Author: stack
Date: Tue Nov 3 19:14:39 2009
New Revision: 832518
URL: http://svn.apache.org/viewvc?rev=832518&view=rev
Log:
HBASE-1953 Overhaul of overview.html (html fixes, typos, consistency) - no
content changes
Modified:
hadoop/hbase/branches/0.20/CHANGES.txt
hadoop/hbase/branches/0.20/src/java/overview.html
Modified: hadoop/hbase/branches/0.20/CHANGES.txt
URL:
http://svn.apache.org/viewvc/hadoop/hbase/branches/0.20/CHANGES.txt?rev=832518&r1=832517&r2=832518&view=diff
==============================================================================
--- hadoop/hbase/branches/0.20/CHANGES.txt (original)
+++ hadoop/hbase/branches/0.20/CHANGES.txt Tue Nov 3 19:14:39 2009
@@ -25,6 +25,8 @@
HBASE-1941 Put's copy feature has a bug (Dave Latham via Stack)
HBASE-1682 IndexedRegion does not properly handle deletes
(Andrew McCall via Clint Morgan and Stack)
+ HBASE-1953 Overhaul of overview.html (html fixes, typos, consistency) -
+ no content changes (Lars Francke via Stack)
IMPROVEMENTS
HBASE-1899 Use scanner caching in shell count
Modified: hadoop/hbase/branches/0.20/src/java/overview.html
URL:
http://svn.apache.org/viewvc/hadoop/hbase/branches/0.20/src/java/overview.html?rev=832518&r1=832517&r2=832518&view=diff
==============================================================================
--- hadoop/hbase/branches/0.20/src/java/overview.html (original)
+++ hadoop/hbase/branches/0.20/src/java/overview.html Tue Nov 3 19:14:39 2009
@@ -26,8 +26,25 @@
<h2>Table of Contents</h2>
<ul>
-<li><a href="#requirements">Requirements</a></li>
-<li><a href="#getting_started" >Getting Started</a></li>
+<li>
+ <a href="#requirements">Requirements</a>
+ <ul>
+ <li><a href="#windows">Windows</a></li>
+ </ul>
+</li>
+<li>
+ <a href="#getting_started" >Getting Started</a>
+ <ul>
+ <li><a href="#standalone">Standalone</a></li>
+ <li>
+ <a href="#distributed">Distributed Operation: Pseudo- and
Fully-distributed modes</a>
+ <ul>
+ <li><a href="#pseudo-distrib">Pseudo-distributed</a></li>
+ <li><a href="#fully-distrib">Fully-distributed</a></li>
+ </ul>
+ </li>
+ </ul>
+</li>
<li><a href="#runandconfirm">Running and Confirming Your Installation</a></li>
<li><a href="#upgrading" >Upgrading</a></li>
<li><a href="#client_example">Example API Usage</a></li>
@@ -36,60 +53,59 @@
<h2><a name="requirements">Requirements</a></h2>
<ul>
- <li>Java 1.6.x, preferably from <a
href="http://www.java.com/en/download/";>Sun</a>.
- Use the latest version available.
+ <li>Java 1.6.x, preferably from <a
href="http://www.java.com/download/";>Sun</a>. Use the latest version
available.</li>
+ <li>This version of HBase will only run on <a
href="http://hadoop.apache.org/common/releases.html";>Hadoop 0.20.x</a>.</li>
+ <li><i>ssh</i> must be installed and <i>sshd</i> must be running to use
Hadoop's scripts to manage remote Hadoop daemons.
+ You must be able to ssh to all nodes, including your local node, using
passwordless login
+ (Google "ssh passwordless login").
+</li>
+ <li>
+ HBase depends on <a
href="http://hadoop.apache.org/zookeeper/";>ZooKeeper</a> as of release 0.20.0.
+ HBase keeps the location of its root table, who the current master is, and
what regions are
+ currently participating in the cluster in ZooKeeper.
+ Clients and Servers now must know their <em>ZooKeeper Quorum
locations</em> before
+ they can do anything else (Usually they pick up this information from
configuration
+ supplied on their CLASSPATH). By default, HBase will manage a single
ZooKeeper instance for you.
+ In <em>standalone</em> and <em>pseudo-distributed</em> modes this is
usually enough, but for
+ <em>fully-distributed</em> mode you should configure a ZooKeeper quorum
(more info below).
</li>
- <li>This version of HBase will only run on <a
href="http://hadoop.apache.org/core/releases.html";>Hadoop 0.20.x</a>.
+ <li>Hosts must be able to resolve the fully-qualified domain name of the
master.</li>
+ <li>
+ HBase currently is a file handle hog. The usual default of 1024 on *nix
systems is insufficient
+ if you are loading any significant amount of data into regionservers.
+ See the <a href="http://wiki.apache.org/hadoop/Hbase/FAQ#A6";>FAQ: Why do I
see "java.io.IOException...(Too many open files)" in my logs?</a>
+ for how to up the limit. Also, as of 0.18.x Hadoop DataNodes have an
upper-bound on the number of threads they will
+ support (<code>dfs.datanode.max.xcievers</code>). The default is 256
threads. Up this limit on your hadoop cluster.
</li>
<li>
- ssh must be installed and sshd must be running to use Hadoop's
- scripts to manage remote Hadoop daemons.
+ The clocks on cluster members should be in basic alignments. Some skew is
tolerable but
+ wild skew could generate odd behaviors. Run <a
href="http://en.wikipedia.org/wiki/Network_Time_Protocol";>NTP</a>
+ on your cluster, or an equivalent.
</li>
- <li>HBase depends on <a
href="http://hadoop.apache.org/zookeeper/";>ZooKeeper</a> as of release 0.20.0.
- Clients and Servers now must know where their ZooKeeper Quorum locations
before
- they can do anything else (Usually they pick up this information from
configuration
- supplied on their CLASSPATH). By default, HBase will manage a single
ZooKeeper instance for you.
- In basic standalone and pseudo-distributed modes this is usually enough,
but for fully
- distributed mode you should configure a ZooKeeper quorum (more info
below).
- In addition ZooKeeper changes how some core HBase configuration is done.
- </li>
- <li>Hosts must be able to resolve the fully-qualified domain name of the
master.</li>
- <li>HBase currently is a file handle hog. The usual default of
- 1024 on *nix systems is insufficient if you are loading any significant
- amount of data into regionservers. See the
- <a href="http://wiki.apache.org/hadoop/Hbase/FAQ#6";>FAQ: Why do I see
"java.io.IOException...(Too many open files)" in my logs?</a>
- for how to up the limit. Also, as of 0.18.x hadoop, datanodes have an
upper-bound
- on the number of threads they will support
(<code>dfs.datanode.max.xcievers</code>).
- Default is 256. Up this limit on your hadoop cluster.
- <li>The clocks on cluster members should be in basic alignments. Some
skew is tolerable but
- wild skew can generate odd behaviors. Run <a
href="http://en.wikipedia.org/wiki/Network_Time_Protocol";>NTP</a>
- on your cluster, or an equivalent.</li>
- <li>HBase servers put up 10 listeners for incoming connections by
default. Up this
- number if you have a dataset of any substance by setting
hbase.regionserver.handler.count
- in your hbase-site.xml.</li>
- <li>This is a list of patches we recommend you apply to your running
Hadoop cluster:
- <ul>
- <li><a
hef="https://issues.apache.org/jira/browse/HADOOP-4681";>HADOOP-4681/HDFS-127
<i>"DFSClient block read failures cause open DFSInputStream to become
unusable"</i></a>. This patch will help with the ever-popular, "No live nodes
contain current block".
- The hadoop version bundled with hbase has this patch applied. Its an
HDFS client
- fix so this should do for usual usage but if your cluster is missing the
patch,
- and in particular if calling hbase from a mapreduce job, you may run
into this
- issue.
- </li>
- <li><a hef="https://issues.apache.org/jira/browse/HDFS-630";>HDFS-630 <i>
"In DFSOutputStream.nextBlockOutputStream(), the client can exclude specific
datanodes when locating the next block"</i></a>. Dead datanodes take ten
minutes to timeout at namenode.
- Meantime the namenode can still send DFSClients to the dead datanode as
host for
- a replicated block. DFSClient can get stuck on trying to get block from
a
- dead node. This patch allows DFSClients pass namenode lists of known
- dead datanodes.
-</li>
- </ul>
+ <li>
+ HBase servers put up 10 listeners for incoming connections by default.
+ Up this number if you have a dataset of any substance by setting
<code>hbase.regionserver.handler.count</code>
+ in your <code>hbase-site.xml</code>.
+ </li>
+ <li>This is the current list of patches we recommend you apply to your
running Hadoop cluster:
+ <ul>
+ <li>
+ <a href="https://issues.apache.org/jira/browse/HDFS-630";>HDFS-630:
<em>"In DFSOutputStream.nextBlockOutputStream(), the client can exclude
specific datanodes when locating the next block"</em></a>.
+ Dead DataNodes take ten minutes to timeout at NameNode.
+ In the meantime the NameNode can still send DFSClients to the dead
DataNode as host for
+ a replicated block. DFSClient can get stuck on trying to get block
from a
+ dead node. This patch allows DFSClients pass NameNode lists of known
dead DataNodes.
</li>
+ </ul>
+ </li>
</ul>
-<h3>Windows</h3>
+
+<h3><a name="windows">Windows</a></h3>
If you are running HBase on Windows, you must install <a
href="http://cygwin.com/";>Cygwin</a>.
-Additionally, it is <emph>strongly recommended</emph> that you add or append
to the following
+Additionally, it is <em>strongly recommended</em> that you add or append to
the following
environment variables. If you install Cygwin in a location that is not
<code>C:\cygwin</code> you
should modify the following appropriately.
-<p>
+
<blockquote>
<pre>
HOME=c:\cygwin\home\jim
@@ -99,49 +115,46 @@
SHELL=/bin/bash
</pre>
</blockquote>
-For additional information, see the
-<a href="http://hadoop.apache.org/core/docs/current/quickstart.html";>Hadoop
Quick Start Guide</a>
-</p>
+For additional information, see the <a
href="http://hadoop.apache.org/common/docs/current/quickstart.html";>Hadoop
Quick Start Guide</a>
+
+
<h2><a name="getting_started" >Getting Started</a></h2>
-<p>
-What follows presumes you have obtained a copy of HBase,
+<p>What follows presumes you have obtained a copy of HBase,
see <a href="http://hadoop.apache.org/hbase/releases.html";>Releases</a>, and
are installing
-for the first time. If upgrading your
-HBase instance, see <a href="#upgrading">Upgrading</a>.
-</p>
-<p>Three modes are described: standalone, pseudo-distributed (where all
servers are run on
-a single host), and distributed. If new to hbase start by following the
standalone instruction.
-</p>
-<p>
-Whatever your mode, define <code>${HBASE_HOME}</code> to be the location of
the root of your HBase installation, e.g.
-<code>/user/local/hbase</code>. Edit
<code>${HBASE_HOME}/conf/hbase-env.sh</code>. In this file you can
-set the heapsize for HBase, etc. At a minimum, set <code>JAVA_HOME</code> to
point at the root of
-your Java installation.
-</p>
-<h3><a name="standalone">Standalone Mode</a></h3>
-<p>
-If you are running a standalone operation, there should be nothing further to
configure; proceed to
-<a href=#runandconfirm>Running and Confirming Your Installation</a>. If you
are running a distributed
-operation, continue reading.
-</p>
+for the first time. If upgrading your HBase instance, see <a
href="#upgrading">Upgrading</a>.</p>
-<h3><a name="distributed">Distributed Operation: Pseudo- and Fully-Distributed
Modes</a></h3>
-<p>Distributed mode requires an instance of the Hadoop Distributed File System
(DFS).
-See the Hadoop <a
href="http://lucene.apache.org/hadoop/api/overview-summary.html#overview_description";>
-requirements and instructions</a> for how to set up a DFS.
+<p>Three modes are described: <em>standalone</em>, <em>pseudo-distributed</em>
(where all servers are run on
+a single host), and <em>fully-distributed</em>. If new to HBase start by
following the standalone instructions.
</p>
-<h4><a name="pseudo-distrib">Pseudo-Distributed Operation</a></h4>
-<p>A pseudo-distributed operation is simply a distributed operation run on a
single host.
-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>Begin by reading <a href=#requirements>Requirements</a>.
</p>
+<p>Whatever your mode, define <code>${HBASE_HOME}</code> to be the location of
the root of your HBase installation, e.g.
+<code>/user/local/hbase</code>. Edit
<code>${HBASE_HOME}/conf/hbase-env.sh</code>. In this file you can
+set the heapsize for HBase, etc. At a minimum, set <code>JAVA_HOME</code> to
point at the root of
+your Java installation.</p>
+
+<h3><a name="standalone">Standalone mode</a></h3>
+<p>If you are running a standalone operation, there should be nothing further
to configure; proceed to
+<a href="#runandconfirm">Running and Confirming Your Installation</a>. If you
are running a distributed
+operation, continue reading.</p>
+
+<h3><a name="distributed">Distributed Operation: Pseudo- and Fully-distributed
modes</a></h3>
+<p>Distributed modes require an instance of the <em>Hadoop Distributed File
System</em> (DFS).
+See the Hadoop <a
href="http://hadoop.apache.org/common/docs/r0.20.1/api/overview-summary.html#overview_description";>
+requirements and instructions</a> for how to set up a DFS.</p>
+
+<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
+<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>
+<blockquote>
<pre>
<configuration>
...
@@ -154,17 +167,20 @@
...
</configuration>
</pre>
-<p>Note: Let hbase create the directory. If you don't, you'll get warning
saying hbase
-needs a migration run because the directory is missing files expected by hbase
(it'll
-create them if you let it).
-</p>
+</blockquote>
+
+<p>Note: Let HBase create the directory. If you don't, you'll get warning
saying HBase
+needs a migration run because the directory is missing files expected by HBase
(it'll
+create them if you let it).</p>
+<p>Also Note: Above we bind to localhost. This means that a remote client
cannot
+connect. Amend accordingly, if you want to connect from a remote location.</p>
-<h3><a name="fully-distrib">Fully-Distributed Operation</a></h3>
+<h4><a name="fully-distrib">Fully-Distributed Operation</a></h4>
<p>For running a fully-distributed operation on more than one host, the
following
configurations must be made <i>in addition</i> to those described in the
-<a href="#pseudo-distrib">pseudo-distributed operation</a> section above.
-In this mode, a ZooKeeper cluster is required.</p>
-<p>In <code>hbase-site.xml</code>, set <code>hbase.cluster.distributed</code>
to 'true'.
+<a href="#pseudo-distrib">pseudo-distributed operation</a> section above.</p>
+
+<p>In <code>hbase-site.xml</code>, set <code>hbase.cluster.distributed</code>
to <code>true</code>.</p>
<blockquote>
<pre>
<configuration>
@@ -181,65 +197,56 @@
</configuration>
</pre>
</blockquote>
-</p>
-<p>
-In fully-distributed operation, you probably want to change your
<code>hbase.rootdir</code>
-from localhost to the name of the node running the HDFS namenode. In addition
-to <code>hbase-site.xml</code> changes, a fully-distributed operation requires
that you
-modify <code>${HBASE_HOME}/conf/regionservers</code>.
-The <code>regionserver</code> file lists all hosts running HRegionServers, one
host per line
-(This file in HBase is like the hadoop slaves file at
<code>${HADOOP_HOME}/conf/slaves</code>).
-</p>
-<p>
-A distributed HBase depends on a running ZooKeeper cluster.
-HBase can manage a ZooKeeper cluster for you, or you can manage it on your own
-and point HBase to it.
-To toggle this option, use the <code>HBASE_MANAGES_ZK</code> variable in <code>
-${HBASE_HOME}/conf/hbase-env.sh</code>.
+
+<p>In fully-distributed mode, you probably want to change your
<code>hbase.rootdir</code>
+from localhost to the name of the node running the HDFS NameNode. In addition
+to <code>hbase-site.xml</code> changes, a fully-distributed mode requires that
you
+modify <code>${HBASE_HOME}/conf/regionservers</code>.
+The <code>regionserver</code> file lists all hosts running
<code>HRegionServer</code>s, one host per line
+(This file in HBase is like the Hadoop slaves file at
<code>${HADOOP_HOME}/conf/slaves</code>).</p>
+
+<p>A distributed HBase depends on a running ZooKeeper cluster. All
participating nodes and clients
+need to be able to get to the running ZooKeeper cluster.
+HBase by default manages a ZooKeeper cluster for you, or you can manage it on
your own and point HBase to it.
+To toggle HBase management of ZooKeeper, use the <code>HBASE_MANAGES_ZK</code>
variable in <code>${HBASE_HOME}/conf/hbase-env.sh</code>.
This variable, which defaults to <code>true</code>, tells HBase whether to
-start/stop the ZooKeeper quorum servers alongside the rest of the servers.
-</p>
-<p>
-To point HBase at an existing ZooKeeper cluster, add your <code>zoo.cfg</code>
-to the <code>CLASSPATH</code>.
+start/stop the ZooKeeper quorum servers alongside the rest of the servers.</p>
+
+<p>When HBase manages the ZooKeeper cluster, you can specify ZooKeeper
configuration
+using its canonical <code>zoo.cfg</code> file (see below), or
+just specify ZookKeeper options directly in the
<code>${HBASE_HOME}/conf/hbase-site.xml</code>
+(If new to ZooKeeper, go the path of specifying your configuration in HBase's
hbase-site.xml).
+Every ZooKeeper configuration option has a corresponding property in the HBase
hbase-site.xml
+XML configuration file named <code>hbase.zookeeper.property.OPTION</code>.
+For example, the <code>clientPort</code> setting in ZooKeeper can be changed by
+setting the <code>hbase.zookeeper.property.clientPort</code> property.
+For the full list of available properties, see ZooKeeper's
<code>zoo.cfg</code>.
+For the default values used by HBase, see
<code>${HBASE_HOME}/conf/hbase-default.xml</code>.</p>
+
+<p>At minimum, you should set the list of servers that you want ZooKeeper to
run
+on using the <code>hbase.zookeeper.quorum</code> property.
+This property defaults to <code>localhost</code> which is not suitable for a
+fully distributed HBase (it binds to the local machine only and remote clients
+will not be able to connect).
+It is recommended to run a ZooKeeper quorum of 3, 5 or 7 machines, and give
each
+ZooKeeper server around 1GB of RAM, and if possible, its own dedicated disk.
+For very heavily loaded clusters, run ZooKeeper servers on separate machines
from the
+Region Servers (DataNodes and TaskTrackers).</p>
+
+<p>To point HBase at an existing ZooKeeper cluster, add
+a suitably configured <code>zoo.cfg</code> to the <code>CLASSPATH</code>.
HBase will see this file and use it to figure out where ZooKeeper is.
-Additionally set <code>HBASE_MANAGES_ZK</code> in <code>
${HBASE_HOME}/conf/hbase-env.sh</code>
- to <code>false</code> so that HBase doesn't mess with your ZooKeeper setup:
+Additionally set <code>HBASE_MANAGES_ZK</code> in
<code>${HBASE_HOME}/conf/hbase-env.sh</code>
+to <code>false</code> so that HBase doesn't mess with your ZooKeeper setup:</p>
<pre>
...
# Tell HBase whether it should manage it's own instance of Zookeeper or not.
export HBASE_MANAGES_ZK=false
</pre>
-For more information about setting up a ZooKeeper cluster on your own, see
-the ZooKeeper <a
href="http://hadoop.apache.org/zookeeper/docs/current/zookeeperStarted.html";>Getting
Started Guide</a>.
-HBase currently uses ZooKeeper version 3.2.0, so any cluster setup with a 3.x.x
-version of ZooKeeper should work.
-</p>
-<p>
-To have HBase manage the ZooKeeper cluster, you can use a <code>zoo.cfg</code>
- file as above, or edit the options directly in the
<code>${HBASE_HOME}/conf/hbase-site.xml</code>.
-Every option from the <code>zoo.cfg</code> has a corresponding property in the
-XML configuration file named <code>hbase.zookeeper.property.OPTION</code>.
-For example, the <code>clientPort</code> setting in ZooKeeper can be changed by
-setting the <code>hbase.zookeeper.property.clientPort</code> property.
-For the full list of available properties, see ZooKeeper's
<code>zoo.cfg</code>.
-For the default values used by HBase, see
<code>${HBASE_HOME}/conf/hbase-default.xml</code>.
-</p>
-<p>
-At minimum, you should set the list of servers that you want ZooKeeper to run
-on using the <code>hbase.zookeeper.quorum</code> property.
-This property defaults to <code>localhost</code> which is not suitable for a
-fully distributed HBase.
-It is recommended to run a ZooKeeper quorum of 5 or 7 machines, and give each
-server around 1GB to ensure that they don't swap.
-It is also recommended to run the ZooKeeper servers on separate machines from
-the Region Servers with their own disks.
-If this is not easily doable for you, choose 5 of your region servers to run
the
-ZooKeeper servers on.
-</p>
-<p>
-As an example, to have HBase manage a ZooKeeper quorum on nodes
-rs{1,2,3,4,5}.example.com, bound to port 2222 (the default is 2181), use:
+
+<p>As an example, to have HBase manage a ZooKeeper quorum on nodes
+<em>rs{1,2,3,4,5}.example.com</em>, bound to port 2222 (the default is 2181),
use:</p>
+<blockquote>
<pre>
${HBASE_HOME}/conf/hbase-env.sh:
@@ -273,77 +280,93 @@
...
</configuration>
</pre>
-</p>
-<p>
-When HBase manages ZooKeeper, it will start/stop the ZooKeeper servers as a
part
+</blockquote>
+
+<p>When HBase manages ZooKeeper, it will start/stop the ZooKeeper servers as a
part
of the regular start/stop scripts. If you would like to run it yourself, you
can
-do:
-<pre>
- ${HBASE_HOME}/bin/hbase-daemons.sh {start,stop} zookeeper
-</pre>
-Note that you can use HBase in this manner to spin up a ZooKeeper cluster,
+do:</p>
+<blockquote>
+<pre>${HBASE_HOME}/bin/hbase-daemons.sh {start,stop} zookeeper</pre>
+</blockquote>
+
+<p>Note that you can use HBase in this manner to spin up a ZooKeeper cluster,
unrelated to HBase. Just make sure to set <code>HBASE_MANAGES_ZK</code> to
<code>false</code> if you want it to stay up so that when HBase shuts down it
-doesn't take ZooKeeper with it.
-</p>
+doesn't take ZooKeeper with it.</p>
-<p>Of note, if you have made <i>HDFS client configuration</i> on your hadoop
cluster, HBase will not
-see this configuration unless you do one of the following:
+<p>For more information about setting up a ZooKeeper cluster on your own, see
+the ZooKeeper <a
href="http://hadoop.apache.org/zookeeper/docs/current/zookeeperStarted.html";>Getting
Started Guide</a>.
+HBase currently uses ZooKeeper version 3.2.0, so any cluster setup with a
3.x.x version of ZooKeeper should work.</p>
+
+<p>Of note, if you have made <em>HDFS client configuration</em> on your Hadoop
cluster, HBase will not
+see this configuration unless you do one of the following:</p>
<ul>
- <li>Add a pointer to your <code>HADOOP_CONF_DIR</code> to
<code>CLASSPATH</code> in <code>hbase-env.sh</code></li>
- <li>Add a copy of <code>hdfs-site.xml</code> (or
<code>hadoop-site.xml</code>) to <code>${HBASE_HOME}/conf</code>, or</li>
- <li>If only a small set of HDFS client configurations, add them to
<code>hbase-site.xml</code></li>
+ <li>Add a pointer to your <code>HADOOP_CONF_DIR</code> to
<code>CLASSPATH</code> in <code>hbase-env.sh</code>.</li>
+ <li>Add a copy of <code>hdfs-site.xml</code> (or
<code>hadoop-site.xml</code>) to <code>${HBASE_HOME}/conf</code>, or</li>
+ <li>if only a small set of HDFS client configurations, add them to
<code>hbase-site.xml</code>.</li>
</ul>
-An example of such an HDFS client configuration is
<code>dfs.replication</code>. If for example,
-you want to run with a replication factor of 5, hbase will create files with
the default of 3 unless
-you do the above to make the configuration available to HBase.
-</p>
+
+<p>An example of such an HDFS client configuration is
<code>dfs.replication</code>. If for example,
+you want to run with a replication factor of 5, hbase will create files with
the default of 3 unless
+you do the above to make the configuration available to HBase.</p>
<h2><a name="runandconfirm">Running and Confirming Your Installation</a></h2>
-<p>If you are running in standalone, non-distributed mode, HBase by default
uses
-the local filesystem.</p>
+<p>If you are running in standalone, non-distributed mode, HBase by default
uses the local filesystem.</p>
<p>If you are running a distributed cluster you will need to start the Hadoop
DFS daemons and
-ZooKeeper Quorum
-before starting HBase and stop the daemons after HBase has shut down.</p>
-<p>Start and
-stop the Hadoop DFS daemons by running
<code>${HADOOP_HOME}/bin/start-dfs.sh</code>.
+ZooKeeper Quorum before starting HBase and stop the daemons after HBase has
shut down.</p>
+
+<p>Start and stop the Hadoop DFS daemons by running
<code>${HADOOP_HOME}/bin/start-dfs.sh</code>.
You can ensure it started properly by testing the put and get of files into
the Hadoop filesystem.
HBase does not normally use the mapreduce daemons. These do not need to be
started.</p>
<p>Start up your ZooKeeper cluster.</p>
-<p>Start HBase with the following command:
-</p>
-<pre>
-${HBASE_HOME}/bin/start-hbase.sh
-</pre>
-<p>
-Once HBase has started, enter <code>${HBASE_HOME}/bin/hbase shell</code> to
obtain a
-shell against HBase from which you can execute commands.
-Test your installation by creating, viewing, and dropping
-To stop HBase, exit the HBase shell and enter:
-</p>
-<pre>
-${HBASE_HOME}/bin/stop-hbase.sh
+<p>Start HBase with the following command:</p>
+<blockquote>
+<pre>${HBASE_HOME}/bin/start-hbase.sh</pre>
+</blockquote>
+
+<p>Once HBase has started, enter <code>${HBASE_HOME}/bin/hbase shell</code> to
obtain a
+shell against HBase from which you can execute commands.
+Type 'help' at the shells' prompt to get a list of commands.
+Test your running install by creating tables, inserting content, viewing
content, and then dropping your tables.
+For example:
+<blockquote>
+<pre>hbase> # Type "help" to see shell help screen
+hbase> help
+hbase> # To create a table named "mylittletable" with a column family of
"mylittlecolumnfamily", type
+hbase> create "mylittletable", "mylittlecolumnfamily"
+hbase> # To see the schema for you just created "mylittletable" table and
its single "mylittlecolumnfamily", type
+hbase> describe "mylittletable"
+hbase> # To add a row whose id is "x", to the column
"mylittlecolumnfamily:x" with a value of 'x', do
+hbase> put "mylittletable", "x"
+hbase> # To get the cell just added, do
+hbase> get "mylittletable", "x"
+hbase> # To scan you new table, do
+hbase> scan "mylittletable"
</pre>
-<p>
-If you are running a distributed operation, be sure to wait until HBase has
shut down completely
-before stopping the Hadoop daemons.
-</p>
-<p>
-The default location for logs is <code>${HBASE_HOME}/logs</code>.
-</p>
-<p>HBase also puts up a UI listing vital attributes. By default its deployed
on the master host
-at port 60010 (HBase regionservers listen on port 60020 by default and put up
an informational
+</blockquote>
+
+To stop HBase, exit the HBase shell and enter:</p>
+<blockquote>
+<pre>${HBASE_HOME}/bin/stop-hbase.sh</pre>
+</blockquote>
+
+<p>If you are running a distributed operation, be sure to wait until HBase has
shut down completely
+before stopping the Hadoop daemons.</p>
+
+<p>The default location for logs is <code>${HBASE_HOME}/logs</code>.</p>
+
+<p>HBase also puts up a UI listing vital attributes. By default its deployed
on the master host
+at port 60010 (HBase RegionServers listen on port 60020 by default and put up
an informational
http server at 60030).</p>
<h2><a name="upgrading" >Upgrading</a></h2>
<p>After installing a new HBase on top of data written by a previous HBase
version, before
starting your cluster, run the <code>${HBASE_DIR}/bin/hbase migrate</code>
migration script.
It will make any adjustments to the filesystem data under
<code>hbase.rootdir</code> necessary to run
-the HBase version. It does not change your install unless you explicitly ask
it to.
-</p>
+the HBase version. It does not change your install unless you explicitly ask
it to.</p>
<h2><a name="client_example">Example API Usage</a></h2>
For sample Java code, see <a
href="org/apache/hadoop/hbase/client/package-summary.html#package_description">org.apache.hadoop.hbase.client</a>
documentation.
