HBASE-4530 expanding backup section

git-svn-id: https://svn.apache.org/repos/asf/hbase/trunk@1178437 13f79535-47bb-0310-9956-ffa450edef68
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Doug Meil 2011-10-03 16:07:10 +00:00
parent fbe50d0404
commit f0aeae2ba4
1 changed files with 59 additions and 3 deletions

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@ -89,13 +89,26 @@
--peer.adr=server1,server2,server3:2181:/hbase TestTable</programlisting>
</para>
</section>
<section xml:id="export">
<title>Export</title>
<para>Export is a utility that will dump the contents of table to HDFS in a sequence file. Invoke via:
<programlisting>$ bin/hbase org.apache.hadoop.hbase.mapreduce.Export &lt;tablename&gt; &lt;outputdir&gt; [&lt;versions&gt; [&lt;starttime&gt; [&lt;endtime&gt;]]]
</programlisting>
</para>
</section>
<section xml:id="import">
<title>Import</title>
<para>Import is a utility that will load data that has been exported back into HBase. Invoke via:
<programlisting>$ bin/hbase org.apache.hadoop.hbase.mapreduce.Import &lt;tablename&gt; &lt;inputdir&gt;
</programlisting>
</para>
</section>
<section xml:id="rowcounter">
<title>RowCounter</title>
<para>RowCounter is a utility that will count all the rows of a table. This is a good utility to use
as a sanity check to ensure that HBase can read all the blocks of a table if there are any concerns of metadata inconsistency.
<programlisting>$ bin/hbase org.apache.hadoop.hbase.mapreduce.RowCounter
<programlisting>$ bin/hbase org.apache.hadoop.hbase.mapreduce.RowCounter &lt;tablename&gt; [&lt;column1&gt; &lt;column2&gt;...]
</programlisting>
</para>
</section>
@ -240,8 +253,51 @@ false
</section>
<section xml:id="ops.backup">
<title >HBase Backup</title>
<para>See <link xlink:href="http://blog.sematext.com/2011/03/11/hbase-backup-options/">HBase Backup Options</link> over on the Sematext Blog.
<para>There are two broad strategies for performing HBase backups: backing up with a full cluster shutdown, and backing up on a live cluster.
Each approach has pros and cons.
</para>
<para>For additional information, see <link xlink:href="http://blog.sematext.com/2011/03/11/hbase-backup-options/">HBase Backup Options</link> over on the Sematext Blog.
</para>
<section xml:id="ops.backup.fullshutdown"><title>Full Shutdown Backup</title>
<para>Some environments can tolerate a periodic full shutdown of their HBase cluster, for example if it is being used a back-end analytic capacity
and not serving front-end web-pages. The benefits are that the NameNode/Master are RegionServers are down, so there is no chance of missing
any in-flight changes to either StoreFiles or metadata. The obvious con is that the cluster is down. The steps include:
</para>
<section xml:id="ops.backup.fullshutdown.stop"><title>Stop HBase</title>
<para>
</para>
</section>
<section xml:id="ops.backup.fullshutdown.nn"><title>Backup NameNode</title>
<para>
</para>
</section>
<section xml:id="ops.backup.fullshutdown.distcp"><title>Distcp</title>
<para>Distcp could be used to either copy the contents of the hbase directory in HDFS to either the same cluster, or do a different cluster.
</para>
<para>Note: Distcp works in this situation because the cluster is down and there are no in-flight edits to files.
This is not recommended on a live cluster.
</para>
</section>
</section>
<section xml:id="ops.backup.live.replication"><title>Live Cluster Backup - Replication</title>
<para>This approach assumes that there is a second cluster.
See the HBase page on <link xlink:href="http://hbase.apache.org/replication.html">replication</link> for more information.
</para>
</section>
<section xml:id="ops.backup.live.copytable"><title>Live Cluster Backup - CopyTable</title>
<para>The <xref linkend="copytable" /> utility could either be used to copy data from one table to another on the
same cluster, or to copy data to another table on another cluster.
</para>
<para>Since the cluster is up, there is a risk that edits could be missed in the copy process.
</para>
</section>
<section xml:id="ops.backup.live.export"><title>Live Cluster Backup - Export</title>
<para>The <xref linkend="export" /> approach dumps the content of a table to HDFS on the same cluster. To restore the data, the
<xref linkend="import" /> utility would be used.
</para>
<para>Since the cluster is up, there is a risk that edits could be missed in the export process.
</para>
</section>
</section>
</chapter>