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Yarn components are not starting..in Hadoop 3.0.3 cluster setup

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I have setup Hadoop(3.0.3) cluster Pseudo distributed mode,

when I ran start-dfs.sh it is starting namenode,datanodes,secondary namenodes but when I ran start-yarn.sh it is showing warnings.The below one is the screenshot

110399-screenshot-from-2019-08-15-10-41-34.png

3 REPLIES 3

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Master Mentor

@vinith_alampall 

Can you please check if all the environment variables are setup properly?

One best way to quickly find out if anything is goig wrong or not is to run the Shell Script "start-yarn.sh" in DEBUG mode using "sh -x" option as following:   This will give us better ideal if it is failing somewhere :

Example: Running script in DEBUG mode

 

# sh -x ./start-yarn.sh 

 

 

Can you please share the whole output fo the above command? 
Also do you see any log is generated for the failure? Like any out/log file if yes then can you please share those logs as well?

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@jsensharma  sir,

I ran the command you mentioned it is giving below error

sh: 0: Can't open ./start-yarn.sh

below is the screenshot

Screenshot from 2019-08-19 16-05-10.png

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Master Mentor

@vinith_alampall 

As you are getting this error:

sh: 0: Can't open ./start-yarn.sh

 

Hence you should check couple of things:

 

1. Is this file existing in the current directory?

# cd /PATH/TO
# ls -lart  /PATH/TO/start-yarn.sh

2. What is the permission on the file? Can the current user read/execute it?

# chmod  a+x  /PATH/TO/start-yarn.sh

# which sh
# sh -x /PATH/TO/start-yarn.sh

 

Please replace the '/PATH/TO" with the actual path of the mentioned script.


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