diff --git a/CHANGES.txt b/CHANGES.txt index 23f298bd799..795ef7d4370 100644 --- a/CHANGES.txt +++ b/CHANGES.txt @@ -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 diff --git a/core/src/main/javadoc/overview.html b/core/src/main/javadoc/overview.html index 45251d90080..230f98758ed 100644 --- a/core/src/main/javadoc/overview.html +++ b/core/src/main/javadoc/overview.html @@ -150,14 +150,23 @@ requirements and instructions for how to set up a DFS.
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. +
+Once you have confirmed your DFS setup, configuring HBase for use on one host requires modification of
${HBASE_HOME}/conf/hbase-site.xml
, which needs to be pointed at the running Hadoop DFS instance.
Use hbase-site.xml
to override the properties defined in
${HBASE_HOME}/conf/hbase-default.xml
(hbase-default.xml
itself
-should never be modified). At a minimum the hbase.rootdir
property should be redefined
-in hbase-site.xml
to point HBase at the Hadoop filesystem to use. For example, adding the property
-below to your hbase-site.xml
says that HBase should use the /hbase
directory in the
-HDFS whose namenode is at port 9000 on your local machine:
hbase.rootdir
,
+which points HBase at the Hadoop filesystem to use,
+and the dfs.replication
, an hdfs client-side
+configuration stipulating how many replicas to keep up,
+should be redefined in hbase-site.xml
. For example,
+adding the properties below to your hbase-site.xml
says that HBase
+should use the /hbase
+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):
<configuration> @@ -168,6 +177,12 @@ HDFS whose namenode is at port 9000 on your local machine: <description>The directory shared by region servers. </description> </property> + <property> + <name>dfs.replication</name> + <value>1</value> + <description>The replication count for HLog & HFile storage. Should not be greater than HDFS datanode count. + </description> + </property> ... </configuration>@@ -203,7 +218,11 @@ configurations must be made in addition to those described in the
In fully-distributed mode, you probably want to change your hbase.rootdir
-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.
+
In addition
to hbase-site.xml
changes, a fully-distributed mode requires that you
modify ${HBASE_HOME}/conf/regionservers
.
The regionserver
file lists all hosts running HRegionServer
s, one host per line