This happens to me, when the dfs has gotten into an inconsistent state.
NOTE: you will lose all of the contents of your HDS file system.
What I hae to do, is stop dfs, remove the contents of the dfs
directories on all the machines, hadoop namenode -format on the
controller, then restart dfs.
That consistently fixes the problem for me. This may be serious overkill
but it works.
NOTE: you will lose all of the contents of your HDS file system.
jerrro wrote:
I am trying to install/configure hadoop on a cluster with several computers.
I followed exactly the instructions in the hadoop website for configuring
multiple slaves, and when I run start-all.sh I get no errors - both datanode
and tasktracker are reported to be running (doing ps awux | grep hadoop on
the slave nodes returns two java processes). Also, the log files are empty -
nothing is printed there. Still, when I try to use bin/hadoop dfs -put,
I get the following error:
# bin/hadoop dfs -put w.txt w.txt
put: java.io.IOException: File /user/scohen/w4.txt could only be replicated
to 0 nodes, instead of 1
and a file of size 0 is created on the DFS (bin/hadoop dfs -ls shows it).
I couldn't find much information about this error, but I did manage to see
somewhere it might mean that there are no datanodes running. But as I said,
start-all does not give any errors. Any ideas what could be problem?
Thanks.
Jerr.
