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<ManualTopic ID="/baanerp/da/onlinemanual/000005" xml:lang="en">
	<Header>
		<Title xmlns:HTML="http://www.w3.org/TR/REC-html40">Introduction to multisite control</Title>
		<Keyword ContextSensitive="No"><Level1>Exchange multisite control</Level1>
		</Keyword>
	</Header>
	<GeneralSection><Paragraph class="Default">This module is used to control the exchange of data between multiple sites.</Paragraph>
		<List><ListIntro>You can, for example:</ListIntro>
			<ListItem>At one site: run the export and the import in virtually one process, and the latter can be run based on the results of the first.</ListItem>
			<ListItem>At multiple sites: run the export at the source system, move or copy the resulting <Link href="/baanerp/da/glossary/glossary#000001" role="glossary">ASCII files</Link> to the target system and then run the import there.</ListItem>
		</List>
		<Figure space-and-orientation="indented-estimated"><HTML:IMG height="249" width="465" SRC="../images/tr_graph_000005.gif" path="/enterpriseserver/add-ons/da/onlinemanual" btb-count="1" btb-count2="1" btb-image-name="tr_graph_000005.gif" btb-source-path="C:\SVN\docnl\Technology\EnterpriseServer~8.5\EnterpriseServer" btb-image-path="/enterpriseserver/add-ons/da/images/tr_graph_000005.gif" ID="IDAM0V5B" alt="[...]" xmlns:HTML="http://www.w3.org/TR/REC-html40"/></Figure>
		<Paragraph class="Default">The export <Link href="/baanerp/da/glossary/glossary#000002" role="glossary">batch</Link> and an import batch are linked. The <Link href="/baanerp/da/glossary/glossary#000031" role="glossary">exchange link</Link> links the batches from the source and target site at batch level. The link is set up according to the local autonomy model. This means that each site controls its own <Link href="/baanerp/da/glossary/glossary#000016" role="glossary">export procedure</Link> and <Link href="/baanerp/da/glossary/glossary#000015" role="glossary">import procedure</Link>. There is no master or slave.</Paragraph>
		<Paragraph class="Default">The exchange links are stored at the target and point to the export batch at the source site. If an exchange link is defined, a subscription is stored at the source site, which points to the import batch at the target site. The link is active when both the exchange link at the target site and the subscription at the source site are available.</Paragraph>
		<Paragraph class="Default">During a <Link href="/baanerp/da/glossary/glossary#000004" role="glossary">regular</Link> export, the <GUIRef href="/baanerp/da/xch" role="module">Exchange</GUIRef> module checks for subscriptions. In this case, a message is sent to the target site that defines which files are exported and where they are stored. The target site stores that information when the message is received. the <GUIRef href="/baanerp/da/xch" role="module">Exchange</GUIRef> module checks the received information from the source sites during a regular import to see if there is any data waiting to be imported. If this is the case, the files are copied from the source site to the target site and then they are imported. Finally the target reports to the source that the data has been imported.</Paragraph>
		<Note><SectionTitle>
                                 Note
                              </SectionTitle>
			<Paragraph class="Default">The figure only shows one exporting batch and one importing batch, but you can also define multiple targets per source or multiple sources per target.</Paragraph>
		</Note>
		<List><ListIntro>To be able to use <Link href="/baanerp/da/glossary/glossary#000043" role="glossary">multisite control</Link> it is important that:</ListIntro>
			<ListItem>remote users are available for both systems (refer also to the <GUIRef href="/baanerp/tt/aad/ttaad0550m000" role="session">Systems (ttaad0550m000)</GUIRef> and <GUIRef href="/baanerp/tt/aad/ttaad2501m000" role="session">Remote User Data (ttaad2501m000)</GUIRef> sessions).</ListItem>
			<ListItem>the <GUIRef href="/baanerp/da/xch/daxch4200m000" role="session">Receive Remote Procedure Calls (daxch4200m000)</GUIRef> session is running on both systems.</ListItem>
		</List>
	</GeneralSection>
	<Note><SectionTitle>
                              Note
                           </SectionTitle>
		<Paragraph class="Default">For details on the procedure to set up a multisite control exchange, refer to chapter 5, "Multisite Control" in the <DocRef>Exchange - User`s Guide (U8405 US)</DocRef>.</Paragraph>
	</Note>
	<RelatedTopics><SectionTitle>
                              Related topics
                           </SectionTitle>
		<RelTopic><Link href="/baanerp/da/onlinemanual/000017" role="manual">To use exchange links</Link>
		</RelTopic>
		<RelTopic><Link href="/baanerp/da/onlinemanual/000018" role="manual">Description of the subscription mechanism</Link>
		</RelTopic>
		<RelTopic><Link href="/baanerp/da/onlinemanual/000001" role="manual">Introduction to the Exchange module</Link>
		</RelTopic>
	</RelatedTopics>
</ManualTopic>
