IP ranges information, default: https://ip-ranges.amazonaws.com/ip-ranges.json
Then value of ipfilteredby:
none: default, do not filter by IP
aws: IP from AWS goes to S3 directly
awsregion: IP from certain AWS regions goes to S3 directly, use together with awsregion

redirect

You can use the redirect storage middleware to specify a custom URL to a location of a proxy for the layer stored by the S3 storage driver.

Parameter	Required	Description
baseurl	yes	SCHEME://HOST at which layers are served. Can also contain port. For example, https://example.com:5443.

reporting

reporting:
  bugsnag:
    apikey: bugsnagapikey
    releasestage: bugsnagreleasestage
    endpoint: bugsnagendpoint
  newrelic:
    licensekey: newreliclicensekey
    name: newrelicname
    verbose: true

The reporting option is optional and configures error and metrics reporting tools. At the moment only two services are supported:

• Bugsnag
• New Relic

A valid configuration may contain both.

bugsnag

Parameter	Required	Description
apikey	yes	The API Key provided by Bugsnag.
releasestage	no	Tracks where the registry is deployed, using a string like production, staging, or development.
endpoint	no	The enterprise Bugsnag endpoint.

newrelic

Parameter	Required	Description
licensekey	yes	License key provided by New Relic.
name	no	New Relic application name.
verbose	no	Set to true to enable New Relic debugging output on stdout.

http

http:
  addr: localhost:5000
  net: tcp
  prefix: /my/nested/registry/
  host: https://myregistryaddress.org:5000
  secret: asecretforlocaldevelopment
  relativeurls: false
  tls:
    certificate: /path/to/x509/public
    key: /path/to/x509/private
    clientcas:
      - /path/to/ca.pem
      - /path/to/another/ca.pem
    letsencrypt:
      cachefile: /path/to/cache-file
      email: emailused@letsencrypt.com
      hosts: [myregistryaddress.org]
  debug:
    addr: localhost:5001
  headers:
    X-Content-Type-Options: [nosniff]
  http2:
    disabled: false

The http option details the configuration for the HTTP server that hosts the registry.

Parameter	Required	Description
addr	yes	The address for which the server should accept connections. The form depends on a network type (see the net option). Use HOST:PORT for TCP and FILE for a UNIX socket.
net	no	The network used to create a listening socket. Known networks are unix and tcp.
prefix	no	If the server does not run at the root path, set this to the value of the prefix. The root path is the section before v2. It requires both preceding and trailing slashes, such as in the example /path/.
host	no	A fully-qualified URL for an externally-reachable address for the registry. If present, it is used when creating generated URLs. Otherwise, these URLs are derived from client requests.
secret	no	A random piece of data used to sign state that may be stored with the client to protect against tampering. For production environments you should generate a random piece of data using a cryptographically secure random generator. If you omit the secret, the registry will automatically generate a secret when it starts. If you are building a cluster of registries behind a load balancer, you MUST ensure the secret is the same for all registries.
relativeurls	no	If true, the registry returns relative URLs in Location headers. The client is responsible for resolving the correct URL. This option is not compatible with Docker 1.7 and earlier.

tls

The tls structure within http is optional. Use this to configure TLS for the server. If you already have a web server running on the same host as the registry, you may prefer to configure TLS on that web server and proxy connections to the registry server.

Parameter	Required	Description
certificate	yes	Absolute path to the x509 certificate file.
key	yes	Absolute path to the x509 private key file.
clientcas	no	An array of absolute paths to x509 CA files.

letsencrypt

The letsencrypt structure within tls is optional. Use this to configure TLS certificates provided by Let's Encrypt.

Note

: When using Let's Encrypt, ensure that the outward-facing address is accessible on port 443. The registry defaults to listening on port 5000. If you run the registry as a container, consider adding the flag -p 443:5000 to the docker run command or using a similar setting in a cloud configuration. You should also set the hosts option to the list of hostnames that are valid for this registry to avoid trying to get certificates for random hostnames due to malicious clients connecting with bogus SNI hostnames.

Parameter	Required	Description
cachefile	yes	Absolute path to a file where the Let's Encrypt agent can cache data.
email	yes	The email address used to register with Let's Encrypt.
hosts	no	The hostnames allowed for Let's Encrypt certificates.

debug

The debug option is optional . Use it to configure a debug server that can be helpful in diagnosing problems. The debug endpoint can be used for monitoring registry metrics and health, as well as profiling. Sensitive information may be available via the debug endpoint. Please be certain that access to the debug endpoint is locked down in a production environment.

The debug section takes a single required addr parameter, which specifies the HOST:PORT on which the debug server should accept connections.

prometheus

The prometheus option defines whether the prometheus metrics is enable, as well as the path to access the metrics.

Parameter	Required	Description
enabled	no	Set true to enable the prometheus server
path	no	The path to access the metrics, /metrics by default

The url to access the metrics is HOST:PORT/path, where HOST:PORT is defined in addr under debug.

headers

The headers option is optional . Use it to specify headers that the HTTP server should include in responses. This can be used for security headers such as Strict-Transport-Security.

The headers option should contain an option for each header to include, where the parameter name is the header's name, and the parameter value a list of the header's payload values.

Including X-Content-Type-Options: [nosniff] is recommended, so that browsers will not interpret content as HTML if they are directed to load a page from the registry. This header is included in the example configuration file.

http2

The http2 structure within http is optional. Use this to control http2 settings for the registry.

Parameter	Required	Description
disabled	no	If true, then http2 support is disabled.

notifications

notifications:
  events:
    manifestlayers: true
  endpoints:
    - name: alistener
      disabled: false
      url: https://my.listener.com/event
      headers: <http.Header>
      timeout: 1s
      threshold: 10
      backoff: 1s
      ignoredmediatypes:
        - application/octet-stream
      ignore:
        mediatypes:
           - application/octet-stream
        actions:
           - pull

The notifications option is optional and currently may contain a single option, endpoints.

endpoints

The endpoints structure contains a list of named services (URLs) that can accept event notifications.

Parameter	Required	Description
name	yes	A human-readable name for the service.
disabled	no	If true, notifications are disabled for the service.
url	yes	The URL to which events should be published.
headers	yes	A list of static headers to add to each request. Each header's name is a key beneath headers, and each value is a list of payloads for that header name. Values must always be lists.
timeout	yes	A value for the HTTP timeout. A positive integer and an optional suffix indicating the unit of time, which may be ns, us, ms, s, m, or h. If you omit the unit of time, ns is used.
threshold	yes	An integer specifying how long to wait before backing off a failure.
backoff	yes	How long the system backs off before retrying after a failure. A positive integer and an optional suffix indicating the unit of time, which may be ns, us, ms, s, m, or h. If you omit the unit of time, ns is used.
ignoredmediatypes	no	A list of target media types to ignore. Events with these target media types are not published to the endpoint.
ignore	no	Events with these mediatypes or actions are not published to the endpoint.

ignore

Parameter	Required	Description
mediatypes	no	A list of target media types to ignore. Events with these target media types are not published to the endpoint.
actions	no	A list of actions to ignore. Events with these actions are not published to the endpoint.

events

The events structure configures the information provided in event notifications.

Parameter	Required	Description
manifestlayers	no	If true, include layer information in manifest events.

redis

redis:
  addr: localhost:6379
  password: asecret
  db: 0
  dialtimeout: 10ms
  readtimeout: 10ms
  writetimeout: 10ms
  pool:
    maxidle: 16
    maxactive: 64
    idletimeout: 300s

Declare parameters for constructing the redis connections. Registry instances may use the Redis instance for several applications. Currently, it caches information about immutable blobs. Most of the redis options control how the registry connects to the redis instance. You can control the pool's behavior with the pool subsection.

You should configure Redis with the allkeys-lru eviction policy, because the registry does not set an expiration value on keys.

Parameter	Required	Description
addr	yes	The address (host and port) of the Redis instance.
password	no	A password used to authenticate to the Redis instance.
db	no	The name of the database to use for each connection.
dialtimeout	no	The timeout for connecting to the Redis instance.
readtimeout	no	The timeout for reading from the Redis instance.
writetimeout	no	The timeout for writing to the Redis instance.

pool

pool:
  maxidle: 16
  maxactive: 64
  idletimeout: 300s

Use these settings to configure the behavior of the Redis connection pool.

Parameter	Required	Description
maxidle	no	The maximum number of idle connections in the pool.
maxactive	no	The maximum number of connections which can be open before blocking a connection request.
idletimeout	no	How long to wait before closing inactive connections.

health

health:
  storagedriver:
    enabled: true
    interval: 10s
    threshold: 3
  file:
    - file: /path/to/checked/file
      interval: 10s
  http:
    - uri: http://server.to.check/must/return/200
      headers:
        Authorization: [Basic QWxhZGRpbjpvcGVuIHNlc2FtZQ==]
      statuscode: 200
      timeout: 3s
      interval: 10s
      threshold: 3
  tcp:
    - addr: redis-server.domain.com:6379
      timeout: 3s
      interval: 10s
      threshold: 3

The health option is optional, and contains preferences for a periodic health check on the storage driver's backend storage, as well as optional periodic checks on local files, HTTP URIs, and/or TCP servers. The results of the health checks are available at the /debug/health endpoint on the debug HTTP server if the debug HTTP server is enabled (see http section).

storagedriver

The storagedriver structure contains options for a health check on the configured storage driver's backend storage. The health check is only active when enabled is set to true.

Parameter	Required	Description
enabled	yes	Set to true to enable storage driver health checks or false to disable them.
interval	no	How long to wait between repetitions of the storage driver health check. A positive integer and an optional suffix indicating the unit of time. The suffix is one of ns, us, ms, s, m, or h. Defaults to 10s if the value is omitted. If you specify a value but omit the suffix, the value is interpreted as a number of nanoseconds.
threshold	no	A positive integer which represents the number of times the check must fail before the state is marked as unhealthy. If not specified, a single failure marks the state as unhealthy.

file

The file structure includes a list of paths to be periodically checked for the
existence of a file. If a file exists at the given path, the health check will fail. You can use this mechanism to bring a registry out of rotation by creating a file.

Parameter	Required	Description
file	yes	The path to check for existence of a file.
interval	no	How long to wait before repeating the check. A positive integer and an optional suffix indicating the unit of time. The suffix is one of ns, us, ms, s, m, or h. Defaults to 10s if the value is omitted. If you specify a value but omit the suffix, the value is interpreted as a number of nanoseconds.

http

The http structure includes a list of HTTP URIs to periodically check with HEAD requests. If a HEAD request does not complete or returns an unexpected status code, the health check will fail.

Parameter	Required	Description
uri	yes	The URI to check.
headers	no	Static headers to add to each request. Each header's name is a key beneath headers, and each value is a list of payloads for that header name. Values must always be lists.
statuscode	no	The expected status code from the HTTP URI. Defaults to 200.
timeout	no	How long to wait before timing out the HTTP request. A positive integer and an optional suffix indicating the unit of time. The suffix is one of ns, us, ms, s, m, or h. If you specify a value but omit the suffix, the value is interpreted as a number of nanoseconds.
interval	no	How long to wait before repeating the check. A positive integer and an optional suffix indicating the unit of time. The suffix is one of ns, us, ms, s, m, or h. Defaults to 10s if the value is omitted. If you specify a value but omit the suffix, the value is interpreted as a number of nanoseconds.
threshold	no	The number of times the check must fail before the state is marked as unhealthy. If this field is not specified, a single failure marks the state as unhealthy.

tcp

The tcp structure includes a list of TCP addresses to periodically check using TCP connection attempts. Addresses must include port numbers. If a connection attempt fails, the health check will fail.

Parameter	Required	Description
addr	yes	The TCP address and port to connect to.
timeout	no	How long to wait before timing out the TCP connection. A positive integer and an optional suffix indicating the unit of time. The suffix is one of ns, us, ms, s, m, or h. If you specify a value but omit the suffix, the value is interpreted as a number of nanoseconds.
interval	no	How long to wait between repetitions of the check. A positive integer and an optional suffix indicating the unit of time. The suffix is one of ns, us, ms, s, m, or h. Defaults to 10s if the value is omitted. If you specify a value but omit the suffix, the value is interpreted as a number of nanoseconds.
threshold	no	The number of times the check must fail before the state is marked as unhealthy. If this field is not specified, a single failure marks the state as unhealthy.

proxy

proxy:
  remoteurl: https://registry-1.docker.io
  username: [username]
  password: [password]

The proxy structure allows a registry to be configured as a pull-through cache to Docker Hub. See mirror for more information. Pushing to a registry configured as a pull-through cache is unsupported.

Parameter	Required	Description
remoteurl	yes	The URL for the repository on Docker Hub.
username	no	The username registered with Docker Hub which has access to the repository.
password	no	The password used to authenticate to Docker Hub using the username specified in username.

To enable pulling private repositories (e.g. batman/robin) specify the username (such as batman) and the password for that username.

Note

: These private repositories are stored in the proxy cache's storage. Take appropriate measures to protect access to the proxy cache.

compatibility

compatibility:
  schema1:
    signingkeyfile: /etc/registry/key.json

Use the compatibility structure to configure handling of older and deprecated features. Each subsection defines such a feature with configurable behavior.

schema1

Parameter	Required	Description
signingkeyfile	no	The signing private key used to add signatures to schema1 manifests. If no signing key is provided, a new ECDSA key is generated when the registry starts.

validation

validation:
  manifests:
    urls:
      allow:
        - ^https?://([^/]+\.)*example\.com/
      deny:
        - ^https?://www\.example\.com/

disabled

The disabled flag disables the other options in the validation section. They are enabled by default. This option deprecates the enabled flag.

manifests

Use the manifests subsection to configure validation of manifests. If disabled is false, the validation allows nothing.

urls

The allow and deny options are each a list of regular expressions that restrict the URLs in pushed manifests.

If allow is unset, pushing a manifest containing URLs fails.

If allow is set, pushing a manifest succeeds only if all URLs match one of the allow regular expressions and one of the following holds:

1. deny is unset.
2. deny is set but no URLs within the manifest match any of the deny regular expressions.

Example: Development configuration

You can use this simple example for local development:

version: 0.1
log:
  level: debug
storage:
    filesystem:
        rootdirectory: /var/lib/registry
http:
    addr: localhost:5000
    secret: asecretforlocaldevelopment
    debug:
        addr: localhost:5001

This example configures the registry instance to run on port 5000, binding to localhost, with the debug server enabled. Registry data is stored in the /var/lib/registry directory. Logging is set to debug mode, which is the most verbose.

See config-example.yml for another simple configuration. Both examples are generally useful for local development.

Example: Middleware configuration

This example configures Amazon Cloudfront as the storage middleware in a registry. Middleware allows the registry to serve layers via a content delivery network (CDN). This reduces requests to the storage layer.

Cloudfront requires the S3 storage driver.

This is the configuration expressed in YAML:

middleware:
  storage:
  - name: cloudfront
    disabled: false
    options:
      baseurl: http://d111111abcdef8.cloudfront.net
      privatekey: /path/to/asecret.pem
      keypairid: asecret
      duration: 60s

See the configuration reference for Cloudfront for more information about configuration options.

Note

: Cloudfront keys exist separately from other AWS keys. See the documentation on AWS credentials for more information.