The libhdfs test currently does not run because hadoop.tmp.dir is specified as a relative path, and it looks like a side-effect of
HDFS-873 was that relative paths get made absolute, so build/test/libhdfs gets turned into /test/libhdfs, which the NN can not create. Let's make the test generate conf files that use the appropriate directory (build/test/libhdfs) specified by fully qualified URIs.
Also, are relative paths in conf files supported? If not rather than fail we should detect this and print a warning.