I have a single machine that I use to test various things with hadoop. I
am having errors in one of the log files that make no particular sense.
This is hadoop 0.15.0
2007-12-04 16:51:28,405 ERROR org.apache.hadoop.dfs.NameNode.Secondary:
Exception in doCheckpoint:
2007-12-04 16:51:28,406 ERROR org.apache.hadoop.dfs.NameNode.Secondary:
java.net.UnknownHostException: hdfs
at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:177)
at java.net.Socket.connect(Socket.java:519)
at java.net.Socket.connect(Socket.java:469)
at sun.net.NetworkClient.doConnect(NetworkClient.java:157)
at sun.net.www.http.HttpClient.openServer(HttpClient.java:394)
at sun.net.www.http.HttpClient.openServer(HttpClient.java:529)
at sun.net.www.http.HttpClient.<init>(HttpClient.java:233)
at sun.net.www.http.HttpClient.New(HttpClient.java:306)
at sun.net.www.http.HttpClient.New(HttpClient.java:323)
at
sun.net.www.protocol.http.HttpURLConnection.getNewHttpClient(HttpURLConnection.java:788)
at
sun.net.www.protocol.http.HttpURLConnection.plainConnect(HttpURLConnection.java:729)
at
sun.net.www.protocol.http.HttpURLConnection.connect(HttpURLConnection.java:654)
at
sun.net.www.protocol.http.HttpURLConnection.getInputStream(HttpURLConnection.java:977)
at
org.apache.hadoop.dfs.TransferFsImage.getFileClient(TransferFsImage.java:142)
at
org.apache.hadoop.dfs.TransferFsImage.getFileClient(TransferFsImage.java:181)
at
org.apache.hadoop.dfs.SecondaryNameNode.getFSImage(SecondaryNameNode.java:209)
at
org.apache.hadoop.dfs.SecondaryNameNode.doCheckpoint(SecondaryNameNode.java:275)
at
org.apache.hadoop.dfs.SecondaryNameNode.run(SecondaryNameNode.java:192)
at java.lang.Thread.run(Thread.java:619)
<?xml version="1.0"?>
<?xml-stylesheet type="text/xsl" href="configuration.xsl"?>
<!-- Put site-specific property overrides in this file. -->
<configuration>
<property>
<name>hdfs://localhost:54310</name>
<value>file:///</value>
<description>The name of the default file system. A URI whose
scheme and authority determine the FileSystem implementation. The
uri's scheme determines the config property (fs.SCHEME.impl) naming
the FileSystem implementation class. The uri's authority is used to
determine the host, port, etc. for a filesystem.</description>
</property>
<property>
<name>mapred.job.tracker</name>
<value>localhost:54311</value>
<description>The host and port that the MapReduce job tracker runs
at. If "local", then jobs are run in-process as a single map
and reduce task.
</description>
</property>
<property>
<name>dfs.replication</name>
<value>1</value>
<description>Default block replication.
The actual number of replications can be specified when the file is created.
The default is used if replication is not specified in create time.
</description>
</property>
<property>
<name>mapred.map.tasks</name>
<value>7</value>
<description>The default number of map tasks per job. Typically set
to a prime several times greater than number of available hosts.
Ignored when mapred.job.tracker is "local".
</description>
</property>
<property>
<name>mapred.reduce.tasks</name>
<value>3</value>
<description>The default number of reduce tasks per job. Typically set
to a prime close to the number of available hosts. Ignored when
mapred.job.tracker is "local".
</description>
</property>
<property>
<name>mapred.tasktracker.tasks.maximum</name>
<value>2</value>
<description>The maximum number of tasks that will be run
simultaneously by a task tracker.
</description>
</property>
<property>
<name>hadoop.tmp.dir</name>
<value>/home/jason/hadoop-0.15.0/dfs</value>
<description>A base for other temporary directories.</description>
</property>
<property>
<name>dfs.block.size</name>
<value>524288</value>
<description>The default block size for new files.</description>
</property>
<property>
<name>mapred.child.java.opts</name>
<value>-Xmx400m</value>
<description>Java opts for the task tracker child processes. Subsumes
'mapred.child.heap.size' (If a mapred.child.heap.size value is found
in a configuration, its maximum heap size will be used and a warning
emitted that heap.size has been deprecated). Also, the following symbol,
if present, will be interpolated: @taskid@ is replaced by current TaskID.
Any other occurrences of '@' will go unchanged. For
example, to enable verbose gc logging to a file named for the taskid in
/tmp and to set the heap maximum to be a gigabyte, pass a 'value' of:
-Xmx1024m -verbose:gc -Xloggc:/tmp/@[EMAIL PROTECTED]
</description>
</property>
</configuration>
