Copyright © 2010 Caringo, Inc.All rights reserved 48Version 5.0December 20105. If the search returns no realms,DX Storage continues to execute the method without furtherauthentication or authorization.If the search finds a security realm:1. DX Storage examines the request headers (not the object metadata) to determine if the requestheaders include an HTTP Authorization header.2. If the same privilege is granted to two realms, the first realm specified is granted the privilege.3. If the search finds a realm against which to authorize, DX Storage immediately attempts tovalidate the credentials found in the Castor-Authorization header against one of the usersand credentials found in that realm.If no user credentials are included in the client request, DX Storage challenges the client with aWWW-Authenticate header as discussed in RFC 2617. Any other issues with authorization mustbe resolved by your cluster administrator.12.6. Creating RealmsThis section discusses how to create a realm and associate it with a bucket in the cluster. Beforecontinuing, make sure you review the information discussed in Section 12.2, “Security RealmOverview”.A realm is a collection of user credentials, each of which includes an MD5 hash. It is computedfrom the string username:realm:password. You can compute the realm using a programminglanguage, or a utility like Apache htdigest or md5sum.htdigest is provided as part of the Apache distribution.NoteUser names cannot contain a colon character (:). Realm names cannot contain a coloncharacter (:) or a comma character (,).An example of creating a bucket realm follows:htdigest -c cluster_example_com_bucket cluster.example.com/bucketfred.jonesNew password:Re-type new password:htdigest cluster_example_com_bucket cluster.example.com/bucket sarah.smithNew password:Re-type new password:The preceding command creates a password file named cluster_example_com_mybucket withthe following contents:fred.jones:cluster.example.com/mybucket:2424db9aa9a308b53f914176d9d14676sarah.smith:cluster.example.com/mybucket:edaf3c313de4af2877bf08546856242b