HDFS-13492. Limit httpfs binds to certain IP addresses in branch-2. Contributed by Wei-Chiu Chuang.

hadoop-hdfs-project/hadoop-hdfs-httpfs/src/main/tomcat/server.xml

@@ -69,7 +69,8 @@
          APR (HTTP/AJP) Connector: /docs/apr.html
          Define a non-SSL HTTP/1.1 Connector on port ${httpfs.http.port}
     -->
-    <Connector port="${httpfs.http.port}" protocol="HTTP/1.1"
+    <Connector address="${httpfs.http.hostname}"
+               port="${httpfs.http.port}" protocol="HTTP/1.1"
                connectionTimeout="20000"
                maxHttpHeaderSize="${httpfs.max.http.header.size}"
                redirectPort="8443"/>

hadoop-hdfs-project/hadoop-hdfs-httpfs/src/main/tomcat/ssl-server.xml

@@ -68,7 +68,8 @@
          This connector uses the JSSE configuration, when using APR, the
          connector should be using the OpenSSL style configuration
          described in the APR documentation -->
-    <Connector port="${httpfs.http.port}" protocol="HTTP/1.1" SSLEnabled="true"
+    <Connector address="${httpfs.http.hostname}"
+               port="${httpfs.http.port}" protocol="HTTP/1.1" SSLEnabled="true"
                maxThreads="150" scheme="https" secure="true"
                maxHttpHeaderSize="${httpfs.max.http.header.size}"
                clientAuth="${httpfs.ssl.client.auth}"

hadoop-hdfs-project/hadoop-hdfs-httpfs/src/site/markdown/ServerSetup.md.vm

@@ -72,13 +72,14 @@ Embedded Tomcat Configuration
 
 To configure the embedded Tomcat go to the `tomcat/conf`.
 
-HttpFS preconfigures the HTTP and Admin ports in Tomcat's `server.xml` to 14000 and 14001.
+HttpFS preconfigures the HTTP and Admin ports in Tomcat's `server.xml` to 14000 and 14001, and it binds to all IP addresses on the host.
 
 Tomcat logs are also preconfigured to go to HttpFS's `logs/` directory.
 
 HttpFS default value for the maxHttpHeaderSize parameter in Tomcat's `server.xml` is set to 65536 by default.
 
 The following environment variables (which can be set in HttpFS's `etc/hadoop/httpfs-env.sh` script) can be used to alter those values:
+* HTTPFS\_HTTP\_HOSTNAME
 
 * HTTPFS\_HTTP\_PORT