1. hadoop-version is not recognized if run ant command from src/contrib/ or from src/contrib/hdfsproxy
If running ant command from $HADOOP_HDFS_HOME, hadoop-version will be passed to contrib's build through subant. But if running from src/contrib or src/contrib/hdfsproxy, the hadoop-version will not be recognized.
2. LdapIpDirFilter.java is not thread safe. userName, Group & Paths are per request and can't be class members.
3. Addressed the following StackOverflowError.
ost].[/].[proxyForward]] Servlet.service() for servlet proxyForward threw exception
This is due to when the target war (/target.war) does not exist, the forwarding war will forward to its parent context path /, which defines the forwarding war itself. This cause infinite loop. Added "HDFS Proxy Forward".equals(dstContext.getServletContextName() in the if logic to break the loop.
4. Kerberos credentials of remote user aren't available. HdfsProxy needs to act on behalf of the real user to service the requests