When I run hadoop command like hadoop fs -ls, I get following error/warnings:
16/08/04 11:24:12 WARN util.NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applicable
ls: Call From master/172.17.100.54 to master:9000 failed on connection exception: java.net.ConnectException: Connection refused; For more details see: http://wiki.apache.org/hadoop/ConnectionRefused
Am I doing anything wrong with the hadoop path?
Hadoop Native Libraries Guide say its some thing to do with installation. please check documentation to resolve this.
Hadoop has native implementations of certain components for performance reasons and for non-availability of Java implementations. These components are available in a single, dynamically-linked native library called the native hadoop library. On the *nix platforms the library is named libhadoop.so.
Please note the following:
It is mandatory to install both the zlib and gzip development packages on the target platform in order to build the native hadoop library; however, for deployment it is sufficient to install just one package if you wish to use only one codec. It is necessary to have the correct 32/64 libraries for zlib, depending on the 32/64 bit jvm for the target platform, in order to build and deploy the native hadoop library.
Runtime
The bin/hadoop script ensures that the native hadoop library is on the library path via the system property: -Djava.library.path=<path>
During runtime, check the hadoop log files for your MapReduce tasks.
If everything is all right, then: DEBUG util.NativeCodeLoader - Trying to load the custom-built native-hadoop library... INFO util.NativeCodeLoader - Loaded the native-hadoop library
If something goes wrong, then: INFO util.NativeCodeLoader - Unable to load native-hadoop library for your platform... using builtin-java classes where applicable
Check
NativeLibraryChecker is a tool to check whether native libraries are loaded correctly. You can launch NativeLibraryChecker as follows
$ hadoop checknative -a
14/12/06 01:30:45 WARN bzip2.Bzip2Factory: Failed to load/initialize native-bzip2 library system-native, will use pure-Java version
14/12/06 01:30:45 INFO zlib.ZlibFactory: Successfully loaded & initialized native-zlib library
Native library checking:
hadoop: true /home/ozawa/hadoop/lib/native/libhadoop.so.1.0.0
zlib: true /lib/x86_64-linux-gnu/libz.so.1
snappy: true /usr/lib/libsnappy.so.1
lz4: true revision:99
bzip2: false
Second thing Connection refused is something related to your setup. please double check setup. also see the below as pointers..
Hadoop cluster setup - java.net.ConnectException: Connection refused
