Hadoop dfs error: INFO ipc.Client: retrying server connection: localhost

Question

I successfully installed a 6-node Hadoop cluster (master, salve <1-5>)

• Formatted namenode -> done
• Starting and shutting down a cluster -> works fine
• Running "hadoop dfs -ls /" gives this error -> Error: INFO ipc.Client: trying to connect to the server again: localhost

I tried to browse services using:

sudo netstat -plten | grep java hduser@ubuntu :~$ sudo netstat -plten | grep java 

tcp 0 0 0.0.0.0► 0070 0.0.0.0:* LISTEN 1000 93307 11384 / java
tcp 0 0 0.0.0.0-00-004440 0.0.0.0:* LISTEN 1000 92491 11571 / java
tcp 0 0 0.0.0.0:40633 0.0.0.0:* LISTEN 1000 92909 11758 / java
tcp 0 0 0.0.0.0► 0010 0.0.0.0:* LISTEN 1000 93449 11571 / java
tcp 0 0 0.0.0.0► 0075 0.0.0.0:* LISTEN 1000 93673 11571 / java
tcp 0 0 0.0.0.0► 0020 0.0.0.0:* LISTEN 1000 93692 11571 / java
tcp 0 0 127.0.0.1:40485 0.0.0.0:* LISTEN 1000 93666 12039 / java
tcp 0 0 0.0.0.0-00-004582 0.0.0.0:* LISTEN 1000 93 013 11852 / java
tcp 0 0 10.42.43.1/104310 0.0.0.0:* LISTEN 1000 92471 11384 / java
tcp 0 0 10.42.43.1/104311 0.0.0.0:* LISTEN 1000 93290 11852 / java
tcp 0 0 0.0.0.0► 0090 0.0.0.0:* LISTEN 1000 93460 11758 / java
tcp 0 0 0.0.0.0:34154 0.0.0.0:* LISTEN 1000 92179 11384 / java
tcp 0 0 0.0.0.0► 0060 0.0.0.0:* LISTEN 1000 94200 12039 / java
tcp 0 0 0.0.0.0► 0030 0.0.0.0:* LISTEN 1000 93550 11852 / java

Its main IP address is bound to ports 54310 and 54311, and not to localhost (loopback).

Conf-site.xml is configured correctly:

 <configuration> <property> <name>hadoop.tmp.dir</name> <value>/home/hduser/hadoop/tmp</value> </property> <property> <name>fs.default.name</name> <value>hdfs://master:54310</value> </property> </configuration> 

Why is it expected that localhost will be bound to 54310, and not to the host that I configured here. Help evaluate. How to solve this problem?

Greetings

Answer 1

Apparently, someone added the old bino (1.0.3) bin directory to the path variable before I added the new bino (1.0.4) bin directory. And thus, whenever I ran hadoop from the CLI, it would execute the binaries of an older house, not a new one.

Decision:

• Remove all the path bin elder chaos

• Disconnect cluster - exit the terminal

• Entering a new terminal session

• Launch node

• Tried hadoop dfs -ls / → Works great !!!! Good lesson.

Answer 2

It seems that many people have run into this problem.

It is not possible to modify / etc / hosts and make sure that you can access master and slave from each other, and your core-site.xml is the same, which indicates the correct node master and port number.

Then run $ HADOOP / bin / stop-all.sh, $ HADOOP / bin / start-all.sh on the main node ONLY. (If running on a slave can lead to problems). Use JPS to check for all services as follows.

In the main node: 4353 DataNode 4640 JobTracker 4498 SecondaryNameNode 4788 TaskTracker 4989 Jps 4216 NameNode

Slave node: 3143 Jps 2827 DataNode 2960 TaskTracker

Answer 3

Also, check the firewall rules between namenode and datanode