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Re: HConnectionImplementation closed

I had same exception when my master node died.
Then I found this code:

private HRegionLocation locateRegion(byte[] tableName, byte[] row, boolean useCache) throws IOException {
if (closed) throw new IOException(toString() + " closed");

public void abort(String msg, Throwable t)
if ((t instanceof KeeperException.SessionExpiredException)) {
try {
LOG.info("This client just lost it's session with ZooKeeper, trying to reconnect.");

LOG.info("Reconnected successfully. This disconnect could have been caused by a network partition or a long-running GC pause, either way it's recommended that
you verify your environment.");

} catch (ZooKeeperConnectionException e) {
LOG.error("Could not reconnect to ZooKeeper after session expiration, aborting");

t = e;
if (t != null) LOG.fatal(msg, t); else
aborted = true;
closed = true;

So, it happens when client looses connection to ZooKeeper and cant reconnect,
Or, simply, somebody calls HConnection.close()

08.01.2013 12:41, Antony Neu пишет:
> Can anyone tell me when this exception is thrown?
> Regards,
> Antony
> Am 06.01.2013 12:35, schrieb [EMAIL PROTECTED]:
>> Hi there,
>> I'm having problems accessing HBase from within a MapReduce programme on my cluster. To locate the problem I've written a very simple test programme. It runs
>> fine on the master node, however on the other nodes I get the same error that was causing problems in the MapReduce programme:
>> java.io.IOException: org.apache.hadoop.hbase.client.HConnectionManager$HConnectionImplementation@2937d090 closed
>> at org.apache.hadoop.hbase.client.HConnectionManager$HConnectionImplementation.locateRegion(HConnectionManager.java:794)
>> at org.apache.hadoop.hbase.client.HConnectionManager$HConnectionImplementation.locateRegion(HConnectionManager.java:782)
>> at org.apache.hadoop.hbase.client.HTable.finishSetup(HTable.java:251)
>> at org.apache.hadoop.hbase.client.HTable.<init>(HTable.java:215)
>> at org.apache.hadoop.hbase.client.HTable.<init>(HTable.java:173)
>> at TestHBase.main(TestHBase.java:29)
>> This occurs after these lines in the programme:
>> Configuration conf = HBaseConfiguration.create();
>> conf.set("hbase.master", args[0]);
>> HTable table = new HTable(conf, "Table1");
>> Note: I'm note accessing HBase through the InputFormat. I simply would like to read out a few values in the setup-method of my mappers. hbase shell seems to
>> be working on all nodes just fine and I can ping and telnet the master node on port 60000 from the other nodes.
>> What could be the problem? Am i missing something? I've installed HBase with cloudera manager CDH4.
>> Kind regards,
>> Antony