svn commit: r945364 - in /hadoop/hbase/trunk: CHANGES.txt core/src/main/javadoc/overview.html

[stack]

Author: stack
Date: Mon May 17 21:07:48 2010
New Revision: 945364

URL: http://svn.apache.org/viewvc?rev=945364&view=rev
Log:
HBASE-2382 Don't rely on fs.getDefaultReplication() to roll HLogs; committed 
the overview.html changes only

Modified:
    hadoop/hbase/trunk/CHANGES.txt
    hadoop/hbase/trunk/core/src/main/javadoc/overview.html

Modified: hadoop/hbase/trunk/CHANGES.txt
URL: 
http://svn.apache.org/viewvc/hadoop/hbase/trunk/CHANGES.txt?rev=945364&r1=945363&r2=945364&view=diff
==============================================================================
--- hadoop/hbase/trunk/CHANGES.txt (original)
+++ hadoop/hbase/trunk/CHANGES.txt Mon May 17 21:07:48 2010
@@ -320,6 +320,10 @@ Release 0.21.0 - Unreleased
                the merge of old 0.20 into TRUNK task) -- part 1.
    HBASE-2474  Bug in HBASE-2248 - mixed version reads (not allowed by spec)
    HBASE-2509  NPEs in various places, HRegion.get, HRS.close
+   HBASE-2344  InfoServer and hence HBase Master doesn't fully start if you
+               have HADOOP-6151 patch (Kannan Muthukkaruppan via Stack)
+   HBASE-2382  Don't rely on fs.getDefaultReplication() to roll HLogs
+               (Nicolas Spiegelberg via Stack)  
 
   IMPROVEMENTS
    HBASE-1760  Cleanup TODOs in HTable

Modified: hadoop/hbase/trunk/core/src/main/javadoc/overview.html
URL: 
http://svn.apache.org/viewvc/hadoop/hbase/trunk/core/src/main/javadoc/overview.html?rev=945364&r1=945363&r2=945364&view=diff
==============================================================================
--- hadoop/hbase/trunk/core/src/main/javadoc/overview.html (original)
+++ hadoop/hbase/trunk/core/src/main/javadoc/overview.html Mon May 17 21:07:48 
2010
@@ -150,14 +150,23 @@ requirements and instructions</a> for ho
 
 <h4><a name="pseudo-distrib">Pseudo-distributed mode</a></h4>
 <p>A pseudo-distributed mode is simply a distributed mode run on a single host.
-Once you have confirmed your DFS setup, configuring HBase for use on one host 
requires modification of
+Use this configuration testing and prototyping on hbase.  Do not use this 
configuration
+for production nor for evaluating HBase performance.
+</p>
+<p>Once you have confirmed your DFS setup, configuring HBase for use on one 
host requires modification of
 <code>${HBASE_HOME}/conf/hbase-site.xml</code>, which needs to be pointed at 
the running Hadoop DFS instance.
 Use <code>hbase-site.xml</code> to override the properties defined in
 <code>${HBASE_HOME}/conf/hbase-default.xml</code> 
(<code>hbase-default.xml</code> itself
-should never be modified). At a minimum the <code>hbase.rootdir</code> 
property should be redefined
-in <code>hbase-site.xml</code> to point HBase at the Hadoop filesystem to use. 
For example, adding the property
-below to your <code>hbase-site.xml</code> says that HBase should use the 
<code>/hbase</code> directory in the
-HDFS whose namenode is at port 9000 on your local machine:</p>
+should never be modified) and for HDFS client configurations.
+At a minimum, the <code>hbase.rootdir</code>,
+which points HBase at the Hadoop filesystem to use,
+and the <code>dfs.replication</code>, an hdfs client-side
+configuration stipulating how many replicas to keep up,
+should be redefined in <code>hbase-site.xml</code>. For example,
+adding the properties below to your <code>hbase-site.xml</code> says that HBase
+should use the <code>/hbase</code> 
+directory in the HDFS whose namenode is at port 9000 on your local machine, 
and that
+it should run with one replica only (recommended for pseudo-distributed 
mode):</p>
 <blockquote>
 <pre>
 &lt;configuration&gt;
@@ -168,6 +177,12 @@ HDFS whose namenode is at port 9000 on y
     &lt;description&gt;The directory shared by region servers.
     &lt;/description&gt;
   &lt;/property&gt;
+  &lt;property&gt;
+    &lt;name&gt;dfs.replication&lt;/name&gt;
+    &lt;value&gt;1&lt;/value&gt;
+    &lt;description&gt;The replication count for HLog & HFile storage. Should 
not be greater than HDFS datanode count.
+    &lt;/description&gt;
+  &lt;/property&gt;
   ...
 &lt;/configuration&gt;
 </pre>
@@ -203,7 +218,11 @@ configurations must be made <em>in addit
 </blockquote>
 
 <p>In fully-distributed mode, you probably want to change your 
<code>hbase.rootdir</code>
-from localhost to the name of the node running the HDFS NameNode. In addition
+from localhost to the name of the node running the HDFS NameNode and you 
should set
+the dfs.replication to be the number of datanodes you have in your cluster or 
3, which
+ever is the smaller.
+</p>
+<p>In addition
 to <code>hbase-site.xml</code> changes, a fully-distributed mode requires that 
you
 modify <code>${HBASE_HOME}/conf/regionservers</code>.
 The <code>regionserver</code> file lists all hosts running 
<code>HRegionServer</code>s, one host per line