103 lines
7.7 KiB
HTML
103 lines
7.7 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="reference" />
|
|
<meta name="DC.Title" content="iSeries source and target restrictions and considerations for DDM" />
|
|
<meta name="abstract" content="When the source server is an iSeries server, iSeries database functions can be used on remote files. There are some restrictions, however." />
|
|
<meta name="description" content="When the source server is an iSeries server, iSeries database functions can be used on remote files. There are some restrictions, however." />
|
|
<meta name="DC.subject" content="system, server, iSeries, source, restrictions, accessing, target restrictions, target, considerations, join logical files, join logical file, logical file, join logical files, WAITFILE (maximum file wait time) parameter, performance considerations, WAITFILE parameter, target DDM (TDDM), DDM target considerations, source DDM (SDDM), SDDM (source DDM), DDM source considerations, target DDM (TDDM), System/38, DDM target considerations, DDM architecture, member not supported, command, CLRPFM (Clear Physical File Member), Clear Physical File Member (CLRPFM), command, CL, Clear Physical File Member (CLRPFM), physical file member, clearing" />
|
|
<meta name="keywords" content="system, server, iSeries, source, restrictions, accessing, target restrictions, target, considerations, join logical files, join logical file, logical file, join logical files, WAITFILE (maximum file wait time) parameter, performance considerations, WAITFILE parameter, target DDM (TDDM), DDM target considerations, source DDM (SDDM), SDDM (source DDM), DDM source considerations, target DDM (TDDM), System/38, DDM target considerations, DDM architecture, member not supported, command, CLRPFM (Clear Physical File Member), Clear Physical File Member (CLRPFM), command, CL, Clear Physical File Member (CLRPFM), physical file member, clearing" />
|
|
<meta name="DC.Relation" scheme="URI" content="rbae5compile.htm" />
|
|
<meta name="DC.Relation" scheme="URI" content="../books/sc415406.pdf" />
|
|
<meta name="copyright" content="(C) Copyright IBM Corporation 1999, 2006" />
|
|
<meta name="DC.Rights.Owner" content="(C) Copyright IBM Corporation 1999, 2006" />
|
|
<meta name="DC.Format" content="XHTML" />
|
|
<meta name="DC.Identifier" content="rbae5targetres" />
|
|
<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>iSeries source and target
|
|
restrictions and considerations for DDM</title>
|
|
</head>
|
|
<body id="rbae5targetres"><a name="rbae5targetres"><!-- --></a>
|
|
<!-- Java sync-link --><script language="Javascript" src="../rzahg/synch.js" type="text/javascript"></script>
|
|
<h1 class="topictitle1"><span class="keyword">iSeries</span> source and target
|
|
restrictions and considerations for DDM</h1>
|
|
<div><p>When the <em>source</em> server is an <span class="keyword">iSeries™ server</span>, <span class="keyword">iSeries</span> database functions can be used
|
|
on remote files. There are some restrictions, however.</p>
|
|
<div class="section"><p>The restrictions are:</p>
|
|
<ul><li>A source <span class="keyword">iSeries server</span> can create
|
|
files on a <span class="keyword">System/38™</span>, but the
|
|
DDM architecture file models are used. As a result, no multiformat logical
|
|
or join logical files can be created on a non-<span class="keyword">iSeries</span> target
|
|
server, including a <span class="keyword">System/38</span>.</li>
|
|
<li>Save or restore operations do not save or restore the data on a target
|
|
server; only the DDM file object can be saved or restored locally.</li>
|
|
<li>Operations that delay for a time period (that is, that wait for a file
|
|
or record) are determined by the time values specified on the target server.
|
|
(These values are specified by the WAITFILE and WAITRCD parameters on various
|
|
CL commands.) This can result in increased delay times when DDM is used to
|
|
access files or records remotely.</li>
|
|
<li>Query requests (OPNQRYF) to a <span class="keyword">System/38</span> cannot
|
|
use group selection and join processing.</li>
|
|
<li>When running <span class="keyword">System/36™</span> applications
|
|
to or from an <span class="keyword">iSeries server</span>, these
|
|
applications might result in time-outs while waiting for a resource to become
|
|
available. When running <span class="keyword">System/36</span> applications
|
|
to or from another <span class="keyword">System/36</span>,
|
|
the application waits indefinitely for the resource to become available. <p>For
|
|
both source and target DDM jobs, due to the way DDM sends APPC operations,
|
|
it is possible for the DDM job on the secondary side of the APPC conversation
|
|
to wait indefinitely after a line failure or other failures at the remote
|
|
server.</p>
|
|
<div class="p">Consider the following suggestions to avoid indefinite waits:
|
|
<ul><li>If the remote server supports record lock time-outs, ensure reasonable
|
|
time values are specified. For example, on a target <span class="keyword">iSeries server</span> or <span class="keyword">System/38</span> database file, do not use maximum
|
|
values for CRTPF ... WAITRCD. <p>WAITRCD addresses read-for-update operations,
|
|
but does not apply to other file operations, such as read only, add, and so
|
|
on.</p>
|
|
</li>
|
|
<li>When using an SDLC secondary line, use a time value for the line inactivity
|
|
timer (INACTTMR). Do <em>not</em> use the *NOMAX value. </li>
|
|
<li>Provide the person responsible for server operation with the associated
|
|
line, controller, and device names (or a list of DDM jobs that might run).
|
|
If a DDM job then appears to be waiting indefinitely, this person can
|
|
display the job information to determine if the job is waiting indefinitely
|
|
by reviewing the job's processing unit time use (by using the <span class="cmdname">Display
|
|
Job (DSPJOB)</span> command to display the active run attributes).</li>
|
|
</ul>
|
|
</div>
|
|
</li>
|
|
</ul>
|
|
</div>
|
|
<div class="section"><p>When the <em>target</em> server is an <span class="keyword">iSeries server</span>, <span class="keyword">iSeries</span> database functions can be used
|
|
to access remote files, with the following restrictions:</p>
|
|
<ul><li>The physical files that the logical files or join logical files are based
|
|
on must exist on the same <span class="keyword">iSeries server</span>. </li>
|
|
<li>A logical file on a source <span class="keyword">iSeries server</span> cannot
|
|
share the access path of a remote file (on any target server).</li>
|
|
<li>Query requests (OPNQRYF), which require group selection and join processing
|
|
from a <span class="keyword">System/38</span>, do not work.</li>
|
|
</ul>
|
|
</div>
|
|
</div>
|
|
<div>
|
|
<div class="familylinks">
|
|
<div class="parentlink"><strong>Parent topic:</strong> <a href="rbae5compile.htm" title="Remote files can be accessed by iSeries application programs written in the HLL and control language.">Program modification requirements for DDM</a></div>
|
|
</div>
|
|
<div class="relconcepts"><strong>Related concepts</strong><br />
|
|
<div><a href="../books/sc415406.pdf" target="_blank">Communications Management PDF</a></div>
|
|
</div>
|
|
</div>
|
|
</body>
|
|
</html> |