Writing to HDFS could only be replicated to 0 nodes instead of minReplication (=1)

Question

I have 3 data nodes running, while running a job i am getting the following given below error ,

java.io.IOException: File /user/ashsshar/olhcache/load

Answer 1

In my case, this issue was resolved by opening the firewall port on 50010 on the datanodes.

Answer 2

I had the same issue, I was running very low on disk space. Freeing up disk solved it.

Answer 3

1. Check whether your DataNode is running,use the command:jps.
2. If it is not running wait sometime and retry.
3. If it is running, I think you have to re-format your DataNode.

Answer 4

1.Stop all Hadoop daemons

for x in `cd /etc/init.d ; ls hadoop*` ; do sudo service $x stop ; done

2.Remove all files from /var/lib/hadoop-hdfs/cache/hdfs/dfs/name

Eg: devan@Devan-PC:~$ sudo rm -r /var/lib/hadoop-hdfs/cache/

3.Format Namenode

sudo -u hdfs hdfs namenode -format

4.Start all Hadoop daemons

for x in `cd /etc/init.d ; ls hadoop*` ; do sudo service $x start ; done

Stop All Hadoop Service

Answer 5

What I usually do when this happens is that I go to tmp/hadoop-username/dfs/ directory and manually delete the data and name folders (assuming you are running in a Linux environment).

Then format the dfs by calling bin/hadoop namenode -format (make sure that you answer with a capital Y when you are asked whether you want to format; if you are not asked, then re-run the command again).

You can then start hadoop again by calling bin/start-all.sh

Answer 6

Very Simple fix for the same issue on Windows 8.1
I used Windows 8.1 OS and Hadoop 2.7.2, Did the following things to overcome this issue.

1. When I started the hdfs namenode -format, I noticed there is a lock in my directory. please refer the figure below.
   
2. Once I deleted the full folder as shown below, and again I did the hdfs namenode -format.
   
3. After performing above two steps, I could successfully place my required files in HDFS system. I used start-all.cmd command to start yarn and namenode.