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In SAP-side customized tia Viewer Core configuration, the mapping to an instance resides on SAP-side. For more information read about column Viewer Conf in https://kgs-software.atlassian.net/wiki/spaces/WIKI/pages/3257106464/SAP+Customizing+Vc#%2FKGS1%2FVIEWER_CUST-Transaction .
In Content Server Viewer (CSV) configuration, the mapping is specified in the tia Viewer configuration using parameter
tia.repositoryinstancemapping, see also https://kgs-software.atlassian.net/wiki/x/B4C1wg.
tia Viewer Core maps the repository repositories to instance default, if no explicit mapping exists.
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