Clusters are identified by a five-digit alphanumeric id (numbers and lowercase letters). There are 36 ^5^ = 60466176 possible cluster identifiers.
-* For automated tests purposes, use "z****"
+* For automated test purposes, use "z****"
* For experimental/local-only/private clusters that won't ever be visible on the public Internet, use "x****"
-* For long-lived clusters, we recommend reserving a cluster id. Contact "mailto:support@curoverse.com":support@curoverse.com
+* For long-lived clusters, we recommend reserving a cluster id. Contact "info@curii.com":mailto:info@curii.com for more information.
Cluster identifiers are mapped API server hosts one of two ways:
-* Through DNS resolution, under the @arvadosapi.com@ domain. For example, the API server for the cluster @qr1hi@ can be found at @qr1hi.arvadosapi.com@. To register a cluster id for free under @arvadosapi.com@, contact "mailto:support@curoverse.com":support@curoverse.com
+* Through DNS resolution, under the @arvadosapi.com@ domain. For example, the API server for the cluster @pirca@ can be found at @pirca.arvadosapi.com@. To register a cluster id for free under @arvadosapi.com@, contact "info@curii.com":mailto:info@curii.com
* Through explicit configuration:
The @RemoteClusters@ section of @/etc/arvados/config.yml@ (for arvados-controller)
clsr1:
RemoteClusters:
clsr2:
- Host: api.cluster2.com
+ Host: api.cluster2.example
Proxy: true
clsr3:
- Host: api.cluster3.com
+ Host: api.cluster3.example
Proxy: true
</pre>
-In this example, the cluster @clsr1@ is configured to contact @api.cluster2.com@ for requests involving @clsr2@ and @api.cluster3.com@ for requests involving @clsr3@.
+In this example, the cluster @clsr1@ is configured to contact @api.cluster2.example@ for requests involving @clsr2@ and @api.cluster3.example@ for requests involving @clsr3@.
h2(#identity). Identity
-A federated user has a single identity across the cluster federation. This identity is a user account on a specific "home cluster". When arvados-controller contacts a remote cluster, the remote cluster verifies the user's identity (see below) and then creates a mirror of the user account with the same uuid of the user's home cluster. On the remote cluster, permissions can then be granted to the federated user, and the federated user can create and own objects.
+The goal is for a federated user to have a single identity across the cluster federation. This identity is a user account on a specific "home cluster". When arvados-controller contacts a remote cluster, the remote cluster verifies the user's identity (see below) and then creates a mirror of the user account with the same uuid of the user's home cluster. On the remote cluster, permissions can then be granted to the federated user, and the federated user can create and own objects.
-h3. Authenticating remote users with salted tokens
+h3. Peer federation: Authenticating remote users with salted tokens
When making a request to the home cluster, authorization is established by looking up the API token in the @api_client_authorizations@ table to determine the user identity. When making a request to a remote cluster, we need to provide an API token which can be used to establish the user's identity. The remote cluster will connect back to the home cluster to determine if the token valid and the user it corresponds to. However, we do not want to send along the same API token used for the original request. If the remote cluster is malicious or compromised, sending along user's regular token would compromise the user account on the home cluster. Instead, the controller sends a "salted token". The salted token is restricted to only to fetching the user account and group membership. The salted token consists of the uuid of the token in @api_client_authorizations@ and the SHA1 HMAC of the original token and the cluster id of remote cluster. To verify the token, the remote cluster contacts the home cluster and provides the token uuid, the hash, and its cluster id. The home cluster uses the uuid to look up the token re-computes the SHA1 HMAC of the original token and cluster id. If that hash matches, then the token is valid. To avoid having to re-validate the token on every request, it is cached for a short period.
* Revoking a token on the home cluster also revokes it for remote clusters (after the cache period)
* A salted token given to a malicious/compromised cluster cannot be used to gain access to the user account on another remote cluster
+h3. LoginCluster federation: Centralized user database
+
+In a LoginCluster federation, there is a central "home" called the LoginCluster, and one or more "satellite" clusters. The satellite clusters delegate their user management to the LoginCluster. Unlike the peer federation, satellite clusters implicitly trust the home cluster, so the "salted token" scheme is not used. Users arriving at a satellite cluster are redirected to the home cluster for login, the user token is issued by the LoginCluster, and then the user is sent back to the satellite cluster. Tokens issued by the LoginCluster are accepted by all clusters in the federation. All requests for user records on a satellite cluster is forwarded to the LoginCluster.
+
h2(#retrieval). Federated records
!(full-width){{site.baseurl}}/images/arvados_federation.svg!
h3. Collections and Keep block retrieval
-Each collection record has @manifest_text@, which describes how to reassemble keep blocks into files as described in the "Storage in Keep.":{{site.baseurl}}/api/storage.html. Each block identifier in the manifest has an added signature which is used to confirm permission to read the block. To read a block from a keepstore server, the client must provide the block identifier, the signature, and the same API token used to retrieve the collection record.
-
-When a collection record is returned through a federation request, the keep blocks listed in the manifest may not be available on the local cluster, and the keep block signatures returned by the remote cluster are not valid for the local cluster. To solve this, arvados-controller rewrites the signatures in the manifest to "remote cluster" signatures.
-
-A local signature comes after the block identifier and block size, and starts with @+A@:
-
-<code>930625b054ce894ac40596c3f5a0d947+33+A1f27a35dd9af37191d63ad8eb8985624451e7b79@5835c8bc</code>
-
-A remote cluster signature starts with @+R@, then the cluster id of the cluster it originated from (@zzzzz@ in this example), a dash, and then the original signature:
-
-<code>930625b054ce894ac40596c3f5a0d947+33+Rzzzzz-1f27a35dd9af37191d63ad8eb8985624451e7b79@5835c8bc</code>
-
-When the client provides a remote-signed block locator to keepstore, the keepstore proxies the request to the remote cluster.
+Each collection record has @manifest_text@, which describes how to reassemble keep blocks into files as described in the "Manifest format":{{site.baseurl}}/architecture/manifest-format.html. Each block identifier in the manifest has an added signature which is used to confirm permission to read the block. To read a block from a keepstore server, the client must provide the block identifier, the signature, and the same API token used to retrieve the collection record.
-# keepstore determines the cluster id to contact from the first part of the @+R@ signature
-# creates a salted token using the API token and cluster id
-# contacts the "accessible" endpoint on the remote cluster to determine the remote cluster's keepstore or keepproxy hosts
-# converts the remote signature @+R@ back to a local signature @+A@
-# contacts the remote keepstore or keepproxy host and requests the block using the local signature
-# returns the block contents back to the client
+See "Federation signatures":{{site.baseurl}}/architecture/manifest-format.html#federationsignatures for details on how federation affects block signatures.
projects / arvados.git / blobdiff