| HDFSPROXY is an HTTPS proxy server that exposes the same HSFTP interface as a |
| real cluster. It authenticates users via user certificates and enforce access |
| control based on configuration files. |
| |
| Starting up an HDFSPROXY server is similar to starting up an HDFS cluster. |
| Simply run "hdfsproxy" shell command. The main configuration file is |
| hdfsproxy-default.xml, which should be on the classpath. hdfsproxy-env.sh |
| can be used to set up environmental variables. In particular, JAVA_HOME should |
| be set. Additional configuration files include user-certs.xml, |
| user-permissions.xml and ssl-server.xml, which are used to specify allowed user |
| certs, allowed directories/files, and ssl keystore information for the proxy, |
| respectively. The location of these files can be specified in |
| hdfsproxy-default.xml. Environmental variable HDFSPROXY_CONF_DIR can be used to |
| point to the directory where these configuration files are located. The |
| configuration files of the proxied HDFS cluster should also be available on the |
| classpath (hdfs-default.xml and hdfs-site.xml). |
| |
| Mirroring those used in HDFS, a few shell scripts are provided to start and |
| stop a group of proxy servers. The hosts to run hdfsproxy on are specified in |
| hdfsproxy-hosts file, one host per line. All hdfsproxy servers are stateless |
| and run independently from each other. Simple load balancing can be set up by |
| mapping all hdfsproxy server IP addresses to a single hostname. Users should |
| use that hostname to access the proxy. If an IP address look up for that |
| hostname returns more than one IP addresses, an HFTP/HSFTP client will randomly |
| pick one to use. |
| |
| Command "hdfsproxy -reloadPermFiles" can be used to trigger reloading of |
| user-certs.xml and user-permissions.xml files on all proxy servers listed in |
| the hdfsproxy-hosts file. Similarly, "hdfsproxy -clearUgiCache" command can be |
| used to clear the UGI caches on all proxy servers. |
