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DataNode is not starting after OS soft reboot

DataNode is not starting after OS soft reboot

New Contributor

Dear All,

I am very new to HADOOP.

We have install HADOOP with below setup

Namenode

Snamenode

Datanode1

Datanode2

Datanode3

We have taken OS soft reboot of server running Datanode3 without stopping services on Datanode3. (This was to check what issues could occur incase of server abruptly stops)

After OS reboot done successfully, I have started ambari agent on the Datanode3.

Ambari agent was started successfully.

However when now I am trying to start the services on Datanode3 from Ambari server UI. I am not able to do so due to some errors.

Request you all to help me to understand what all log files we need to check to identify the exact reason.

Regards,

Jayesh

3 REPLIES 3

Re: DataNode is not starting after OS soft reboot

@Jayesh Khanolkar,

You can check the logs under /var/log/{service-name}/{component}.log

service-name will be like hdfs,yarn,hbase etc.

component can be datanode for hdfs, resource manager for yarn, region server for hbase. You can check the respective folder for errors. Can you also attach the logs here if you are not able to solve the issue.

Thanks,

Aditya

Re: DataNode is not starting after OS soft reboot

@Jayesh Khanolkar

Check Iptables status and NFS Mount as well

service iptables status --> stop if it's running

Re: DataNode is not starting after OS soft reboot

New Contributor

Dear Divakar and Aditya,

Thanks for your valuable inputsdatanode-startup-issue.zip

Please refer attached document where I have tried to explain the issue with more details.

@ Aditya,

I do not see any log files with latest data/time under /var/log directory of affected Datanode.

@ Divakar,

NFS mount points are fine ; compared with running data node.

Coudl you please explian more about service iptables command, what exactly needs to be run,

Regards,

Jayesh