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MapReduce >> mail # user >> DataNode and Tasttracker communication


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Re: DataNode and Tasttracker communication
Hello there,

     Could you please share your /etc/hosts file, if you don't mind.

Regards,
    Mohammad Tariq

On Mon, Aug 13, 2012 at 6:01 PM, Björn-Elmar Macek
<[EMAIL PROTECTED]>wrote:

> Hi,
>
> i am currently trying to run my hadoop program on a cluster. Sadly though
> my datanodes and tasktrackers seem to have difficulties with their
> communication as their logs say:
> * Some datanodes and tasktrackers seem to have portproblems of some kind
> as it can be seen in the logs below. I wondered if this might be due to
> reasons correllated with the localhost entry in /etc/hosts as you can read
> in alot of posts with similar errors, but i checked the file neither
> localhost nor 127.0.0.1/127.0.1.1 is bound there. (although you can ping
> localhost... the technician of the cluster said he'd be looking for the
> mechanics resolving localhost)
> * The other nodes can not speak with the namenode and jobtracker
> (its-cs131). Although it is absolutely not clear, why this is happening:
> the "dfs -put" i do directly before the job is running fine, which seems to
> imply that communication between those servers is working flawlessly.
>
> Is there any reason why this might happen?
>
>
> Regards,
> Elmar
>
> LOGS BELOW:
>
> \____Datanodes
>
> After successfully putting the data to hdfs (at this point i thought
> namenode and datanodes have to communicate), i get the following errors
> when starting the job:
>
> There are 2 kinds of logs i found: the first one is big (about 12MB) and
> looks like this:
> ##############################**# LOG TYPE 1
> ##############################**##############################
> 2012-08-13 08:23:27,331 INFO org.apache.hadoop.ipc.Client: Retrying
> connect to server: its-cs131/141.51.205.41:35554. Already tried 0 time(s).
> 2012-08-13 08:23:28,332 INFO org.apache.hadoop.ipc.Client: Retrying
> connect to server: its-cs131/141.51.205.41:35554. Already tried 1 time(s).
> 2012-08-13 08:23:29,332 INFO org.apache.hadoop.ipc.Client: Retrying
> connect to server: its-cs131/141.51.205.41:35554. Already tried 2 time(s).
> 2012-08-13 08:23:30,332 INFO org.apache.hadoop.ipc.Client: Retrying
> connect to server: its-cs131/141.51.205.41:35554. Already tried 3 time(s).
> 2012-08-13 08:23:31,333 INFO org.apache.hadoop.ipc.Client: Retrying
> connect to server: its-cs131/141.51.205.41:35554. Already tried 4 time(s).
> 2012-08-13 08:23:32,333 INFO org.apache.hadoop.ipc.Client: Retrying
> connect to server: its-cs131/141.51.205.41:35554. Already tried 5 time(s).
> 2012-08-13 08:23:33,334 INFO org.apache.hadoop.ipc.Client: Retrying
> connect to server: its-cs131/141.51.205.41:35554. Already tried 6 time(s).
> 2012-08-13 08:23:34,334 INFO org.apache.hadoop.ipc.Client: Retrying
> connect to server: its-cs131/141.51.205.41:35554. Already tried 7 time(s).
> 2012-08-13 08:23:35,334 INFO org.apache.hadoop.ipc.Client: Retrying
> connect to server: its-cs131/141.51.205.41:35554. Already tried 8 time(s).
> 2012-08-13 08:23:36,335 INFO org.apache.hadoop.ipc.Client: Retrying
> connect to server: its-cs131/141.51.205.41:35554. Already tried 9 time(s).
> 2012-08-13 08:23:36,335 WARN org.apache.hadoop.hdfs.server.**datanode.DataNode:
> java.net.ConnectException: Call to its-cs131/141.51.205.41:35554 failed
> on connection exception: java.net.ConnectException: Connection refused
>     at org.apache.hadoop.ipc.Client.**wrapException(Client.java:**1095)
>     at org.apache.hadoop.ipc.Client.**call(Client.java:1071)
>     at org.apache.hadoop.ipc.RPC$**Invoker.invoke(RPC.java:225)
>     at $Proxy5.sendHeartbeat(Unknown Source)
>     at org.apache.hadoop.hdfs.server.**datanode.DataNode.**
> offerService(DataNode.java:**904)
>     at org.apache.hadoop.hdfs.server.**datanode.DataNode.run(**
> DataNode.java:1458)
>     at java.lang.Thread.run(Thread.**java:619)
> Caused by: java.net.ConnectException: Connection refused
>     at sun.nio.ch.SocketChannelImpl.**checkConnect(Native Method)
>     at sun.nio.ch.SocketChannelImpl.**finishConnect(**