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  Authentication for Hadoop HTTP web-consoles
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Authentication for Hadoop HTTP web-consoles

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* Introduction

   This document describes how to configure Hadoop HTTP web-consoles to
   require user authentication.

   By default Hadoop HTTP web-consoles (JobTracker, NameNode, TaskTrackers
   and DataNodes) allow access without any form of authentication.

   Similarly to Hadoop RPC, Hadoop HTTP web-consoles can be configured to
   require Kerberos authentication using HTTP SPNEGO protocol (supported
   by browsers like Firefox and Internet Explorer).

   In addition, Hadoop HTTP web-consoles support the equivalent of
   Hadoop's Pseudo/Simple authentication. If this option is enabled, user
   must specify their user name in the first browser interaction using the
   user.name query string parameter. For example:
   <<<http://localhost:50030/jobtracker.jsp?user.name=babu>>>.

   If a custom authentication mechanism is required for the HTTP
   web-consoles, it is possible to implement a plugin to support the
   alternate authentication mechanism (refer to Hadoop hadoop-auth for details
   on writing an <<<AuthenticatorHandler>>>).

   The next section describes how to configure Hadoop HTTP web-consoles to
   require user authentication.

* Configuration

   The following properties should be in the <<<core-site.xml>>> of all the
   nodes in the cluster.

   <<<hadoop.http.filter.initializers>>>: add to this property the
   <<<org.apache.hadoop.security.AuthenticationFilterInitializer>>> initializer
   class.

   <<<hadoop.http.authentication.type>>>: Defines authentication used for the
   HTTP web-consoles. The supported values are: <<<simple>>> | <<<kerberos>>> |
   <<<#AUTHENTICATION_HANDLER_CLASSNAME#>>>. The dfeault value is <<<simple>>>.

   <<<hadoop.http.authentication.token.validity>>>: Indicates how long (in
   seconds) an authentication token is valid before it has to be renewed.
   The default value is <<<36000>>>.

   <<<hadoop.http.authentication.signature.secret.file>>>: The signature secret
   file for signing the authentication tokens. The same secret should be used 
   for all nodes in the cluster, JobTracker, NameNode, DataNode and TastTracker. 
   The default value is <<<${user.home}/hadoop-http-auth-signature-secret>>>.
   IMPORTANT: This file should be readable only by the Unix user running the
   daemons.

   <<<hadoop.http.authentication.cookie.domain>>>: The domain to use for the
   HTTP cookie that stores the authentication token. In order to
   authentiation to work correctly across all nodes in the cluster the
   domain must be correctly set. There is no default value, the HTTP
   cookie will not have a domain working only with the hostname issuing
   the HTTP cookie.

   IMPORTANT: when using IP addresses, browsers ignore cookies with domain
   settings. For this setting to work properly all nodes in the cluster
   must be configured to generate URLs with <<<hostname.domain>>> names on it.

   <<<hadoop.http.authentication.simple.anonymous.allowed>>>: Indicates if
   anonymous requests are allowed when using 'simple' authentication. The
   default value is <<<true>>>

   <<<hadoop.http.authentication.kerberos.principal>>>: Indicates the Kerberos
   principal to be used for HTTP endpoint when using 'kerberos'
   authentication. The principal short name must be <<<HTTP>>> per Kerberos HTTP
   SPNEGO specification. The default value is <<<HTTP/_HOST@$LOCALHOST>>>,
   where <<<_HOST>>> -if present- is replaced with bind address of the HTTP
   server.

   <<<hadoop.http.authentication.kerberos.keytab>>>: Location of the keytab file
   with the credentials for the Kerberos principal used for the HTTP
   endpoint. The default value is <<<${user.home}/hadoop.keytab>>>.i