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Connection Refused - namenode on 8020

Rising Star

Hi,

I cannot start NameNode during the installation of XXXX. It gives me the following error,

2016-11-30 01:23:51,115 WARN datanode.DataNode (BPServiceActor.java:retrieveNamespaceInfo(222)) - Problem connecting to server:XXXXXXXXXXXXXXX:8020

I do the installation on my local and so there is not applied firewall ;however, i ran iptables commands to disable firewall rules.

When i do telnet to the 8020, it gives me the connection refused.

Can you please help me? Should i change the namenode parameters and choose different port?

SJ

5 REPLIES 5

Super Guru

@Sanaz Janbakhsh

Can you please login to Namenode machine and check if Namenode process is running?

ps -ef|grep -i namenode

If yes, can you please check if it is listening on 8020 port by running netstat command?

netstat -tulapn|grep 8020

If its listening then there seems to be connectivity issues from Datanode machine to Namenode machine, I guess given logs are from Datanode

Rising Star

Hi Kuldeep,

The namenode is stopped as I cannot start it via ambari. I'm connecting from the private network so there shouldn't be any firewall rules issues. I had launched a cluster of HDP2.5 before and it deployed fine. This time I need to launch a standalone node which I run into this issue.

]# ps -ef | grep -i namenode root 6366 5801 0 11:38 pts/0 00:00:00 grep -i namenode netstat -tulap| grep 8020

SJ

Super Guru

@Sanaz Janbakhsh

What error are you getting in Ambari when you click on start namenode?

New Contributor

@Sanaz Janbakhsh - were you able to fix this issue ? I'm getting similar issue where starting NameNode is giving Connection Refused error

-------------------------------------

  File "/usr/lib/python2.6/site-packages/resource_management/libraries/providers/hdfs_resource.py", line 292, in _get_file_status
    list_status = self.util.run_command(target, 'GETFILESTATUS', method='GET', ignore_status_codes=['404'], assertable_result=False)
  File "/usr/lib/python2.6/site-packages/resource_management/libraries/providers/hdfs_resource.py", line 179, in run_command
    _, out, err = get_user_call_output(cmd, user=self.run_user, logoutput=self.logoutput, quiet=False)
  File "/usr/lib/python2.6/site-packages/resource_management/libraries/functions/get_user_call_output.py", line 61, in get_user_call_output
    raise ExecutionFailed(err_msg, code, files_output[0], files_output[1])
resource_management.core.exceptions.ExecutionFailed: Execution of 'curl -sS -L -w '%{http_code}' -X GET 'http://nwk2-bdp-hadoop-06.gdcs-qa.apple.com:50070/webhdfs/v1/ats/done?op=GETFILESTATUS&user.name=hdfs' 1>/tmp/tmpckABub 2>/tmp/tmpNFnxOo' returned 7. curl: (7) Failed connect to nwk2-bdp-hadoop-06.gdcs-qa.apple.com:50070; Connection refused
000

New Contributor

Same issue has been faced by me, any solution to this above problem?