je/docs/ReplicationGuide/backups.html

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<p>
Because JE replication causes a current copy of your
environment to be available at every data node in the group, the need
for frequent backups is greatly reduced. Basically, every time a
change is made on the Master, that change is backed up to every
Replica node currently running. The result is that for each write
operation you get a real-time incremental backup to
<span class="emphasis"><em>n-1</em></span> nodes, where <span class="emphasis"><em>n</em></span> are
the total number of data nodes (including the Master) currently
running in your replication group.
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<p>
For this reason, JE does not currently support formal
incremental backups of replicated environments. An application
based upon the <a class="ulink" href="../java/com/sleepycat/je/util/DbBackup.html" target="_top">DbBackup</a> utility class can be written to allow
administrators to create full backups. This is useful for
creating a backup to be stored on offline media, if your data
strategy calls for that level of protection.
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<p>
Remember that when performing a full backup, you should obtain
the backup from a node that is current. Either use the Master
node itself, or use a Replica node that must acknowledge a
transaction commit before the commit operation can complete on
the Master.
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<p>
Note that <a class="ulink" href="../java/com/sleepycat/je/util/DbBackup.html" target="_top">DbBackup</a> has some functionality that
is specifically useful for replicated environments. See
<a class="xref" href="dbbackup.html" title="Backing up a Replicated Application">Backing up a Replicated Application</a>
for details.
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