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## Gateway Details ##

TODO

### URL Mapping ###

The gateway functions much like a reverse proxy.
As such it maintains a mapping of URLs that are exposed externally by the gateway to URLs that are provided by the Hadoop cluster.
Examples of mappings for the WebHDFS, WebHCat, Oozie and Stargate/HBase are shown below.
These mapping are generated from the combination of the gateway configuration file (i.e. `{GATEWAY_HOME}/conf/gateway-site.xml`) and the cluster topology descriptors (e.g. `{GATEWAY_HOME}/deployments/{cluster-name}.xml`).
The port numbers show for the Cluster URLs represent the default ports for these services.
The actual port number may be different for a given cluster.

* WebHDFS
    * Gateway: `https://{gateway-host}:{gateway-port}/{gateway-path}/{cluster-name}/webhdfs`
    * Cluster: `http://{webhdfs-host}:50070/webhdfs`
* WebHCat (Templeton)
    * Gateway: `https://{gateway-host}:{gateway-port}/{gateway-path}/{cluster-name}/templeton`
    * Cluster: `http://{webhcat-host}:50111/templeton}`
* Oozie
    * Gateway: `https://{gateway-host}:{gateway-port}/{gateway-path}/{cluster-name}/oozie`
    * Cluster: `http://{oozie-host}:11000/oozie}`
* Stargate (HBase)
    * Gateway: `https://{gateway-host}:{gateway-port}/{gateway-path}/{cluster-name}/hbase`
    * Cluster: `http://{hbase-host}:60080`

The values for `{gateway-host}`, `{gateway-port}`, `{gateway-path}` are provided via the gateway configuration file (i.e. `{GATEWAY_HOME}/conf/gateway-site.xml`).

The value for `{cluster-name}` is derived from the file name of the cluster topology descriptor (e.g. `{GATEWAY_HOME}/deployments/{cluster-name}.xml`).

The value for `{webhdfs-host}`, `{webhcat-host}`, `{oozie-host}` and `{hbase-host}` are provided via the cluster topology descriptor (e.g. `{GATEWAY_HOME}/deployments/{cluster-name}.xml`).

Note: The ports 50070, 50111, 11000 and 60080 are the defaults for WebHDFS, WebHCat, Oozie and Stargate/HBase respectively.
Their values can also be provided via the cluster topology descriptor if your Hadoop cluster uses different ports.

<<config.md>>
<<knox_cli.md>>
<<config_authn.md>>
<<config_ldap_group_lookup.md>>
<<config_id_assertion.md>>
<<config_authz.md>>
<<config_kerberos.md>>
<<config_ha.md>>