138 lines
9.0 KiB
HTML
138 lines
9.0 KiB
HTML
|
<?xml version="1.0" encoding="UTF-8"?>
|
||
|
|
<!DOCTYPE html
|
||
|
|
PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
|
||
|
|
<html lang="en-us" xml:lang="en-us">
|
||
|
|
<head>
|
||
|
|
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
|
||
|
|
<meta name="security" content="public" />
|
||
|
|
<meta name="Robots" content="index,follow" />
|
||
|
|
<meta http-equiv="PICS-Label" content='(PICS-1.1 "http://www.icra.org/ratingsv02.html" l gen true r (cz 1 lz 1 nz 1 oz 1 vz 1) "http://www.rsac.org/ratingsv01.html" l gen true r (n 0 s 0 v 0 l 0) "http://www.classify.org/safesurf/" l gen true r (SS~~000 1))' />
|
||
|
|
<meta name="DC.Type" content="concept" />
|
||
|
|
<meta name="DC.Title" content="How journal management works" />
|
||
|
|
<meta name="abstract" content="Use journal management to create an object called a journal. Use a journal to define which objects you want to protect. You can have more than one journal on your system. A journal can define protection for more than one object." />
|
||
|
|
<meta name="description" content="Use journal management to create an object called a journal. Use a journal to define which objects you want to protect. You can have more than one journal on your system. A journal can define protection for more than one object." />
|
||
|
|
<meta name="DC.Relation" scheme="URI" content="rzakiconcepts.htm" />
|
||
|
|
<meta name="DC.Relation" scheme="URI" content="rzakijrnentry.htm" />
|
||
|
|
<meta name="DC.Relation" scheme="URI" content="../cl/crtjrn.htm" />
|
||
|
|
<meta name="DC.Relation" scheme="URI" content="../cl/chgjrn.htm" />
|
||
|
|
<meta name="DC.Relation" scheme="URI" content="../cl/wrkjrna.htm" />
|
||
|
|
<meta name="DC.Relation" scheme="URI" content="rzakiremotekickoff.htm" />
|
||
|
|
<meta name="copyright" content="(C) Copyright IBM Corporation 2004, 2006" />
|
||
|
|
<meta name="DC.Rights.Owner" content="(C) Copyright IBM Corporation 2004, 2006" />
|
||
|
|
<meta name="DC.Format" content="XHTML" />
|
||
|
|
<meta name="DC.Identifier" content="rzakihowwrks" />
|
||
|
|
<meta name="DC.Language" content="en-us" />
|
||
|
|
<!-- All rights reserved. Licensed Materials Property of IBM -->
|
||
|
|
<!-- US Government Users Restricted Rights -->
|
||
|
|
<!-- Use, duplication or disclosure restricted by -->
|
||
|
|
<!-- GSA ADP Schedule Contract with IBM Corp. -->
|
||
|
|
<link rel="stylesheet" type="text/css" href="./ibmdita.css" />
|
||
|
|
<link rel="stylesheet" type="text/css" href="./ic.css" />
|
||
|
|
<title>How journal management works</title>
|
||
|
|
</head>
|
||
|
|
<body id="rzakihowwrks"><a name="rzakihowwrks"><!-- --></a>
|
||
|
|
<!-- Java sync-link --><script language="Javascript" src="../rzahg/synch.js" type="text/javascript"></script>
|
||
|
|
<h1 class="topictitle1">How journal management works</h1>
|
||
|
|
<div><p>Use journal management to create an object called a <span class="uicontrol">journal</span>.
|
||
|
|
Use a journal to define which objects you want to protect. You can have more
|
||
|
|
than one journal on your system. A journal can define protection for more
|
||
|
|
than one object.</p>
|
||
|
|
<p>You can journal the objects that are listed below:</p>
|
||
|
|
<ul><li>Database physical files</li>
|
||
|
|
<li>Access paths</li>
|
||
|
|
<li>Data areas</li>
|
||
|
|
<li>Data queues</li>
|
||
|
|
<li>Integrated file system objects (stream files, directories, and symbolic
|
||
|
|
links).</li>
|
||
|
|
</ul>
|
||
|
|
<div class="section"><h4 class="sectiontitle">Journal entries</h4><p>The system keeps a record of changes
|
||
|
|
you make to objects that are journaled and of other events that occur on the
|
||
|
|
system. These records are called journal entries. You can also write journal
|
||
|
|
entries for events that you want to record, or for objects other than the
|
||
|
|
object that you want to protect with journaling.</p>
|
||
|
|
<p>For example, some journal
|
||
|
|
entries identify activity for a specific database record such as add, update,
|
||
|
|
or delete. (If the updated object image after the update is the same as the
|
||
|
|
image before the update, then journal entries are not deposited for that update.)
|
||
|
|
Also journal entries identify activity such as a save, open, or close operation
|
||
|
|
for an object. Journal entries can also identify other events that occur,
|
||
|
|
such as security-relevant events on the system or changes made by dynamic
|
||
|
|
performance tuning. The Journal entry information link below describes
|
||
|
|
all the possible journal entry types and their contents.</p>
|
||
|
|
<p>Each journal
|
||
|
|
entry can include additional control information that identifies the source
|
||
|
|
of the activity, including the user, job, program, time, and date. The entries
|
||
|
|
that the system deposits for a journaled object reflect the changes made to
|
||
|
|
that journaled object. For example, the entries for changes to database records
|
||
|
|
can include the entire image of the database record, not just the changed
|
||
|
|
information.</p>
|
||
|
|
</div>
|
||
|
|
<div class="section"><h4 class="sectiontitle">Journal receivers</h4><p>The system writes entries to an
|
||
|
|
object called a <span class="uicontrol">journal receiver</span>. The system sends
|
||
|
|
entries for all the objects associated with a particular journal to the same
|
||
|
|
journal receiver.</p>
|
||
|
|
<p>You can attach journal receivers to a journal by using iSeries™ Navigator
|
||
|
|
or the Create Journal (CRTJRN) and Change Journal (CHGJRN) commands. The system
|
||
|
|
adds journal entries to the attached receiver. Journal receivers that are
|
||
|
|
no longer attached to a journal and are still known to the system are <span class="uicontrol">associated</span> with
|
||
|
|
that journal. Use the Work with Journal Attributes (WRKJRNA) command to see
|
||
|
|
a list of receivers associated with a journal.</p>
|
||
|
|
<p>The system adds an entry
|
||
|
|
to the attached journal receiver when an event occurs to a journaled object.
|
||
|
|
The system numbers each entry sequentially. For example, it adds an entry
|
||
|
|
when you change a record in a journaled database file member. Journal entries
|
||
|
|
contain information that identifies:</p>
|
||
|
|
<ul><li>Type of change</li>
|
||
|
|
<li>Record that has been changed</li>
|
||
|
|
<li>Change that has been made to the record</li>
|
||
|
|
<li>Information about the change (such as the job being run and the time of
|
||
|
|
the change)</li>
|
||
|
|
</ul>
|
||
|
|
<p>When you are journaling objects, changes to the objects are added
|
||
|
|
to the journal receiver. The system does not journal data that you retrieved
|
||
|
|
but did not change. If the logical file record format of a database file does
|
||
|
|
not contain all the fields that are in the dependent physical file record
|
||
|
|
format, the journal entry still contains all the fields of the physical file
|
||
|
|
record format. In addition, if you are journaling access paths, entries for
|
||
|
|
those access paths are added to the journal. If the updated physical file
|
||
|
|
image after the update is the same as the image before the update, and if
|
||
|
|
the file has no variable length fields, then journal entries are not deposited
|
||
|
|
for that update. If the updated data area image after the update is the same
|
||
|
|
as the image before the update, then journal entries are not deposited for
|
||
|
|
that update. If the attribute that was requested to be changed was already
|
||
|
|
that value, then journal entries are not deposited for that change.</p>
|
||
|
|
</div>
|
||
|
|
<div class="section"><h4 class="sectiontitle">Summary of the journaling process</h4><p>The following
|
||
|
|
figure shows a summary of journal processing. Objects A and B are journaled;
|
||
|
|
object C is not. Programs PGMX and PGMY use object B. When you make a change
|
||
|
|
to object A or B, the following occurs:</p>
|
||
|
|
<ul><li>The change is added to the attached journal receiver.</li>
|
||
|
|
<li>The journal receiver is written to auxiliary storage.</li>
|
||
|
|
<li>The changes are written to the main storage copy of the object.</li>
|
||
|
|
</ul>
|
||
|
|
<p>Object C changes are written directly to the main storage copy of
|
||
|
|
the object because it is not being journaled. Only the entries added to the
|
||
|
|
journal receiver are written immediately to auxiliary storage. Changes against
|
||
|
|
the object may stay in main storage until the object is closed.</p>
|
||
|
|
<br /><img src="rzaki502.gif" alt="Illustration showing journaling overview" /><br /><p>You can also take advantage of the remote journal function. The
|
||
|
|
remote journal function allows you to associate a journal on a remote system
|
||
|
|
with a journal on a local system. Journal entries on the local system are
|
||
|
|
replicated to the remote journal receiver.</p>
|
||
|
|
</div>
|
||
|
|
</div>
|
||
|
|
<div>
|
||
|
|
<div class="familylinks">
|
||
|
|
<div class="parentlink"><strong>Parent topic:</strong> <a href="rzakiconcepts.htm" title="This topic explains how journal management works, why to use it, and how it affects your system.">Journal management concepts</a></div>
|
||
|
|
</div>
|
||
|
|
<div class="relconcepts"><strong>Related concepts</strong><br />
|
||
|
|
<div><a href="rzakijrnentry.htm" title="This topic provides information and tasks for working with journal entries.">Journal entry information</a></div>
|
||
|
|
<div><a href="rzakiremotekickoff.htm" title="Use remote journal management to establish journals and journal receivers on a remote system that are associated with specific journals and journal receivers on a local system. Remote journal management replicates journal entries from the local system to the journals and journal receivers that are located on the remote system after they have been established.">Remote journal management</a></div>
|
||
|
|
</div>
|
||
|
|
<div class="relref"><strong>Related reference</strong><br />
|
||
|
|
<div><a href="../cl/crtjrn.htm">Create Journal (CRTJRN) command</a></div>
|
||
|
|
<div><a href="../cl/chgjrn.htm">Change Journal (CHGJRN) command</a></div>
|
||
|
|
<div><a href="../cl/wrkjrna.htm">Work with Journal Attributes (WRKJRNA) command</a></div>
|
||
|
|
</div>
|
||
|
|
</div>
|
||
|
|
</body>
|
||
|
|
</html>
|