Best Commands to find the information about the LInux OS running

uname 

uname -a

uname -v

uname --help

cat /etc/issue.net

cat /etc/redhat-release

lsb_release -a   ==> I prefer this command 

Unable to open kernel device "\\.\Global\vmx86": The system cannot find the file

Unable to open kernel device

"
.\Global\vmx86": The system cannot find the file specified. Did you reboot

after installing VMware Workstation?

Failed to initialize

Solution for this type error which occurred when opening an vmplayer. 

try to re-install the vmx86 driver

open a cmd in adminmode and navigate to the VMware installation directory and run

 vnetlib -- uninstall vmx86 

reboot

check again with the net start command - this time it should say "service name  is invalid"

then run

 vnetlib -- install vmx86 

and reboot again

now it hopefully works

Second simple solutions is 

start CMD as administrator then run  "net start vmx86".

Start a spark master worker nodes spark-shell in Windows 10

open cmd 

goto the installed folder of spark

C:\Spark>bin\spark-class.cmd org.apache.spark.deploy.master.Master

C:\Spark\bin>spark-class org.apache.spark.deploy.worker.Worker spark://192.168.5

6.1:7077

Now Another command prompt type : 

spark-shell --master spark://192.168.56.1:7077

Now the screen shot is

Now you can see the Application ID . Click on the Id and explore yourself.

Be sure top have SPARK_HOME is set in environmental variables ..

Note:
we have to open different cmd's to execute commands
cntrl+c on command line to terminate the process

HotSpot or JRockit to find which JVM is running from JAVA

f you want to know whether the currently running JVM is HotSpot or JRockit, check System.getProperty("java.vm.name"). For me, it gives Java HotSpot(TM) 64-Bit Server VM on HotSpot and Oracle JRockit(R) on JRockit, although different versions/platforms may give slightly different results, so the most reliable method may be:

String jvmName = System.getProperty("java.vm.name");
boolean isHotSpot = jvmName.toUpperCase().indexOf("HOTSPOT") != -1;
boolean isJRockit = jvmName.toUpperCase().indexOf("JROCKIT") != -1;

Thorbjørn's suggestion to use java.vendor has the problem that the same vendor may produce multiple JVMs; indeed, since Oracle's acquisitions of BEA and Sun, both HotSpot and JRockit now report the same value: Oracle Corporation

If you want to find all JVMs installed on a system: the problem with Nambari's answer, to use the command java -version, is that the JVM can be installed on a machine yet not be present in the path. For Windows, scanning the registry could be a better approach.

Spark Windows Installation ERRORS : WINUTILS.EXE , RuntimeException

Spark Installation in Windows caused two errors to start successfully without any errors. 

1. Missing binary file WINUTILS.EXE

  Solution :  Download the latest WINUTILS.EXE and place that in %HADOOP_HOME%\bin\winutils.exe 

Note: winutils.exe  should be more carefull in downloading the LATEST one

 prechecks before downloading :

  1. check whether windows is 32 or 64 bit 

  2.checking the winutils downloadable is 32 or 64 bit compatable 

Because 32 bit will work for 32 bit and 64 bit will work for 64 bit only 

2. ava.lang.RuntimeException: java.lang.RuntimeException: The root scratch dir: /t

mp/hive on HDFS should be writable. Current permissions are: rw-rw-rw-

After donwloading and importing the winutils.exe in bin folder .

create /tmp/hive  folder in C:\  using command line in admin mode 

and run the below commands 

%HADOOP_HOME%\BIN\WINUTILS.EXE chmod -R 777 \tmp\hive  

%HADOOP_HOME%\BIN\WINUTILS.EXE ls \tmp\hive 

At last you must contain C:\tmp\hive with full access to every user

in my case 

SPARK_HOME = C:\Spark\bin

HADOOP_HOME=C:\Spark

Thanks for reading