Reply
Highlighted
Master
Posts: 373
Registered: ‎07-01-2015
Accepted Solution

NameNode running but 50070 not listening

[ Edited ]

Hi,

 having a non-ha setup of kerberized HDFS where the Namenode is running but 

 netstat -an | grep 50070

does not return anything (running as root on namenode host)

 The WebHDFS is enabled in CM:

dfs.webhdfs.enabled=True

 

Any hints why this port is not open and why the NN is not listening? Thanks

Cloudera Employee
Posts: 440
Registered: ‎03-23-2015

Re: NameNode running but 50070 not listening

50070 is HDFS's web UI port, it can be configured differently on each cluster.

You can check your hdfs-site.xml file and what's the value for dfs.namenode.http-address?
Master
Posts: 373
Registered: ‎07-01-2015

Re: NameNode running but 50070 not listening

Thanks for the clarification, this is the hdfs-site.xml.

I am little bit confused, so the WebHDFS REST API is listening on the same port as the NameNode's UI? 

Thanks

 

  <property>
    <name>dfs.ha.namenodes.hanameservice</name>
    <value>namenode18,namenode21</value>
  </property>
  <property>
    <name>dfs.namenode.rpc-address.hanameservice.namenode18</name>
    <value>ip-10-197-31-86.eu-west-1.compute.internal:8020</value>
  </property>
  <property>
    <name>dfs.namenode.servicerpc-address.hanameservice.namenode18</name>
    <value>ip-10-197-31-86.eu-west-1.compute.internal:8022</value>
  </property>
  <property>
    <name>dfs.namenode.http-address.hanameservice.namenode18</name>
    <value>ip-10-197-31-86.eu-west-1.compute.internal:50070</value>
  </property>
  <property>
    <name>dfs.namenode.https-address.hanameservice.namenode18</name>
    <value>ip-10-197-31-86.eu-west-1.compute.internal:50470</value>
  </property>
  <property>
    <name>dfs.namenode.rpc-address.hanameservice.namenode21</name>
    <value>ip-10-197-7-125.eu-west-1.compute.internal:8020</value>
  </property>
  <property>
    <name>dfs.namenode.servicerpc-address.hanameservice.namenode21</name>
    <value>ip-10-197-7-125.eu-west-1.compute.internal:8022</value>
  </property>
  <property>
    <name>dfs.namenode.http-address.hanameservice.namenode21</name>
    <value>ip-10-197-7-125.eu-west-1.compute.internal:50070</value>
  </property>
  <property>
    <name>dfs.namenode.https-address.hanameservice.namenode21</name>
    <value>ip-10-197-7-125.eu-west-1.compute.internal:50470</value>
Posts: 1,760
Kudos: 379
Solutions: 282
Registered: ‎07-31-2013

Re: NameNode running but 50070 not listening

> I am little bit confused, so the WebHDFS REST API is listening on the same port as the NameNode's UI?

Yes this is correct. The HTTP(S) serving port of the NameNode does multiple things: Serves the UI for browsers on / and a few other paths, serves a REST API on /webhdfs/*, etc.

WebHDFS on HDFS service is used by contacting the currently configured web port of the NameNode and DataNode(s) (the latter by following redirects, not directly).

In your case, the cluster is set to use HTTPS (TLS security) so you need to use the 50470 port, swebhdfs:// (notice the s-prefix for security) in place of webhdfs:// and https:// in place of http:// when following any WebHDFS tutorial.
Announcements